lower fox river basin water quality trading economic feasibility … · 2019-10-29 · 1 lower fox...
TRANSCRIPT
1
Lower Fox River Basin Water Quality Trading
Economic Feasibility Assessment
Contact: Mark S. Kieser
Kieser & Associates, LLC 536 E. Michigan Ave., Suite 300
Kalamazoo, MI 49007 (269) 344-7117
January 16, 2015
Project Team:
i | P a g e
Table of Contents List of Tables ....................................................................................................................................... iii
Executive Summary ..................................................................................................................................... I
Credit Demand ....................................................................................................................................... I
Credit Supply ........................................................................................................................................ II
Comparison of Demand and Supply ....................................................................................................III
Economic Analysis ..............................................................................................................................III
I. ............................................................................................................................................................. Introduction 1
II. ............................................................................................................................................. Demand Assessment 3
Overview of Assessment Methods for WQT Demand ..........................................................................5
WWTF Demand Assessment .................................................................................................................5
WWTF Mass Reduction Determination ..........................................................................................6
WWTF Reduction Analysis Results ................................................................................................7
WWTF Cost of Reduction Assessment Methods ..........................................................................11
WWTF Cost of Reduction Results ................................................................................................11
MS4 Demand Assessment ...................................................................................................................14
MS4 Mass Reduction Determination .............................................................................................14
MS4 Cost of Reduction Assessment Methods ...............................................................................17
MS4 Demand Analysis Results .....................................................................................................18
III................................................................................................................................................ Supply Assessment 23
Ag and Rural Area Potential Credit Supply Overview ........................................................................23
Ag and Rural Potential Credit Supply Determination .........................................................................25
Overview of Methods to Assess TMDL Load Allocation Reductions from Rural Sources ..........25
Detailed Methods to Assess Cropland Loads ................................................................................27
Detailed Methods to Assess Animal Feeding Operation Loads ....................................................30
Detailed Methods to Assess Streambank and Riparian Gully Erosion Loads ...............................31
Universal Credit Threshold Analysis .............................................................................................32
Results of BMP Implementation Reductions on Croplands ..........................................................35
ii | P a g e
Results of BMP Implementation Reductions for Animal Feeding Operations .............................40
Results of BMP Implementation Reductions for Streambank and Riparian Gully BMPs ............40
TMDL Implementation Cost Estimates .........................................................................................43
Credit Supply Volume Calculation Considerations .......................................................................45
Trade Ratio Determination to Calculate Credits from Reductions ................................................45
Interim and Long-term Credit Results ...........................................................................................47
Credit Price Point Determination ...................................................................................................52
WWTF Credit Supply ..........................................................................................................................61
Considerations and Recommendations for Other Potential Credit Suppliers ......................................62
IV. ................................................................................................................. Comparison of Demand and Supply 64
Comparison of Demand and Supply Method.......................................................................................64
Review of Supply and Demand Methods ......................................................................................65
Credit Supply Volume and Demand Comparison .........................................................................65
V. ...................................................................................................................... Conclusions & Recommendations 73
Works Cited ...............................................................................................................................................77
Appendix A ................................................................................................................................................78
Wastewater Treatment Facility Cost Estimation Methods ..................................................................79
Appendix A Works Cited...........................................................................................................................80
Appendix B ................................................................................................................................................81
Appendix C ................................................................................................................................................90
iii | P a g e
List of Tables
Table E-1. Basinwide comparison of annual demand and supply. .............................................. III
Table E-2. Example 303(d) listed watersheds where TP credit supplies are limited compared to
MS4 demand. ................................................................................................................................ III
Table E-3. The LFWR willingness to pay price points for buyers, and credit price points for Ag
and rural generation of credits. ..................................................................................................... IV
Table II-1. WWTF names and WPDES permit numbers evaluated in the study. ......................... 7
Table II-2. WWTFs indicated to have a potential trading demand under maximum loading
conditions from 2008 to 2013. ........................................................................................................ 8
Table II-3a. Estimated reduction values for Industrial WWTFs not currently achieving the WI
DNR preliminary WQBELs. ........................................................................................................... 9
Table II-4. Estimated reduction values for WWTFs not currently achieving the WI DNR
preliminary WQBELs, potential ability to meet these through upgrades, and estimated upgrade
and O&M costs. ............................................................................................................................ 12
Table II-5. Evaluation of WWTF annualized unit costs to determine a range of probable credit
prices. ............................................................................................................................................ 14
Table II-6. Results from MS4 demand analysis. .......................................................................... 19
Table II-7. Total phosphorus demand and estimated cost for each MS4 to meet 2012 TMDL
WLA reduction goals. ................................................................................................................... 19
Table II-8. TSS demand and estimated cost totals for each MS4. ................................................ 20
Table II-9a. Capital, operation and maintenance costs for stormwater wet detention pond
facilities treating runoff from areas with 35 percent impervious surfaces. ................................... 21
Table II-10. Estimated low, medium and high annualized unit cost for TP and TSS for
stormwater reductions. .................................................................................................................. 22
Table III-1. Crop rotations selected by the Ag Oversight Committee for the credit supply
analysis. ......................................................................................................................................... 26
Table III-2. Cropland universal credit threshold and Animal Feeding Operation, streambank and
gully credit thresholds by TMDL subwatersheds. ........................................................................ 34
Table III-3. BMP system 3 list of individual BMPs applied for each crop rotation by year of
application. .................................................................................................................................... 36
Table III-4. Total phosphorus reduction estimates for croplands in each HUC-12 subwatershed.
....................................................................................................................................................... 37
Table III-5. Total suspended solids reduction estimates for each HUC-12 subwatershed. ......... 38
Table III-6. AFO, streambank and gully baseline and load allocation required reductions. ....... 41
Table III-7. Streambank and gully TSS baseline estimates and TMDL reduction requirements. 43
Table III-8. Total cost and annualized cost summaries for Ag BMP systems. ............................. 44
Table III-9. Cropland and AFO trade ratio development by subwatershed. ................................. 46
Table III-10. Streambank erosion trade ratio development by subwatershed. ............................. 47
Table III-11. Potential phosphorus credits generated by cropland BMPs (offsetting lbs TP/yr
discharged). ................................................................................................................................... 48
iv | P a g e
Table III-12. Potentially available interim and long-term TSS cropland credits (offsetting tons
TSS/yr discharged)........................................................................................................................ 50
Table III-13. High, medium and low credit price point ranges for Ag and rural phosphorus credit
generation capabilities. ................................................................................................................. 52
Table III-14. High, medium and low credit price point ranges for Ag and rural TSS credit
generation capabilities. ................................................................................................................. 52
Table III-15. Ag and rural interim TP credit supply by price ranges for 2 to 1 trade ratios. ....... 54
Table III-16. Ag and rural long-term TP credit supply by price ranges for 2 to 1 trade ratios. ... 56
Table III-17. Ag and rural interim TSS credit supply by price ranges for 2 to 1 trade ratios. ..... 58
Table III-18. Ag and rural long-term TSS credit supply by price ranges for 2 to 1 trade ratios. 60
Table IV-1. LFRW basinwide credit reduction requirements and Ag and rural credit supply
estimates. ....................................................................................................................................... 65
Table IV-2. Mud Creek and Ashwaubenon Creek MS4 buyer reduction requirements compared
to Ag and rural long-term credit generation potential. ................................................................. 66
Table IV-3. Economic cost comparisons of buyer willingness to pay and credit price points for
TP. ................................................................................................................................................. 71
I | P a g e
EXECUTIVE SUMMARY
This report assesses the economic feasibility of a Water Quality Trading (WQT) program for
total phosphorus (TP) and total suspended solids (TSS) in the Lower Fox River Watershed
(LFRW) of Wisconsin. The LFRW has had an approved Total Maximum Daily Load (TMDL)
since 2012. This Lower Fox River Basin Water Quality Trading Economic Feasibility
Assessment is one element of a larger “Fox P Trade Project” in response to this TMDL. The Fox
P Trade Project is being directed by the Great Lakes Commission (GLC) in cooperation with the
USDA Natural Resources Conservation Service (NRCS), and the Wisconsin Department of
Natural Resources (WI DNR). The analyses supporting this report were completed by a
consulting team of experts on water quality trading led by Kieser & Associates, LLC
(Kalamazoo, Michigan) and supported by XCG Consultants Ltd. (Oakville, Ontario) and
Troutman Sanders LLP (Washington D.C.)—the Project Team.
ES
Evaluating the economic feasibility of water quality trading in the LFRW involved three key
steps: 1) assessing demand for water quality credits; 2) assessing supply of credits that could be
generated by rural nonpoint sources; and 3) analysis of demand compared to supply to identify
key gaps and recommendations to advance trading.
FS
Findings of the analysis suggested the potential generation of 95,701 interim (5-year) and
5,019 long-term TP credits (lbs/yr), and 29,504 interim and 10,278 long-term TSS credits
(tons/yr) within the LFRW. Demand for these credits varied between wastewater
treatment facilities (WWTFs) and Municipal Separate Stormwater Systems (MS4s).
Estimates of annual TP credit demand for individual WWTFs that may seek to trade
ranged from 357 to 81,863 lbs of TP/yr while demand from all MS4s ranged from 369 to
5,968 lbs of TP/yr and 39 to 1,973 tons of TSS/yr.
GS
The overall potential for TP water quality trading appears low for WWTFs and MS4s due
to an inadequate supply of long-term phosphorus credits within the LFRW. TSS-based
trading by MS4s may be more favorable due to substantially higher costs associated with
municipal stormwater treatment compared to much lower TSS credit costs and a more
adequate supply stemming from rural nonpoint source controls.
Credit Demand
HS
The demand part of this assessment examined pollutant load reductions needed to achieve permit
compliance consistent with the 2012 Lower Fox River TMDL for 31 industrial and municipal
WWTFs and for 25 permitted MS4s.
IS
WWTF phosphorus credit demand was determined by examining the difference between current
discharge limits and likely future limits to meet load reduction requirements. As there were no
II | P a g e
TSS reduction requirements in the 2012 TMDL for WWTFs, the WWTF portion of the demand
analysis focused only on phosphorus. The ability to achieve anticipated TP limits with current
technology was a determining factor for assessing water quality trading credit demand. If a
WWTF could not likely achieve new limits with current treatment capacity, it was assumed that
the facility would pursue the minimum facility upgrade or operational changes that would meet
the WI DNR forecasted permit limits under the TMDL. In other words, the approach assumed
WWTFs would optimize their operations whenever possible over choosing to upgrade or
expand their facilities. Study results suggested that 10 of the 31 actively discharging
WWTFs in the LFRW would still need to implement some form of upgrade and would
therefore be potential buyers in a WQT market.
To determine MS4 demand, the differences between the published 2012 TMDL current day TP
and TSS loads and the targeted wasteload allocations were compared. MS4 demand was
substantial considering projected needs to meet TMDL allocations for TP and TSS.
JS
Credit Supply
KS
The 2012 TMDL provided only a single load allocation in each of the 20 HUC-12 subwatersheds
in the LFRW that encompassed all nonpoint sources including agriculture and other rural land
uses. The feasibility study ultimately segregated these nonpoint loads by predominant
sources including cropland, animal feeding operations (AFOs), and streambank and gully
erosion. Because not all agricultural land is used for the same purposes, variation in erosion
rates and load reduction from cropland was more extensively examined by crop rotation and
prevailing practices to better assess potential credit supply.
A GIS spatial analysis process was used to assess cropland load reduction potential based
on seven representative crop rotations on predominant soil types. Similarly, a GIS spatial
analysis was used to estimate load reductions for AFOs as well as streambank and riparian gully
erosion.
Rural nonpoint source credit availability and distribution within the basin was determined for a
total of 40 smaller drainage areas within the 20 HUC-12 basins. This was necessary to
accommodate the WI DNR “point of water quality standards application" approach which
specifies that water quality credits must be generated in the same drainage area of the
impaired stream and/or river segment. For WWTFs interested in buying credits, this
expanded the eligible credit generating watersheds without creating additional “downstream”
discount factors to generate credits. For MS4s, this application either expanded eligible
watershed acreage for credit generation, or reduced such coverage depending on their location in
the LFRW. This was due in part to MS4s having numerous stormwater outfalls with some
located in small subwatersheds with impairments.
III | P a g e
Comparison of Demand and Supply
When credit demand was compared to supply (Table E.S.-1), overall opportunities for
WWTFs to trade for TP were found to largely exist only for an interim 5-year window of
agricultural credit availability. Long-term TP credit supply was quite limited compared to
demand. TP supply was similarly limited for MS4s. TSS-based trading appeared to be the
most robust trading opportunity in the basin corresponding to MS4 demand and available
supply. The study also identified that credit availability was particularly limited in select
subwatersheds.
Table 0.S.-0-1. Lower Fox River Watershed potential credit buyer’s current day discharge loading reduction
requirements and potential credit suppliers estimated generation capacity.
Buyer TP Reduction Demand (lbs TP) TSS Reduction (tons TSS)
All Identified WWTFs 144,399 --
Ten Facilities Identified with
Short-term Reduction
Potential Demand
68,656
--
MS4s 32,805 10,960
Credit
Supplier
Potential For
Interim TP
Credits
Potential for
Long-term TP
Credits
Potential For
Interim TSS
Credits
Potential For
Long-term TSS
Credits
Cropland 84,306 1,996 12,555 4,265
Streambank & Gully 5,519 1,599 16,949 6,013
AFO 5,876 1,424 -- --
Subtotals 95,701 5,019 29,504 10,278
Individual farms will likely be able to generate interim credits for a WQT program, and in
some circumstances, long-term credits, but installation of farm-based conservation
practices alone is not likely to achieve TMDL load reductions for agriculture across all
subwatersheds in the LFRW. Emerging technologies (e.g., manure digesters) or export of
excess manure out of the watershed, though not considered in this analysis, may be necessary to
achieve TMDL load reduction targets across the entire watershed.
Economic Analysis
Overall economic feasibility of WQT in the LFRW was assessed by comparing costs of
traditional WWTF treatment upgrades and representative urban Best Management Practice
(BMP) applications for MS4s with the costs of rural nonpoint source reductions. Low, medium,
and high estimated costs for WWTP treatment upgrades to meet anticipated TP limits
were estimated at $42, $91 and $400, respectively per pound of TP reduction.
IV | P a g e
For MS4s, assuming costs for wet detention ponds to achieve TP and TSS load reduction
requirements, estimated costs per pound of phosphorus ranged from $880 to $3,400, and
from $3,400 to $13,520 per ton of TSS. It would expected that actual costs of TMDL
implementation, and the associated desire to purchase water quality credits, would vary
among individual MS4s based on their unique hydrogeomorphic, financial, and land use
circumstances.
Cost analysis for rural nonpoint source load reductions consisted of selecting a system of Best
Management Practices (BMPs) to fully address TMDL reduction needs and then, based on
NRCS practice standards and payment schedules, developing an annual life-cycle cost analysis.
Extensive crop rotations applied in the LFRW basin yielded more extensive BMP costs than
other rural practices allowing for computation of a credit cost range of low, medium and high for
cropland credits. TP credit prices (which take into account a trading ratio of >2 to 1 applied
to calculated TP and TSS load reductions) yielded a range from $26 for gully erosion
corrections up to $7,900 for AFO controls. For TSS credits, prices ranged from $14 for
gully erosion up to $1,560 for select crop management practices.
Table E.S.-1 provides comparisons of willingness to pay price ranges for WWTFs and MS4s
with rural nonpoint source credit costs for both TP and TSS. Willingness to pay credit prices for
WWTFs assumed that trading would need to provide at least a 25% cost-savings over the actual
upgrade costs noted above. This 25% assumption was not applied to MS4 reductions since these
were often substantially higher than nonpoint source credits such that cost-saving margins were
not in play as with WWTFs.
Table 0.S.-2. Annualized unit costs ($/credit) for credit buyers and estimated credit costs for supply sources in the Lower
Fox River Watershed.
Buyer TP Reduction Demand (lbs TP) TSS Reduction (tons TSS)
All Identified WWTFs 144,399 --
Ten Facilities Identified with
Short-term Reduction
Potential Demand
68,656
--
MS4s 32,805 10,960
Credit
Supplier
Potential For
Interim TP
Credits
Potential for
Long-term TP
Credits
Potential For
Interim TSS
Credits
Potential For
Long-term TSS
Credits
Cropland 84,306 1,996 12,555 4,265
Streambank & Gully 5,519 1,599 16,949 6,013
AFO 5,876 1,424 -- --
Subtotals 95,701 5,019 29,504 10,278
Table E.S.-2 illustrates that WQT was considerably more cost-effective for WWTFs and
MS4s at higher levels of willingness to pay price points for buyers. WWTFs facing
V | P a g e
compliance costs in the $91-$400 credit range for TP would likely find WQT an attractive
compliance option, even at the higher end of this price range. The case for water quality
trading was stronger for MS4s which have a higher estimated willingness to pay compared
to much lower credit costs for both TP and TSS. Rural credit sources, excluding AFOs, were
able to generate cost-effective credits in most circumstances. The high cost of AFO credits
(which consider existing requirements for load reductions that in turn, eliminate credits)
suggested that this source was a poor candidate for WQT, even though it might be very
beneficial for pollutant load reductions that can otherwise help achieve water quality goals.
Overall results of the WQT economic feasibility analysis for the LFRW suggested
reasonable potential for trading between WWTFs, MS4s and rural nonpoint sources. The
analysis identified strong potential for TSS-based trading by MS4s as reduction
requirement compliance schedules draw near for communities under the 2012 TMDL. The
potential for TP trading that would benefit municipal and industrial WWTFs and MS4
communities was identified, though likely at a more limited scale than TSS trading. TP
credits were identified as cost-effective for an interim 5-year timeframe at even at medium
and high price points for WWTF upgrades. However, the ability for rural nonpoint
sources to generate sufficient long-term TP credits to fulfill future WWTF and MS4
demand was a deeply constraining factor. Eligible credit generating areas will also be a key
factor for any buyer potentially seeking to trade in select areas that have severe limitations
depending on location in the LFRW.
Findings in this study can be used to frame trading program needs and define broader
considerations in the LFRW. As all trading is fundamentally driven by site-specific
conditions, this report should be used as guide for future trading opportunities, not as the
definitive final analysis for any potential buyer or seller contemplating trading in LFRW.
1 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
I. INTRODUCTION
An assessment of the economic feasibility of water quality trading (WQT) in the Lower Fox
River Watershed (LFRW) of Wisconsin was completed by a Project Team led by Kieser &
Associates, LLC (K&A) (Kalamazoo, Michigan) that included XCG Consultants Ltd. (XCG)
(Oakville, Ontario) and Troutman Sanders LLP (Washington, D.C.). The feasibility study was
one element of a larger “Fox P Trade Project” directed by the Great Lakes Commission (GLC)
and a Project Management Team (PMT). The PMT was comprised of interested stakeholders
including the USDA Natural Resource Conservation Service (NRCS) and the Wisconsin
Department of Natural Resources (Wisconsin DNR). This report documents the Project Team’s
analyses, findings and conclusions of the feasibility study for the GLC and PMT.
The GLC and multiple stakeholders have envisioned a WQT program in the LFRW that will
assist with cost-effectively reducing total phosphorus (TP) and total suspended solids (TSS)
loading to address associated water quality impairments. The program could incorporate both
point sources and nonpoint sources that contribute to loading in the watershed. Point sources
included in the feasibility evaluation were both municipal and industrial wastewater treatment
facilities (WWTFs) and permitted municipal separate storm sewer systems (MS4s). Nonpoint
sources considered in the evaluation were runoff from cropland and animal feeding operations
(AFOs), as well as streambank and riparian gully erosion.
To determine the economic feasibility of trading in the LFRW, the Project Team estimated the
potential credit demand and supply for TP and TSS in the watershed. The assessment focused on
the amount of WWTF reductions needed to satisfy future permit compliance needs for TP along
with the cost of traditional end-of-pipe treatment compared to available supply and costs of
nonpoint source credits available at the HUC-12 watershed scale. For MS4s, demand and
associated costs were estimated for both TP and TSS and then also compared to the nonpoint
source credit supply.
An essential part of this assessment was to determine eligible credit sources by subwatersheds.
This determination incorporated several considerations which form the basis for all credit
demand and supply considerations applied herein. The first eligibility consideration was from
the Wisconsin DNR. If the trade was for a listed water quality parameter(s), eligible WQT
subwatersheds required delineation to identify available credits for dischargers within impaired
segments above the point of standards application. This is based on Section 2.10.1 of the
Wisconsin Water Quality Trading Guidance (Wisconsin DNR, 2013a) which states:
“Trades may occur both upstream and downstream of the generator’s discharge
point provided that the potential for localized water quality standard exceedances
is adequately addressed. The ultimate extent of the area available for trading is
limited to the drainage area contributing to the impaired segment.”
2 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
With an impaired segment approach, many WWTFs and MS4s credit buyers would have a
“built-in” downstream trade potential with no trade ratio penalty for downstream sellers as long
as those sellers also discharge into the same impaired stream segment. In addition, buyers
discharging directly into Green Bay could purchase credits from within the entire watershed of
Duck Creek and other tributaries that drain to the bay, as well as upstream on the Lower Fox
mainstem with no downstream trade ratio penalty.
Based on these directives and interpretation of Wisconsin DNR trading guidance for this
feasibility assessment, the following eligibility conditions were applied for this analysis:
A spatial analysis sub-divided the 20 HUC-12 watersheds in the LFRW into smaller sub-
HUC-12 subwatersheds based on the impaired waters point of standards application.
These subdivisions resulted in 40 sub-HUC-12 subwatersheds.
Buyers discharging into an impaired reach must purchase credits from the contributing
area to the point of standards application used in the 303(d) listing process.
For point sources discharging directly into Green Bay, the entire LFRW is considered a
credit-source eligible area because the bay itself is impaired and considered an end point
of an impaired water body.
Purchasing credits from downstream sources located in a different HUC-12 subwatershed
was not considered.
The results of the economic assessment of WQT in the LFRW based on these considerations are
presented in the following sections of this report:
Demand Assessment (for both WWTFs and MS4s)
Supply Assessment (for agriculture, WWTFs and other potential opportunities)
Comparison of Demand and Supply
Conclusions and Recommendations
Each section for the demand and supply assessments includes an overview of various
considerations used, a description of the analysis, methods used and results.
3 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
II. DEMAND ASSESSMENT
Calculating the potential demand for WQT credits in the LFRW depended on the anticipated
reduction requirements faced by permitted dischargers and the location of facilities seeking
credits. Potential credit demand for WWTFs and MS4s was derived from the approved 2012
Total Maximum Daily Load and Watershed Management Plan for Total Phosphorus and Total
Suspended Solids in the Lower Fox River Basin and Green Bay study (Wisconsin DNR, 2012).
This “2012 TMDL” also assigned substantial reductions for other anthropogenic sources of TP
and TSS loading within the watershed (for example, agriculture—see Supply Assessment
section).
For the WWTF demand assessment, demand was determined by the difference between current
discharge limits and likely future limits to meet TMDL load reduction requirements for TP.
Wisconsin DNR supplied the Project Team with potential water quality based effluent limits
(WQBELs) as well as Discharge Monitoring Report (DMR) summaries from 2008 to 2013 in
these regards. In addition, Wisconsin DNR permit fact sheets (when available) served as the
primary basis for assessing current treatment technologies being used in the basin from which
future treatment upgrades would be needed to address potential WQBELs. These upgrades were
used in turn, to assess potential WWTF compliance costs.
The difference between current estimated loads in the 2012 TMDL and corresponding targeted
load reduction goals for TP and TSS were used for determining MS4 credit demand. Existing
local and regional implementation data and costs for wet detention ponds were used as the sole
means to achieve targeted load reductions. This approach was chosen in the absence of local
data on other stormwater treatment options.
At the direction of the Wisconsin DNR, the WQT demand analyses for WWTFs and MS4s were
based on the current treatment capability and historic loadings without assessing full build-out
conditions in the basin. This adjustment to the project scope was made due to the limited amount
of growth and the actual industrial closings that occurred during the last five to ten years. In
addition, this approach assumed WWTFs would choose to optimize their current operations over
choosing to upgrade or expand their facilities. Optimization provides a greater opportunity for
residual demand for load reductions that could be met with water quality trading whereas major
upgrades or facility expansions would likely eliminate the need for water quality trading. A
complete “future” analysis would also need to identify a future condition for each TP and TSS
contributor. For example, it is not possible to predict an industrial WWTF’s future market
viability in the context of current and recent industrial trends in the basin. This type of
assessment is thus complicated by the need to forecast many different market conditions to
estimate future production goals. Such was not possible in the limited scope and budget of this
assessment.
4 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Of the 2012 TMDL listed and new industrial and municipal WWTFs in the 20 HUC-12
subwatersheds of the LFRW, 20 industrial and 13 municipal facilities were initially considered in
this evaluation. These facilities are shown in Figure II-1. For the 20 LFRW HUC-12s, these
were further subdivided into a total of 40 sub-HUC-12 catchments to recognize impaired waters
and corresponding impacts on demand and supply for these WWTFs.
Figure II-1. New and existing industrial and municipal WWTFs in the 20 HUC-12 watersheds of the LFRW reflecting
potential status with future TMDL compliance, the need for upgrades and WQT potential.
Permitted MS4s examined in this analysis are required to achieve phosphorus reductions of 30
percent, except for the MS4s discharging to Garners Creek (63.1 percent) and Mud Creek (39
percent) per the 2012 TMDL. In addition, MS4s are required to provide TSS reductions that
range from 28.5 to 65.2 percent of current loads.
5 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Overview of Assessment Methods for WQT Demand
The first step in the WQT demand analysis was to gather available information from the
Wisconsin DNR regarding current loading conditions for potential credit buyers (WWTF and
MS4s1) as well as treatment capabilities and costs (where available). Information collected was
used to assess potential credit demand by comparing current loading to the reduction
requirements described in the 2012 TMDL for permitted dischargers. Where information was
not directly available for dischargers, treatment costs for the required reductions were estimated.
Unit costs for TP and TSS treatment were then used to assess whether the permitted entities
might seek to purchase WQT credits in order to partially or fully meet new compliance
requirements based on cost savings with trading. For WWTFs, comparable costs would be for
upgrading treatment capabilities for TP, while for MS4s these would be for installing wet
detention basins to treat TP and TSS.
XCG led the Project Team assessment of potential demand by estimating the current effluent
concentration requirements and associated phosphorus loading reductions for WWTFs based on
preliminary WQBEL mass limits provided by WI DNR. Maximum potential credit demand for
WWTFs was estimated by applying WQBEL effluent mass limits provided by WI DNR, and
then calculating estimated maximum phosphorus load reductions that might possibly result in a
credit purchase (Wisconsin DNR, 2013a) (Wisconsin DNR, 2013b) (Wisconsin DNR, 2013c).
Methods used to establish MS4 credit demand were based on deriving a per-acre unit loading
applied for TP and TSS based on the 2012 TMDL. To estimate the baseline loading for the 40
subwatersheds, the analysis applied the unit load to incorporated municipal footprints (where
these were readily available for GIS mapping). When incorporated footprints were not readily
available, estimates were derived from the 2012 TMDL waste load allocation and MS4 acreage
information.
WWTF Demand Assessment
The potential demand from WWTFs was estimated by assessing whether the facility would
likely need to upgrade its treatment technology in order to meet the 2012 TMDL load
requirement for TP along with the expected upgrade cost. No potential demand for TSS was
considered as the 2012 TMDL did not require TSS reductions for WWTFs. This evaluation
considered the size of the facility, current technology, and level of future reduction required. If
additional technology was deemed necessary, the Project Team estimated the expected cost of
implementing the upgrade.
1 It should be noted that Wisconsin passed a new rule allowing up to a 20-year variance from the phosphorus rule for
entities that can satisfactorily demonstrate the rule causes severe economic hardship (2013 WISCONSIN ACT 378;
enacted April 23, 2014). The method for application of this rule will be determined by WI DNR and US EPA.
6 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
In order to conduct this analysis, specific information was requested from WI DNR and other
entities in the watershed. Information received regarding existing WWTF operations from the
Wisconsin DNR included:
Existing level of treatment
Current permit capacity (MGD)
Historic facility data (2008-2013)
Mass limit averaging period
WQBEL monthly average TP mass effluent limit
WQBEL 6-month average TP mass effluent limit
In addition to the WI DNR data request, WWTF information also was collected by: conducting
an online survey via SurveyMonkeyTM
; holding a webinar to seek input from facility
representatives; and hosting an in-person meeting to facilitate discussions with facility
representatives.
WWTF Mass Reduction Determination
Data collection methods provided only limited facility-specific data and consequently, general
assumptions were made regarding facility optimization, upgrades and associated costs. The
Discharge Monitoring Report summaries from 2008 to 2013 were evaluated to estimate the
maximum amount of potential phosphorus reductions required for WWTFs. The potential
maximum loading reduction requirements for a facility were estimated by selecting the
maximum average annual discharge from any of the years and combining that with the maximum
average annual concentration from any of the years. This approach provides a potential highest
case credit demand scenario by using the two maximums even from different years.
These summary data were then compared to the preliminary monthly and/or 6-month average
effluent WQBELs for TP provided by WI DNR. An indicator of potential trading demand was
considered to exist where the annual loading based on WQBEL daily values was lower than the
calculated maximum potential effluent TP loading. The 2012 TMDL wasteload allocations are
calculated assuming full utilization of the hydraulic design capacity. Therefore, it can be the
case where current flow at a WWTF allows for higher concentrations of TP until there is an
increase is flow.
For facilities with an indication of potential trading demand, target effluent concentrations and
capital costs were estimated for achieving those limits where sufficient data were provided.
Compliance concentration estimates were based on the 2008 to 2013 average discharge flow
summaries. These effluent loading projections at historic flows were then compared to the
historic treatment performance to determine if any additional reduction in effluent TP would be
required.
7 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
If reductions were likely, the facility’s existing level of treatment was reviewed and any
additional work required for the plant to meet the effluent TP limits was assessed. It was
assumed that secondary treatment facilities could achieve effluent TP concentrations of 0.3 mg/L
through chemical addition and optimization. In addition, it was assumed that a facility could
achieve effluent TP concentrations of 0.1 mg/L through tertiary granular filtration. Membrane
ultrafiltration was assumed to be a reasonable Limit of Technology for phosphorus removal and
could reliably achieve an effluent TP of 0.07 mg/L on an annual basis.
Currently the lowest effluent TP limit issued by WI DNR is 0.075 mg/L. It was assumed that
effluent TP of less than 0.07 mg/L cannot be achieved through upgrades alone. If a facility’s
level of treatment appeared to be sufficient to meet the target effluent TP limit, then an
Optimization Study was recommended. These are considered general guidelines and thus, the
capabilities of each facility might differ based on the age of equipment, plant configuration,
wastewater characteristics, and other factors. The costs estimates generated by this method were
one half to one fifth the cost estimates for full upgrades as indicated by WI DNR staff2.
WWTF Reduction Analysis Results
The 31 actively discharging WWTFs located in the LFRW reviewed in this analysis are
presented in Table II-1.
Table II-1. Industrial and municipal WWTFs and associated WPDES permit numbers evaluated in the study.
Industrial Municipal
Facility Name
WPDES
Permit Facility Name
WPDES
Permit
Exopack - Menasha 0026999 Appleton 0023221
Appleton Coated - Combined Locks 0000990 De Pere - GBMSD 0023787
Georgia Pacific Consumer Products LP 0001848
Grand Chute - Menasha
West 0024686
Georgia Pacific Consumer Products LP - Day St. 0001261 Green Bay MSD 0020991
Cellu Tissue - Neenah 0000680 Heart of the Valley 0031232
Kimberly Clark - NP/BG 0037842
Town of Holland SD #1
001 0028207
Procter & Gamble 0001031 Neenah - Menasha 0026085
Thilmany LLC - Kaukauna 0000825 Wrightstown 0022497
2 Person communication with J. Baumann, December 1, 2014
8 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
SCA Tissue North America 0037389 Wrightstown SD#1 0022438
Belgioioso Cheese - Sherwood 0027201 Forest Junction 0032123
Schroeder's Greenhouse 0046248 Wrightstown SD#2 0022357
Galloway Company 0027553 Sherwood 0031127
Fox Energy LLC 0061891 Freedom SD #1 0020842
Menasha Electric & Water 101 0027707
Wisconsin Public Service - Pulliam 101 0000965
Arla Foods LLC- Holland 0027197
Green Bay Packaging 0000973
Provimi Foods - Seymour 0026999
Table II-2 identifies the industrial and municipal WWTFs of those in Table II-1 that may likely
need to consider trading and/or upgrades using the maximum loading indicator for potential
demand. The values listed in Table II-2 illustrate sizeable demand when considering year-to-
year variability in both flows and concentrations. The maximum loading indicator was not used
in later analyses in this report due to a WI DNR request to focus on existing flows as described
above. However, the information presented in Table II-2 was considered relevant in the event
these WWTF entities should face growth pressures in the near future.
Table II-2. WWTFs indicated to have potential trading demand under maximum loading conditions from 2008 to 2013.
Industrial Municipal
Facility Name
Maximum Potential
Reduction Demand*
(lbs TP/yr) Facility Name
Maximum Potential
Reduction Demand*
(lbs TP/yr)
Appleton Coated -
Combined Locks 7,145 Appleton 17,202
Georgia Pacific
Consumer Products LP 10,969 De Pere - GBMSD 679
Cellu Tissue - Neenah 330
Grand Chute - Menasha
West 7,240
Kimberly Clark - NP/BG 428 Green Bay MSD 38,639
Procter & Gamble 932 Heart of the Valley 1968
9 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Thilmany LLC -
Kaukauna 21,928
Town of Holland SD #1
001 21
SCA Tissue North
America 001/007 7,219 Neenah - Menasha 13,629
Belgioioso Cheese -
Sherwood 1,216 Wrightstown 167
Wisconsin Public
Service - Pulliam 101 212 Wrightstown SD#1 585
Provimi Foods -
Seymour 40 Forest Junction 176
Wrightstown SD#2 5
Freedom SD #1 285
*Note maximum flow and maximum concentrations used to determine this value may have occurred in different
years.
Tables II-3a and II-3b identify the Industrial and Municipal WWTF concentration goals and
target reductions for 14 facilities that will need to likely meet the WI DNR preliminary WQBEL
mass limit applications with treatment upgrades.
Table II-3a. Estimated reduction values for Industrial WWTFs not currently achieving the WI DNR preliminary
WQBELs.
INDUSTRIES
Facility
Applied
6-month
Average
WQBEL
and/or
Monthly
WQBEL
WQBEL Based
Concentration
Equivalent at
Historic Flows
(mg/L TP)
Reduction
Percent
Potentially
Achievable
Through
Optimization
Alone?
Reduction
Needed
(lbs TP/yr)
Appleton
Coated -
Combined
Locks
Monthly
0.28 38% No 2,870
Georgia
Pacific
Consumer
Products LP
Monthly/6-
Month 0.23 12% No 1,053
Procter & Monthly/6-0.02 54% No 357
10 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Gamble Month
Thilmany LLC
- Kaukauna Monthly 0.24 52% No 14,896
SCA Tissue
North America
001/007
Monthly 0.26 38% No 2,887
Belgioioso
Cheese–
Sherwood
Monthly 0.39 66% Yes 357
Table II-3b. Estimated reduction values for Municipal WWTFs not currently achieving the WI DNR preliminary
WQBELs.
MUNICIPALITIES
Facility
Applied
6-month
Average
WQBEL
and/or
Monthly
WQBEL
WQBEL
Based
Concentration
Equivalent at
Historic Flows
(mg/L TP)
Reduction
Percent
Potentially
Achievable
Through
Optimization
Alone?
Reduction
Needed
(lbs. TP/yr)
Appleton Monthly/6-
Month 0.23 63% No 14,282
Grand Chute -
Menasha West
Monthly/6-
Month 0.18 54% No 4,161
Green Bay
MSD
Monthly/6-
Month 0.22 49% No 18,863
Heart of the
Valley
Monthly/6-
Month 0.25 18% No 869
Neenah -
Menasha
Monthly/6-
Month 0.22 54% No 8,416
Wrightstown Monthly/6-
Month 0.43 12% Yes 37
Wrightstown
SD#1 Monthly 1.42 47% Yes 240
Forest
Junction
Monthly/6-
Month 2.33 36% Yes 79
11 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
WWTF Cost of Reduction Assessment Methods
A total cost evaluation was completed for those WWTFs required to reduce phosphorus loading
to comply with the permit requirement. The incremental capital costs developed for the addition
of granular media filters were based on comparison of the facility’s existing flows and actual
costs for upgrades to other facilities over a range of flows. The results of these analyses were
organized into tables and maps
according to the point of standards
application for 303(d) listed waters
and the 2012 TMDL. (These tables
and maps are presented in the
Comparison of Demand and Supply
section of this document.)
An allowance of 40 percent was
included in these estimates (see inset
for explanation). The costs for
Optimization Studies were based on
the complexity of the existing
treatment system, size of the facility,
and experience conducting
Optimization Studies. These did not
include any additional assessments or
field studies recommended through
the Optimization Study. The costs to
upgrade a secondary treatment facility to a tertiary facility with granular media filtration were
based on a typical per capita flow of 455 L/cap/d (120 Gal/cap/d), Harmon Peak Factor, and the
costs developed for the Review of Phosphorus Removal at Municipal Sewage Treatment Plants
Discharging to the Lake Simcoe Watershed (XCG, 2010). Further details of the methods used in
this particular assessment are provided in Appendix A.
WWTF Cost of Reduction Results
The capital and O&M cost estimates based on the methods described above were calculated for
the 14 facilities requiring further reductions at current loading to comply with the preliminary
WQBELs for TP (from Tables II-3a and b). Four of these facilities were determined to likely be
able to comply with reduction requirements by completing an Optimization Study and
implementing related findings. Table II-4 therefore presents the potential WWTF costs
associated with the WQBEL current condition assessment.
Incremental capital costs developed for the addition
of granular media filters were based on comparison
of the facility’s existing flows and actual costs for
upgrades to other facilities over a range of flows,
and included allowances only for the following:
Filter mechanism and media
Filter building construction/expansion
Process piping modifications
Yard piping
Electrical/SCADA modifications and
upgrades
An allowance of 40 percent was included to cover
costs associated with engineering, mobilization,
demobilization, contractor overhead, and other
miscellaneous construction costs.
12 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table II-4. Estimated capital and O&M costs, or optimization study costs for WWTFs not currently achieving the WI
DNR preliminary WQBELs.
Facility
Reduction
Needed
(lbs TP/yr)
Estimated Upgrade
Cost (Millions)
Additional
Estimated O&M
(Thousands)
Industries
Appleton Coated -
Combined Locks 2,870 $3.40 $18
Georgia Pacific
Consumer Products LP 1,053 $5.46 $28
Procter & Gamble* 357
Thilmany LLC -
Kaukauna 14,896 $8.25 $42
SCA Tissue North
America 001/007 2,887 $2.16 $13
Belgioioso Cheese -
Sherwood 357 $50K Optimization Study
Municipalities
Appleton 14,282 $5.94 $30
Grand Chute -
Menasha West 4,161 $3.74 $20
Green Bay MSD 18,863 $11.75 $61
Heart of the Valley 869 $3.25 $17
Neenah - Menasha 8,416 $5.45 $27
Wrightstown 37 $50K Optimization Study
Wrightstown SD#1 240 $25K Optimization Study
Forest Junction 79 $25K Optimization Study
*Proctor & Gamble was determined to not be able to comply using this type of upgrade alone.
Using the information in Table II-4, a range (i.e., low, medium and high pricing) of annualized
upgrade unit costs expressed as $/lb TP were developed as the first step to illustrate a probable
WWTF willingness to pay scenario for nonpoint source credits via trading. The annualized costs
computed for WWTFs is the life-cycle cost (LCC) method recommended by the US Department
of Energy, NIST Handbook 135 (1995). This method is required by the Federal life-cycle
13 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
requirements in the Code of Federal Regulations, 10 CFR 436, Subpart A[1] for Federal energy
and water conservation projects. The LCC method provides the total cost of owning, operating,
maintaining and replacing the system over the life of the project. All costs are discounted to
reflect the time-value of money. The Department of Energy (DOE) publication for inflation
factors and nominal discount factors is used. The base date for the year 2014 was selected to
reflect both the latest published DOE values (June 2013) and agricultural project payment
schedules used in the supply analysis.
In order to compare WWTF upgrade costs with agricultural treatment measures a similar project
life must be established for each source. The project life of a WWTF upgrade was considered to
be 20 years. For agricultural and rural projects, the cost is based on the 2014 NRCS
Environmental Quality Incentive Program (EQIP) payment schedules. A rural nonpoint source
conservation project can have a 1, 10, 15 or 20-year project life. These project lives can be
extended to match the WWTF upgrade expected life. Therefore, the project life period selected
for comparing agricultural projects with WWTF upgrades was 20 years. The annualized values
are based on current dollar method which applies a 3.30% inflation rate and a nominal discount
rate of 6.0 percent. The nominal discount factor is inclusive of inflation and allows the decision-
maker to compare costs that occur in different years by taking into account the time-value of
money. The decision-maker can then be indifferent to cash amounts entered at different points in
time. For instance, using a 5 percent discount rate, a $100 dollar investment today reflects a $78
sum five years from now due to the time-value of money. In this way, projects with expenses
occurring in different years can be compared.
For WWTFs, annualized upgrade costs were based on annualized capital and O&M costs with
the life of the upgrade assumed to be 20 years. Next, from the list of facilities potentially facing
upgrades, the annualized unit costs were determined by dividing the annual cost by the number
of TP pounds required to be removed. From this working list, three unit treatment costs were
selected and used to create a unit cost range of low, medium and high. (The annualized cost for
upgrades can be high and still generate a low upgrade unit cost when the amount of TP that is
treated by the upgrade is substantial.) Finally, the unit cost estimate for upgrades are reduced 25
percent to recognize that credit buyers will likely want to pay less for credits than for upgrades
due to uncertainties and the novelty of water quality trading. Table II-5 presents phosphorus unit
price points and willingness to pay price points. These values are used in the Comparison of
Demand and Supply section of this report for a discussion of potential trading opportunities.
14 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table II-5. Evaluation of WWTF annualized unit costs to determine a range of probable credit prices.
Unit Cost
Range
Unit Cost for
Upgrade
($/lb TP)
Trading Credit
Purchase Price
(assuming 25%
below unit cost)
Annualized Cost
Applied for
Upgrades1
Low $42 $32 $630,000
Medium $91 $68 $261,000
High $400 $300 $418,000
1 Annualized life-cycle cost methods based on current dollar analysis using a 20-year life of project, 3.30 percent
inflation rate and a 6 percent nominal discount factor
MS4 Demand Assessment
Potential TP and TSS credit demand from MS4s was estimated by assessing the need for
additional stormwater treatment and related costs to meet 2012 TMDL load reduction goals.
This evaluation considered the size of the MS4 footprint, current stormwater best management
practices (BMPs) and level of necessary future reductions. If additional BMPs were deemed
necessary, the Project Team estimated the expected cost based on implementing wet detention
basins. Although communities are expected to use a variety of BMPs, wet detention ponds are
considered to be useful surrogates in this study. Wet detention basins are familiar to most
communities and are typically cost-effective. Where space is available, they can be integrated
into existing systems to provide multiple benefits (e.g., nutrient and sediment removal, hydraulic
buffering).
In order to conduct this analysis, local regional stormwater implementation information was
requested from WI DNR and other entities in the watershed. In addition, the Project Team
gathered additional information by hosting an in-person meeting to facilitate discussions with
MS4 representatives. Such information and feedback was quite limited and therefore, certain
assumptions were made for the analysis as outlined in the following section.
MS4 Mass Reduction Determination
U.S. EPA’s Final Water Quality Trading Policy (EPA, 2003) states that trading must be
consistent with Clean Water Act provisions and applicable water quality standards. To satisfy
this policy, WI DNR guidance for an MS4 discharging into an impaired waterbody restricts
credit generation to locations within the same subwatershed area. This area is defined by the
water quality point of standards application and its upstream contributing areas so the total
pollutant load to the receiving water is not increased. Because an individual MS4 often spans
more than one HUC-12 watershed, and a HUC-12 often has more than one impaired waterbody,
15 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
it was therefore necessary to delineate the HUC-12 watersheds into smaller subwatersheds based
on the impaired waterbody. To accomplish this, the following steps were taken:
1) HUC-12 watershed boundaries, stream lines, and water bodies were extracted from
the U.S. Geological Survey (USGS) National Hydrography Dataset (NHD) high
resolution geo-database
2) The 2014 Wisconsin DNR 303(d) impaired stream segments coverage was obtained
from the Wisconsin DNR website
3) All spatial layers were overlain together, and the HUC-12 watersheds were delineated
into smaller sub-watersheds for each of the impaired stream segments in the LFRW
by: a) drawing a line around existing upstream tributaries and waterbodies, b)
connecting this to the upper end of the impaired stream segment, and c) crossing the
existing HUC-12 boundaries at a right angle
A total of 40 sub-HUC-12 watersheds resulted from this delineation process. These
subwatersheds provided the geographic basis for the MS4 demand analysis and are presented in
Figure II-2.
To estimate potential credit demand, it was assumed that MS4 boundaries coincided with the city
limits/boundaries. The U.S. Census Places (city boundaries) coverage from the 2014
Topologically Integrated Geographic Encoding and Referencing (TIGER) map products was
used to delineate these special limits. However, six cities and all towns were missing from this
coverage. Two methods were used to determine the boundaries and areas for these missing
MS4s including:
1) Urban area coverage (urban areas and clusters containing at least 2,500 people) from the
TIGER dataset was used after areas of known cities were extracted and omitted; the
resulting coverage was then compared to the positions of the cities and towns shown on
Google Maps and distributed to these cities and towns
2) Corporate limits for the towns of Neenah, Menasha and Greenville, as well as the city of
Grand Chute, were manually digitized based on the Census roads coverage and zoning
maps obtained from the cities’ websites
The MS4 areas then were distributed into the sub-HUC-12 watersheds.
Following the GIS processing and analysis, some differences remained between the 2012 TMDL
subwatersheds and the sub-HUC 12s in select areas. For Lawrence, there was no GIS coverage
of the city limits. The city area in the lower end of the Apple Creek subwatershed (as indicated
in the 2012 TMDL) was determined using the associated 2012 TMDL baseline for TP and TSS
loads in this subwatershed to back-calculate acreage of the Lawrence footprint.
16 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Figure II-2. The 40 sub-HUC-12 watershed delineations to address 303(d) listed waters and approved TMDL points of
standards application.
To obtain current loads of TP and TSS from the MS4 areas, the 2012 TMDL document was used
to derive the acre/year TP and TSS loading with the total MS4 acreage and total loadings from
each HUC-12 (or the corresponding TMDL subwatershed). For Ashwaubenon, Dutchman, and
Duck Creek watersheds, some MS4 areas were located in the Oneida Reservation. The TMDL
had different loading rates for the reservation and non-reservation MS4 areas in these HUC-12
equivalent watersheds. Area weighted average loadings were therefore used in these watersheds,
17 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
except for Ashwaubenon, where the city of Hobart was the only MS4 partially located in the
reservation. The TMDL loading rates for Ashwaubenon’s Oneida portion was used directly for
Hobart and the non-reservation rate was used for the remaining MS4 areas.
After the MS4 footprint and loading rates were determined, TP and TSS loads from the MS4
footprint in each of the sub HUC-12 watersheds were calculated as the product of the area and
loading rates. The analysis considered 86 MS4 discharge areas with a total land area of 163,593
acres. The total TP load was 101,792 pounds/year, with a TP load reduction goal based on the
2012 TMDL of 32,805 pounds/year (32.3% reduction across the entire LFRW). The total TSS
load was 46,907 tons/year, with a TSS load reduction goal based on the 2012 TMDL of 21,920
tons/year (47.6% reduction across the entire LFRW).
The resulting data were organized into tables and maps to present MS4 results of the 40 sub-
HUC-12s to meet the 2012 TMDL requirements for TP and TSS. These tables are presented in
the MS4 Demand Analysis Results later in this section.
MS4 Cost of Reduction Assessment Methods
A total cost evaluation was completed for those MS4s required to reduce phosphorus loading in
order to comply with the TMDL. The selected load-reduction technology for stormwater was
retention ponds installed within existing urban areas (e.g., existing residential neighborhoods,
commercial areas, etc.). Generally, it was assumed these ponds would be constructed within
available open parkland or green space to provide treatment for existing stormwater outfalls.
This was a default condition as only limited data were provided to the Project Team by MS4s,
their representatives or others for alternative options to be considered in this analysis. This
default approach was considered reasonable given that other potential alternatives yield highly
variable efficiencies and costs and have not yet been widely proposed in the basin.
The stormwater cost analysis incorporated several assumptions including:
Retention ponds would be designed as landscaped “wet” ponds (i.e., with permanent
pools)
Excavation/grading requirements and land area requirements for stormwater management
facilities were based on assumptions regarding typical depth, length/width ratio,
sideslopes and perimeter maintenance buffers
Sizing was based on modeling results developed in the 1990s by the Ontario Ministry of
Environment (MOE) using stormwater settleability data from the US EPA NURP studies
Pond sizing guidelines were used for achieving 80% TSS load reductions. For catchment
areas with 35% imperviousness, the guideline was a treatment volume of 2,700 ft3/acre
(equaling 0.74 inches of runoff)
It was assumed that retention ponds would provide 50% TP load reductions based on data
presented in the International Stormwater BMP Database July 2012 technical report
(Geosyntec, 2012). The report indicates the median and 75th
percentile values are around
18 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
60%. The conservative assumption of 50% TP reduction was selected in recognition of
the many challenges associated with retrofitting urban BMPs in already developed areas.
These assumptions compared favorably with the WI DNR wet detention pond practice standard
(1001) and the one community stormwater implementation report provided. The results are also
within the range of findings provided in a summary sheet of 35 wet detention ponds compiled by
the WI DNR for the LFRW. The summary list of wet detention ponds included eight sites with
modeling results for treatment performance. Such summary information is used for urban
stormwater grant tracking purposes by WI DNR.
The MS4 stormwater treatment cost assessment developed an estimate of capital cost and land
area required for average facilities in each of six classes: catchment areas less than 10 acres, 10-
50 acres, 50-125 acres, 25-500 acres, and greater than 500 acres. Capital cost was estimated as
construction cost plus 30%, to allow for design and contingencies. No land cost was included.
For each MS4 area, it was determined what fraction of the total land area would need to be
subject to stormwater treatment to achieve the TMDL goal. In addition, for each MS4 area, an
assumption was made regarding how many stormwater management facilities within each size
class would be required. The general assumption was that there would be bias toward facilities
that treat catchments in the size range of 10-50 acres, with fewer facilities in the other size
classes.
Cost estimates also incorporated one-time capital costs and annual operation and maintenance
costs. The annual estimated operation and maintenance costs included:
Routine inspections and reporting
Landscape maintenance (grass cutting, etc.) and litter/debris removal as needed
Sediment removal from facility, including all costs associated with necessary dewatering,
sediment handling, transport and disposal (e.g., at licensed landfill as required), assuming
forebay cleanout once every 10 years, main cell cleanout once every 30 years, with
associated costs translated to equivalent annual cost
Costs for influent and effluent monitoring to verify performance
For commercial and industrial development or other specific land uses, cost estimates were
developed for each MS4 area on the assumption that each MS4 was comprised of some mix of
residential, commercial/industrial/institutional (ICI) and open space/parkland/green space. It
was assumed that at this larger scale, the typical or representative impervious area was around
35% and thus, estimates were based on the associated set of costing numbers. Finer resolution of
land use was not made available for the MS4 areas. As such, the 35% value was considered the
most reasonable to apply at the MS4 spatial scale in which the average MS4 area was 1,902 acres
with a median of 1,267 acres.
MS4 Demand Analysis Results
A summary of the MS4 demand analysis is presented in Table II-6.
19 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table II-6. Results from MS4 demand analysis.
Analysis Result Assumptions
Total area of all MS4s 163,592 acres 86 reaches with MS4
discharges
Total area to be subject to stormwater
treatment to achieve TMDL goals for TP
and TSS
112,776 acres Based on stormwater
management retention ponds
that achieve 50% TP and 80%
TSS load reductions
Estimated number of individual stormwater
management facilities required
1,021 Averages 110 acres/facility
Estimated total capital cost $740 million Average $720,000/facility;
$6,600/catchment acre
Estimated total land area required for
stormwater management facilities
2,400 acres 1.4% of land area
The potential demand summary results for TP are presented in Table II-7; summary results for
TSS are presented in Table II-8. The wet detention pond treatment process reduces both TP and
TSS. Therefore, the costs in Tables II-7 and II-8 are not compounding. Typically, a community
will desire a reduction in loading for both parameters. As such, the unit costs of the combined
treatment may be a better reflection of the true unit cost. Detailed reduction/cost tables for each
MS4 by the 40 sub-HUC-12 watersheds are provided in Appendix B.
Table II-7. Total phosphorus demand and estimated cost for each MS4 to meet 2012 TMDL WLA reduction goals.
Total Phosphorus Reduction Requirements
Permitted
MS4
Urban
Contributing
Area (acres)
Estimated
TP
Reduction
Required
(lbs/yr)
Annualized1
Cost for Wet
Detention
Ponds
Land
Area
Required
for
BMPs
(acres)
Allouez 3,277 628 $ 1,761,000 53
Appleton 15,389 3,365 $ 7,714,000 246
Ashwaubenon 8,196 1,568 $ 3,913,000 118
Bellevue 6,612 1,392 $ 1,228,000 86
Buchanan 2,311 1,028 $ 2,065,000 64
Combined Locks 1,513 434 $ 1,091,000 32
DePere 7,987 1,496 $ 3,786,000 118
Grand Chute 8,502 1,873 $ 3,773,000 123
Green Bay 28,733 5,698 $ 12,295,000 383
Greenville 2,857 641 $ 1,487,000 47
Harrison 1,718 805 $ 1,339,000 43
20 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Hobart 20,837 3,370 $ 8,887,000 273
Howard 11,832 1,995 $ 4,479,827 140
Kaukauna 5,171 1,135 $ 2,583,000 80
Kimberly 1,597 369 $ 1,169,000 34
Lawrence 2,103 389 $ 1,101,000 31
Ledgeview 859 181 $ 5,480,000 17
Little Chute 3,699 701 $ 630,000 43
Menasha 3,864 743 $ 1,198,000 62
Neenah 5,272 875 $ 1,962,000 75
Scott 1,028 205 $ 497,000 14
Suamico 8,719 1,483 $ 3,137,000 97
T. Menasha 7,962 1,583 $ 3,613,000 120
T. Neenah 4,092 688 $ 1,977,000 60
UWGB 804 160 $ 474,000 13 1 Annualized cost methods based on current dollar life-cycle cost analysis using a 20-year life of project, 3.30%
inflation rate and a 6% nominal discount factor. The annualized cost estimate includes capital, operation and
maintenance costs.
Table II-8. TSS demand and estimated cost totals for each MS4.
Total Suspended Solids Reduction Requirements
Permitted
MS4
Urban
Contributing
Area (acres)
Estimated
TSS
Reduction
Required
(tons/yr)
Annualized1
Cost for Wet
Detention
Ponds
Land
Area
Required
for
BMPs
(acres)
Allouez 3,277 271 $ 1,761,000 53
Appleton 15,389 1,374 $ 7,714,000 246
Ashwaubenon 8,196 515 $ 3,913,000 118
Bellevue 6,612 361 $ 1,228,000 86
Buchanan 2,311 197 $ 2,065,000 64
Combined Locks 3,513 313 $ 1,091,000 32
DePere 7,987 682 $ 3,786,000 118
Grand Chute 8,502 348 $ 3,773,000 123
Green Bay 28,733 1,973 $ 12,295,000 383
Greenville 2,857 110 $ 1,487,000 47
Harrison 1,718 141 $ 1,339,000 43
Hobart 20,837 789 $ 8,887,000 273
Howard 11,832 497 $ 4,479,827 140
Kaukauna 5,171 492 $ 2,583,000 80
Kimberly 1,597 185 $ 1,169,000 34
Lawrence 2,103 98 $ 1,101,000 31
Ledgeview 859 66 $ 5,480,000 17
Little Chute 3,699 291 $ 630,000 43
Menasha 3,864 469 $ 1,198,000 62
21 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Neenah 5,272 386 $ 1,962,000 75
Scott 1,028 50 $ 497,000 14
Suamico 8,719 413 $ 3,137,000 97
T. Menasha 7,962 831 $ 3,613,000 120
T. Neenah 4,092 315 $ 1,977,000 60
UWGB 804 39 $ 474,000 13 1 Annualized cost methods based on current dollar life-cycle cost analysis using a 20-year life of project, 3.30%
inflation rate and a 6% nominal discount factor. The annualized cost estimate includes capital, operation and
maintenance costs.
Though this assessment was completed assuming 35 percent impervious surfaces built up
downtown areas and industrial districts can have impervious surface coverage as high as 70 to 90
percent. These higher percent impervious areas make it difficult to locate acceptable sites for
large detention facilities and thus increase the likely cost of treatment. Costs associated with
stormwater treatment for various catchment area sizes and impervious surface percentages of 35
and 70 percent are presented in Tables II-9a and II-9b. Table II-9b is limited to smaller class
sizes reflecting the difficulty sighting a large facility in a heavily built up area.
Table II-9a. Capital, operation and maintenance costs for stormwater wet detention pond facilities treating runoff from
areas with 35 percent impervious surfaces.
Size
Class
Class Range
(Catchment
Area--acres)
Mean
Catchment
Area (acres)
Estimated
Capital Cost
($)
Estimated
Capital
Cost
($/Acre)
Estimated
Average
Annual
O&M Cost
($)
Mean
Facility
Land Area
Required (acres)
1 <12 acres 6.2 $162,500 $65,000 $33,159.75 0.88
2 12-49 acres 31 $446,000 $35,683 $70,086.25 1.25
3 49-124 acres 87 $698,000 $19,929 $71,753.50 2.14
4 124-247 acres 185 $1,096,000 $14,617 $81,973.13 3.37
5 247-494 acres 371 $1,677,000 $11,180 $83,362.50 5.62
6 >494 acres 561 $2,310,000 $10,178 $92,513.85 7.79
22 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table II-9b. Capital, operation and maintenance costs for stormwater wet detention pond facilities treating runoff from
areas with 70 percent impervious surfaces.
Size
Class
Class Range
(Catchment
Area--acres)
Mean
Catchment
Area (acres)
Estimated
Capital Cost
($)
Estimated
Capital
Cost
($/acre)
Estimated
Average
Annual
O&M Cost
($)
Mean
Facility
Land Area
Required (acres)
1 <12 acres 6.2 $190,000 $65,000 $33,000 0.88
2 12-49 acres 30.9 $573,000 $35,700 $70,500 1.25
3 49-124 acres 86.5 $866,000 $19,900 $72,600 2.14
4 124-247 acres 185.3 $1,641,000 $14,600 $83,300 3.37
Table II-10 summarizes the range of unit costs that were identified in the LFRW through this
analysis. (Unit costs for removing TP and TSS from stormwater using wet detention ponds are
presented in Appendix B.) It is important to note that unit cost values presented reflect the BMP
sizing that achieves the most restrictive water quality parameter reduction need regarding TP or
TSS. As such, the unit cost estimate reflects the total cost of the treated area necessary for the
most restrictive parameter divided by the units of mass reduced even though the area treated
might have been determined by the other parameter. Therefore, the unit costs at the high end of
the range may not always be an efficient approach for that parameter. MS4 communities should
explore the use of different BMPs that are appropriate for the catchment characteristics and
community goals. When doing so, a unit cost evaluation for the BMPs being considered is
recommended.
Table II-10. Estimated low, medium and high annualized unit costs for TP and TSS for stormwater reductions.
Value TP unit cost ($/lb) TSS unit cost ($/ton)
Combined TP and TSS unit
cost ($/[lb TP + ton TSS])
Low $ 880 $ 3,400 $ 700
Medium $ 2,400 $ 7,800 $ 1,798
High $ 3,480 $ 13,500 $ 2,555
1 Annualized cost methods based on current dollar life-cycle cost analysis using a 20-year life of project, 3.30%
inflation rate and a 6% nominal discount factor. The total cost includes siting, design, capitalization and annual
operation and maintenance.
23 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
III. SUPPLY ASSESSMENT
Credit supply in trading programs is influenced by a number of factors, including source types
(e.g., animal operations versus crops), regulatory constraints (e.g., TMDL load allocations setting
baselines and load calculation requirements), physical location (e.g., upstream-only crediting)
and socio-economic factors (e.g., willingness to participate). Towards these ends, the Project
Team estimated the TP and TSS reduction potential for various nonpoint source sectors in the
watershed capable of potentially generating credits for sale through a WQT program.
Constraints reflected the 2012 TMDL, Wisconsin trading guidance (2013a) and direction by the
GLC and PMT.
The highest credit-generating capabilities examined in the assessment were associated with
agricultural fields and livestock operations. Also assessed was gully and streambank erosion.
WWTFs willing to go beyond their WQBEL requirements to generate point source credits were
ultimately not considered for this analysis due to the limited amount of facility information
available. However, WWTF representatives are strongly encouraged to consider credit
generation, if feasible, based on knowledge of their facility.
Other TP and TSS source types that might be capable of producing a credit supply mentioned,
but not analyzed in this report, include regulated and unregulated urban stormwater sources
(though such opportunities are likely limited), wetland creation, or restoration and activities in all
of the subwatersheds located above Lake Winnebago. A supply assessment associated with
these latter sources was beyond the scope of this feasibility assessment which focuses only on
the LFRW. Some discussion of trading opportunities above Lake Winnebago is provided in a
later section on “Considerations and Recommendations for Other Potential Credit Suppliers.
Ag and Rural Area Potential Credit Supply Overview
The assessment of potential rural area credit supplies in the LFRW required an analysis of
various nonpoint sources that were not specifically delineated in the 2012 TMDL. Thus, loading
associated with current practices needed to first be assessed followed by application of practices
required to initially meet TMDL load allocation reductions. Once TMDL reduction goals could
be met, application of additional BMPs and conservation practices to generate credits was
assessed to determine rural nonpoint source credit supply. The sequence of credit supply
analysis included assessment of:
TMDL load allocation reductions from rural sources
TMDL load allocation total costs
Maximum credit potential and total cost from agricultural cropping operations
Maximum credit potential and total cost from Animal Feeding Operations
Maximum credit potential and total cost from bank erosion and riparian gullies
24 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
The supply evaluation for agricultural and rural sources followed WI DNR trading guidance
(2013a) as well as 2012 TMDL constraints. The evaluation also relied upon approved credit
calculation methods and models. These included the University of Wisconsin cropland model,
SnapPlus v.2, and the Wisconsin Barnyard Runoff Model (BARNY) for barnyard nutrient
loading predictions, both designed for site-specific calculations. These models are part of the
Wisconsin DNR-approved calculation model list. When combined with the GIS spatial analyses
utilized herein for the broader feasibility assessment, site-specific loading inputs were replaced
with representative values (averages) selected by an Agricultural Oversight Subcommittee for
basin-wide credit supply assessment. Ultimately, each water quality trade must rely upon site-
specific analysis of local conditions and not on basin-wide analyses.
The primary purpose of SnapPlus was for nutrient management and conservation planning for
croplands based on the field’s dominant soil. It was developed for ranking fields by the
phosphorus pollution potential of their most "problematic" areas and not for quantifying whole
field P delivery from complex landscapes. An updated SnapPlus v.2 alternatively provided a “P
trade report” estimate of edge-of-field TP load for water quality trading applications using the
field’s dominant soil type with a simplified delivery ratio for infield attenuation.
SnapPlus v.2 also allowed for the prediction of TSS loads from the RUSLE2 model embedded in
the tool. Estimates of infield erosion (though without edge-of-field delivery factors) were used
for estimating TSS credit supply from cropland in the LFRW.
SnapPlus model output, coupled with GIS spatial analysis, provided cumulative cropland load
estimates that were ultimately calibrated to a watershed loading summation of all rural TSS and
TP loading from the 2012 TMDL. This step ensured that cumulative field scale predictions
ultimately reflected rural nonpoint source loads reported in the 2012 TMDL.
For analyzing potential TP loads from AFOs using BARNY, and extrapolations of streambank
and gully erosion reductions for both TSS and TP, select watershed data provided by Ms. Sarah
Francart, Outagamie County LCD, were used by Project Team. These data included:
Survey results for the Kankapot Creek and Plum Creek watersheds for AFOs and
streambanks (sediment and phosphorus loadings from the streambank erosion sites were
estimated using the NRCS method-Wisconsin NRCS Field Office Technical Guide 11/03
while phosphorus loadings from AFOs were estimated using the BARNY model)
Location GIS coverage for the streambank erosion survey along with the survey results
A fixed format map of the surveyed AFOs was provided along with the survey results
Details of data applications for use with SnapPlus, BARNY and other extrapolations used in the
determination of current loads by nonpoint source categories, and then later for assessment of
credit supply are provided in the following sections of this chapter.
25 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Ag and Rural Potential Credit Supply Determination
K&A led Project Team efforts to assess rural TP and TSS loads and corresponding credit supply.
Rural sources included cropland, animal feeding operations (AFOs), streambank and riparian
gully erosion. The analysis of these sources included an assessment of both interim and long-
term available credit supply. In addition, the cost of credit supply was calculated to determine if
purchasing credits could be a cost-effective compliance option for permit-regulated entities
facing stricter discharge limits. The following subsections document the numerous
considerations and analytical steps that were used to determine loading conditions for credit
supply. These are followed by descriptions of other project outputs requested by GLC and the
PMT, and then results depicting credit supply from the various rural nonpoint sources.
Overview of Methods to Assess TMDL Load Allocation Reductions from Rural Sources
Load allocations in the 2012 TMDL dictate minimum required load reduction requirements from
rural sources. These TMDL reduction goals, in essence, become a critical consideration for
dictating trading baselines for nonpoint source TP and TSS credit generation. Knowledge of
rural land use practices was therefore critical for determining present conditions and existing
conservation practices, conservation practice needs for addressing future load reduction
requirements (that can also provide interim 5-year credits), and then additional practices beyond
the TMDL Load Allocation to generate surplus reductions suitable for long-term WQT credits.
As such, the first step in this assessment process was to form an Agricultural Oversight
Subcommittee to best inform the Project Team in these regards. The Subcommittee consisted of
representatives from the four County Land Conservation Departments (CLCDs), WI DNR and
DATCP staff.
Based on the knowledge and input provided by the Subcommittee, the Project Team determined
“typical” crop rotations and operational practices that constituted representative conditions in
each of the four counties contributing to the LFRW. These included land application of manure
assuming an equal split between fall and spring applications all with incorporation when applied
to non- perennial crops. Important data/manipulations used to assess cropland source loading
included:
Sub-HUC 12 watersheds for impaired stream segment drainages were delineated using
the same process as described in the MS4 demand analysis estimation methods discussion
USDA NASS Cropland Data Layer (CDL) coverages from 2003 to 2013 were
downloaded from the CDL website at
http://www.nass.usda.gov/research/Cropland/Release/index.htm; of the 11 annual data
layers, the 2013 to 2010 and 2005-2003 coverages were of 30 m resolution and the 2009-
2006 coverages were of 56 m resolution
The NRCS State Soil Geographic (STATSGO) soil coverage data were downloaded from
USDA NRCS GeoSpatial Data Gateway at
http://datagateway.nrcs.usda.gov/GDGOrder.aspx
26 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Recommendations for seven crop rotations commonly practiced in the watershed were provided
by the Agricultural Oversight Subcommittee and used in this analysis. These are presented in
Table III-1.
Table III-1 Crop rotations selected by the Agricultural Oversight Subcommittee for the credit supply analysis.
Rotation
# Crop Crop Crop Crop Crop Crop Crop Crop
1 Corn
Grain
Corn
Silage
Corn
silage
Alfalfa
seeding Alfalfa Alfalfa Alfalfa Alfalfa
2 Alfalfa
Seeding Alfalfa Alfalfa Alfalfa
Corn
Grain
Corn
Silage
3 Alfalfa
Seeding Alfalfa Alfalfa Alfalfa
Corn
Silage
Corn
Silage Soybean Wheat
4 Corn
Grain
Corn
Grain Soybean Wheat
5 Corn
Silage Wheat
Corn
silage
Alfalfa
seeding Alfalfa Alfalfa Alfalfa
6 Alfalfa
Seeding Alfalfa Alfalfa Alfalfa
Corn
Silage
Corn
Silage
Corn
Silage
Corn
Silage
7 Corn
silage
Corn
silage
Corn
silage
Corn
silage
These typical cropping conditions were simulated in the SnapPlus v.2 model on ten
representative soil map units each representative of the STATSGO soil groups. As applied, the
SnapPlus v.2 provided a “P Trade” report providing edge-of-field phosphorus loadings.
Soil test phosphorus (STP) results were an important input factor for SnapPlus runs. These were
selected by the Agricultural Oversight Subcommittee to be 15, 25, 40 and 65 ppm. These input
data were confirmed by obtaining local soil laboratory summary statistics. Summary statistics
revealed that there was an equal distribution of STP results across the LFRW (e.g., 25 percent
could be represented by each STP result). These SnapPlus v.2 scenarios also yielded estimates
for soil erosion within the field (i.e., not delivered to the field edge) via the Revised Universal
Soil Loss Equation v.2 (RUSLE2) embedded in SnapPlus.
Mr. Nick Peltier, Brown County LCD, provided SnapPlus v.2 simulation results for unit TP
loads using the P Trade report, and TSS loadings for 10 STATSGO soils based on the RUSLE2
model outputs. Each soil was divided into four initial soil test phosphorus levels (15, 25, 40, and
65 ppm) for each of the seven most common crop rotations in the watershed as recommended by
the Agricultural Oversight Subcommittee. These 10 soils cover 99.6% of the LFRW area.
The SnapPlus simulations included loadings from current soil and management conditions, a set
of tillage and cover crop management practices (spring vertical till, no-till, interseeded winter rye
cover crop, fall seeded cover crop, spring field cultivate, and spring chisel), and buffer strips
27 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
combined with tillage and cover crop practices. The initial tillage coverage was estimated by the
Agricultural Oversight Subcommittee and consisted of fall chisel and disc, fall chisel no disc and
no-till according to the crop rotation.
In tandem with developing a typical condition for farm operations and riparian area sources, a
GIS spatial analysis was developed to provide the ability to examine these typical conditions
across the LFRW. The spatial analysis allowed the typical condition data to be used by
georeferencing the site estimates with representative soil groups and National Agricultural
Statistics Service cropland data layers to support the SnapPlus field scale evaluation.
The Agricultural Oversight Subcommittee also provided guidance to estimate the current extent
of BMP implementation in barnyards in similar fashion as their cropland recommendations. The
WI DNR-approved BARNY model was used on an AFO inventory of Plum Creek and Kankapot
Creek to estimate the current phosphorus loading estimates from barnyard waste from these
areas. From each typical condition in these runs, a watershed yield (lbs TP/acre/year) was
estimated. The inventory of AFO sites in the Plum and Kankapot Creek watersheds was
extrapolated throughout the basin based on an assumption of equal distribution of the 2013
Agricultural statistics for county cow/calf numbers. These data sets were used to create loading
estimates based on the developed watershed yield information. A watershed extrapolation was
completed using the spatial analysis based on the estimated watershed yield for each typical
condition.
In addition, a streambank erosion and riparian gully inventory conducted by the County Land
Conservation Departments in Plum and Kankapot Creeks yielded summary statistics including
percentages of inventoried miles considered to be eroding along with TSS loading estimates.
The streambank and riparian gully summary statistics were extrapolated to other subwatersheds
with similar geomorphology. The cropland and streambank and gully estimations for TSS were
then calibrated by subwatershed using a mass balance approach based on the 2012 TMDL TSS
agricultural loading estimates. A TP calibration was similarly conducted for TP load estimates.
Explicit details on how loads were determined from these rural sources as just described, are
documented as follows. These steps illustrate the complex level of analysis that went into rural
TP and TSS source load calculations that were otherwise not available in the 2012 TMDL or
other documentation, but necessary in order to determine potential credit supply in the LFRW.
Detailed Methods to Assess Cropland Loads
The following steps were taken to analyze TP and TSS loads from crop rotation sequences for
cropland parcels in the LFRW:
Step 1: GIS analysis was used to extract corn, soybeans, alfalfa, pasture, and winter wheat from
the CDL dataset. These five crops/vegetation covers were chosen based on the Agriculture
Oversight Subcommittee’s recommendation for the seven most common crop rotations in the
watershed. The extracted CDL coverages were then converted to point coverages for each of the
28 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
11 years. One grid (pixel) from the CDL coverage was converted to one point. Each point
therefore has a crop designation of one of the five crops. (Loss of acreage from the other crops
during this process ranges from less than 2% for 2013 to 8% for 2006). (It should be noted here
that the CDL crop coverages did not distinguish corn grain from corn silage, nor did they specify
alfalfa seeding as a separate crop. In addition, the pasture land use type and alfalfa crop in CDL
were combined in the analysis as alfalfa.)
Step 2: Sequentially space-join different years of the extracted CDL coverage (from 2013
moving backwards to 2003). Because point locations remain constant from year to year for CDL
coverages with the same resolution, space-join was done by point overlapping the same point
over two sequential years. For example, if one point at a location in 2013 was corn and there
was a point at the same location in 2012, that was marked as alfalfa, then there was a crop
sequence of 2013-2012 being corn-alfalfa. After the space-join was completed for the 2013 and
2012 coverages, the resulting 2013-2012 sequence coverage was space-joined with the 2011
coverage to result in the 2013-2012-2011 crop sequence, which in turn was joined with the 2010
coverage to get the 2013-2010 four-year crop sequence. The process was repeated until all 11
years were analyzed. Each step resulted in a crop sequence coverage for the watershed that had
one more year of crop assignment. Because the longest recommended rotation had a crop
sequence of 8 years, the sequencing result from the 8 years of 2006-2013 was used in this
analysis.
Step 3: The crop sequence coverage for 2006-2013 was then distributed to the 40 sub HUC-12
watersheds and exported to individual Excel spreadsheets.
Step 4: An algorithm was developed using Visual Basic Application script to assign each parcel
of land in each of the sub HUC-12 watersheds (based on its eight-year crop sequence) to one of
the seven crop rotations provided by the Agricultural Oversight Subcommittee. The algorithm
followed the following procedure:
a. Searched for parcels of land that had CDL assigned land use/crop of alfalfa/pasture from
the second through the seventh year of the eight-year rotation sequence. If any of these
years was alfalfa/pasture without an immediate neighboring alfalfa/pasture, it was
deemed a cartographical error and the land parcel for that year was reassigned a
neighboring non-alfalfa/pasture crop. Random errors in large data sets can be created by
light spectrometry recording errors, database collation errors as well as naturally
occurring issues such as drowned out areas in fields being repopulated by volunteer
growth of grasses and/or other weeds.
b. Searched for land parcels with seven or eight years of alfalfa/pasture and removed these
land parcels for further analysis due to their limited potential of generating load
reductions for WQT. Approximately 36,000 acres were removed. These acres can
consist of road ditches, marginal lands not in production, irregular field edges and
permanent pastures or hay land. Most of these land uses will not be able to generate a
credit due to perennial vegetation nonpoint source loading already being very low and the
29 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
inability to implement effective reduction practices. In some settings, permanent pasture
and/or hay land could be improved by pasture stand management or nutrient management
BMPs, however, without an inventory of these sites, specifying the condition, estimation
of potential reductions was not feasible. The limited number of sites was not likely to
substantially affect the results of the cropland assessment.
c. Sorted the remaining parcels using a prioritized search of unassigned parcels. The order
of the search was selected based upon the crop percentage in the database and not the
rotation number:
o Rotation #7 was assigned to parcels with the last five years of the crop sequence
containing corn (2009-2013).
o Rotation #3 was assigned to parcels with corn and soybeans plus at least three
years of alfalfa/pasture.
o Rotation #5 was assigned to land parcels with corn and wheat plus at least three
years of alfalfa/pasture.
o Rotation #4 was assigned to land parcels where no alfalfa/pasture was present in
any of the eight years when the parcel had not already been assigned Rotation #7
in step 3.
o Rotation #2 was assigned to land parcels with two years of consecutive corn
followed by three years of alfalfa/pasture.
o Rotation #6 was assigned to land parcels with four years of corn and at least three
years of alfalfa/pasture.
o Rotation #1 was assigned to land parcels with three years of corn and at least
three years of alfalfa/pasture.
d. Checked the entire database to mark the remaining unassigned land parcels.
e. If the last year of the 8-year crop sequence (year 2013) for a land parcel was
alfalfa/pasture, it was not possible to tell what crop would be planted in the following
year. A sub-algorithm was developed to assign such land parcels to Rotation #1, 2, 3, 5,
or 6.
f. Looked for land parcels with the first year (year 2004) being the only alfalfa/pasture in
the 8-year crop sequence. These land parcels were assigned Rotation #4.
g. For land parcels with only two consecutive alfalfa/pasture in the 8-year crop sequence, a
sub-algorithm was developed to assign such land parcels to Rotation #1, 2, 3, or 5.
h. For land parcels with five or more years of alfalfa/pasture in the 8-year crop sequence, a
sub-algorithm was developed to assign such land parcels to Rotation #1, 2, 3, or 5.
i. For land parcels with at least three years of alfalfa/pasture in the 8-year crop sequence but
without any corn, a sub-algorithm was developed to assign such land parcels to Rotation
#1, 2, 3, or 5.
j. Checked to ensure no parcels had been assigned more than one rotation. If such a case
was found, it was dealt with individually.
Step 5: An ArcGIS model was built to link the rotation assignment for each parcel of land to its
geographic location and to create a GIS coverage layer that had the location and rotation
assignment for each parcel.
30 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Step 6: The rotation assignment coverage was then intersected with the STATSGO soil
coverage to create a coverage that had both rotation assignment and STATSGO soil type. This
coverage was used to calculate the area for each soil and rotation combination in each of the 40
sub HUC-12 watersheds.
Step 7: Based on the soil test phosphorus survey results from the three main counties in the
LFRW (Brown, Outagamie, and Calumet) provided by Mr. Nick Peltier (September 25, 2014), it
was estimated that soils in the watershed had roughly equal distribution of the four soil test
phosphorus levels used in the SnapPlus v.2 P Trade report based approach. Results from Step 6
were thus matched with the SnapPlus P Trade report results for each of the 280 rotation/soil
type/soil test phosphorus combinations to obtain the TP and TSS loadings from the cropland for
each soil/rotation combination in the 40 sub HUC-12 watersheds.
Step 8: Using the 2012 TMDL baseline load estimate for TSS, a calibration coefficient for each
subwatershed was determined to adjust the GIS spatial analysis totals with the 2012 TMDL.
The calibration adjusted down the RUSLE2 in-field current erosion rates to simulate both in-
field delivery ratios and attenuation factors for those fields located further from perennial
streams. The process provided a balanced mass budget estimate of cropland, streambank and
riparian gully erosion (the processes to estimate these other sources are described below).
Step 9: A mass budget calibration process was applied to the GIS spatial analysis results for TP
by subwatershed. Based on the 2012 TMDL baseline load estimate for TP, a balanced source
loading estimate was created for cropland, streambank and riparian gully erosion, and AFOs
discharges. (The other source estimation processes are described below.) Using the sediment
adjusted loading from Step 8 as a guide for the level of TP provided by streambank and gully
loading, a calibration coefficient for each subwatershed for TP was determined. SnapPlus v.2 P
trade reports already have an adjustment factor to address edge-of-field loading. However, this
additional calibration was necessary to reconcile the GIS spatial analysis technique with the 2012
TMDL assessment. In addition, as set up, the SnapPlus v.2 P Trade report approach used an
input assumption of 300 feet to the edge-of-field when in reality actual distances are highly
variable.
Detailed Methods to Assess Animal Feeding Operation Loads
For analyzing the potential credit supply from AFOs, the TP loading from this source was
determined using the following steps:
Step 1: Surveyed results of the number of AFOs and TP loading from these AFOs for the
Kankapot Creek and Plum Creek watersheds were distributed to the three counties (Brown,
Calumet, and Outagamie Counties), each of which has land within the watershed boundaries.
The phosphorus loading for each site from the BARNY model runs were included in the
inventory. The survey inventoried 93 AFO operations that spanned parts of three counties, each
containing multiple operations. The large sample population and multiple sites per county is a
31 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
strong indication that differences between county oversight (if any) were accounted for within
the results. It was reasonable to assume that the results were representative of each
topographical circumstance faced by operators in the LFRW. This assumption was based on the
large sample size of the data set and the substantial spatial extent the inventory covers.
Therefore, the AFO survey results of average pounds of TP loading for each county were
selected to estimate an AFO’s phosphorus load.
Step 2: The Project Team applied the loading estimate derived in Step 1, by cross referencing it
with the county data from the “All Cattle and Calves” category in the 2013 Wisconsin
Agricultural Statistics (USDA NASS, 2013). Based on assuming an equal distribution in
cattle/acre/county, the AFO survey TP loading estimate was converted into a pound TP per acre
estimate for each county. This form of the loading estimation was then adjustable based on the
Ag census head count for each county. This unit area loading rate was applied to other parts of
the county outside these two watersheds in Step 3.
Step 3: Geo-processing was performed to obtain the distribution of county areas in each of the
sub HUC-12 watersheds. The county unit area TP loading rates from AFOs were applied to
these areas to obtain the total TP loads from the sub HUC-12 watersheds. It is noted here that
there were some areas near the Neenah Slough that fell inside Winnebago County. Unit loading
rates for neighboring Outagamie County were used in these areas. One area in the upper East
River watershed fell inside Manitowoc County. Unit loading rates for neighboring Calumet
County were used in that area.
Detailed Methods to Assess Streambank and Riparian Gully Erosion Loads
The Plum and Kankapot Creek streambank and riparian gully inventory was used to extrapolate
erosion rates to other subwatershed areas that were considered to have appropriately similar
geomorphology characteristics. For analysis of streambank erosion and riparian gullies, TP and
TSS loadings from these sources were determined using the following steps:
Step 1: According to the information provided to the Project Team, the stream survey conducted
by the Outagamie County LCD for the Plum Creek and Kankapot Creek watersheds targeted
30% of the total stream miles in the watersheds where bank erosion was likely. Of these targeted
stream miles, 58% of them were eroding. TSS loading from the eroding banks was estimated
during the survey at an average rate of 187 tons per stream mile per year. It was further assumed
by the Project Team that the eroding sediment had a TP concentration of 0.5 pounds per ton.
Step 2: Based on GIS perspective maps and Agricultural Oversight Subcommittee concurrence,
it was determined that due to the mostly flat landscape of the LFRW, streambank erosion likely
took place in only the following HUC-12 watersheds:
Trout Creek
Lower Duck Creek
Upper East River
32 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Bower Creek
Baird Creek
Lower East River
Apple Creek
Garners Creek portion of the Fox-Garners HUC-12
Total stream miles were thus determined for these HUC-12 watersheds.
Step 3: TSS loadings from these HUC-12 watersheds were calculated based on the assumption
that 30% of total stream miles were susceptible to erosion and of these stream miles, 58% were
actually eroding at a rate of 187 tons of TSS per stream mile per year, with a TP concentration of
0.5 pounds per ton.
Universal Credit Threshold Analysis
The GLC PMT requested that the Project Team also provide guidance in the feasibility
assessment for development of a universal credit threshold (UTC) for cropland sources and a
credit threshold (CT) for AFOs and streambanks. Though this UTC and CT provide an efficient
trading baseline determination method (if ultimately deemed appropriate by WI DNR), the
estimated factors derived here were not used in the final demand/supply comparisons. Rather,
the approach and computations are provided to GLC and the PMT in this report for their other
trading policy deliberations. In these regards, the Project Team elaborates on the concept of a
UTC and CT as follows.
By establishing a unit load average for each credit generating source, early adopters of
conservation would essentially not be penalized by having to make further reductions to achieve
the 2012 TMDL load allocations. These early adopters could also potentially sell credits based
on the margin that exists between their sites current nonpoint source edge of field loading and the
higher UCT or CT. The following equations were provided by the PMT to consider in these
regards:
For gullies/concentrated flow channels, AFOs, and bank erosion, the EPA-approved
TMDL percent reduction targets for agriculture were applied using the formula P-R=CT,
where:
o P = lbs/year being discharged
o E = EPA-approved percentage load reduction
o R (amount needed to be reduced to achieve credit threshold) = P x E
o CT (credit threshold) = P – R
For cropland sheet and rill erosion, the non-cropland sources were subtracted from the
baseline to estimate cropland area and develop a universal credit threshold (UCT) for
each subwatershed. This considered: average phosphorus index for the watershed,
baseline load of phosphorus and TSS (e.g., lbs/year) and acres in cropland production.
The formula applied was UCT = API x (100-E), where:
33 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
o API (average phosphorus index) = B/Ag
o B – baseline lbs/year for Ag in TMDL subwatersheds
o Ag = Ag acres in HUC-12
The Project Team could not assess concentrated flow channels. Early in the project, discussions
were held that indicated that the County Land Conservation Departments had run GIS terrain
analysis using the Stream Power Index (SPI) for Plum Creek. SPI terrain analysis can be used to
determine vulnerable sites in upland fields that may be susceptible to channelized flow erosion
and NPS loading concerns. However, for the Project Team to successfully evaluate loading from
GIS SPI analysis, two other information sets were necessary. The first dataset was a field
verification such that the SPI priority rankings selected in the terrain analysis were in the correct
range to be associated with a high probability of channelized flow concerns (e.g., gully formation
and/or snow melt seasonal ephemeral channels). This field verification should also provide a
check on the SPI process dividing the GIS terrain analysis into bins of confirmed field
vulnerability, the sites already treated with BMPs and/or a false positive GIS ranking. The
second necessary information set was a correlation between the prioritized ranking of the GIS
terrain analysis and the estimated field loading from channelized flow conditions.
The Plum Creek data did not have either of these required additional information sets. In
addition, extrapolation of the Plum Creek terrain analysis and inventories outside of this
subwatershed raised accuracy concerns. Therefore, the Project Team settled on using the
streambank erosion inventory in Plum Creek and Kankapot Creeks as described above. The
County Department staff estimated that five percent of the TSS loading was determined to be
coming from riparian gullies. This estimate was based on identified eroded soils connected to
streams located in upland areas. It was recognized here that this did not fully address
channelized flow concerns with soluble phosphorus loadings from land application of manure in
the flow path or high STP soils releasing soluble phosphorus.
Based on the GIS spatial analysis described above, the spatially distributed load based on the
SnapPlus GIS projections calibrated to the 2012 TMDL baseline were used for each HUC-12
watershed. SnapPlus contains a delivery ratio in its phosphorus estimates. However, as it was
applied in the GIS spatial analysis, a 300-foot length of field was assumed. This implies that the
field is adjacent to a perennial stream which is not always the case. Therefore, the sum of the
distributed SnapPlus field loadings as determined by the GIS spatial analysis was adjusted down
to reflect the 2012 TMDL current conditions. The average of the adjustments was a 30 percent
reduction in HUC-12 GIS spatial analysis loading for phosphorus.
[Note: This procedure was a necessary step to calibrate the loading for each subwatershed
comparison. However, future credit supply searches should prioritize fields adjacent to streams
high on the list. These settings will yield the highest per acre field reduction as predicted by
SnapPlus, without having to be further discounted by an upland attenuation factor similar to the
one used here.]
34 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
The adjusted SnapPlus GIS spatial analysis current load for each subwatershed was calculated
and then reduced by the 2012 TMDL reduction requirements. Next, the calibrated mass budget
for the subwatershed was used to determine the average unit loading rate (i.e., pounds
TP/acre/year) that would achieve the load allocation. Finally, the unit loading rate was divided
by the mass budget calibration coefficient for each subwatershed to provide the SnapPlus edge-
of-field universal phosphorus loading rate (lbs TP/acre) that would achieve the 2012 TMDL
goals and objectives. These calculated credit thresholds are presented in Table III-2.
Table III-2. Cropland universal credit threshold and Animal Feeding Operation, streambank and gully credit thresholds
by TMDL subwatersheds.
TMDL Subwatershed
In-field Cropland
Universal Credit
Threshold for SnapPlus
Results [Based on the
Calibrated Load
Estimates]
(lbs TP/acre)
Subwatershed Credit
Threshold for AFO
(lbs TP/Subwatershed)
Subwatershed
Aggregate Credit
Threshold for Bank
Erosion & Riparian
Gullies
(lbs TP/Subwatershed)
Apple Creek 2.04 98 213
Ashwaubenon Creek 1.86 111
Baird Creek 2.08 84 15
Bower Creek 1.81 124 206
Upper Duck Creek 1.72 165
Middle Duck Creek 1.85 88
Lower Duck Creek 1.25 42 341
Oneida Creek 1.24 44
Dutchman Creek 2.13 107
Upper East River 2.11 106 147
Lower East River 1.90 127 173
Dead Horse Bay-Frontal Green Bay 0.53
81
Point du Sable-Frontal Green Bay 1.53
165
*City of Green Bay-Fox River 1.31 135
*Garners Creek-Fox River 1.19 167 58
Kankapot Creek 1.85 113 151
*Little Lake Butte des Mortes 1.16 120
*Mud Creek 0.66 124
Plum Creek 2.18 91 219
Trout Creek 0.69 95 78 * Subwatersheds that have substantial differences in the SWAT model boundaries in the 2012 TMDL compared to USGS GIS
HUC-12 boundaries. The GLC PMT and WI DNR may consider using a different approach when the credit thresholds are
determined within these subwatersheds.
For gullies, AFOs, and streambank erosion, the long-term credit threshold available from one
site’s implementation could be reduced to calculating the total credits available from the
35 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
corrective actions and then multiplying the 2012 TMDL load allocation reduction goal.
However, when an entity is pursuing a substantial number of site’s, Table III-2 could be used to
identify the tipping point at which time the next site correction is eligible for the entire load
reduction to generate long-term credits.
Results of BMP Implementation Reductions on Croplands
This analysis recognized interim (5-year) crediting opportunities under Wisconsin Trading
Guidance as agricultural production strives to achieve the 2012 TMDL load allocation; and
subsequently, long-term (post 5-year practice implementation) credit generation where the load
allocation becomes the farmers’ new crediting baseline. To estimate the total cost of achieving
the 2012 TMDL load allocation, USDA-NRCS 2014 practice information for Wisconsin was
used in this LFRW application. Specifically, the USDA-NRCS Environmental Quality
Incentives Program (EQIP) payment schedules for 100 percent of practice capital costs were
applied. To collect total cost estimates, operation and maintenance costs were assumed to be
four (4) percent of the BMP capital cost.
The Agricultural Oversight Subcommittee and Project Team collaborated to first develop a
cropland BMP system that would be acceptable for Ag producers to meet the TMDL reduction
goals. Again, TMDL reduction goals needed to be met before trading credits could be generated
in this scenario (recognizing the initial 5-year window for credits following practice
implementation). The BMP development process was iterative. The first two attempts did not
achieve the 2012 TMDL load allocations in many of the LFRW subwatersheds. The third BMP
system including buffers could potentially meet these goals at Green Bay. Buffers, however,
were not likely to be widely adopted without substantial incentives, according to the Agricultural
Oversight Subcommittee. Even with buffers being applied on all cropped land in the watershed,
the load allocation goals for phosphorus were still not achieved in a few subwatersheds. Table
III-3 shows the BMPs selected in the third cropland reduction scenario (BMP system 3). Tables
III-4 and III-5 provide the BMP system loading comparisons with the 2012 TMDL load
allocations for TP and TSS, respectively. The detailed estimates for reductions in the 40 sub-
HUC-12 watersheds are provided separately from this report in a MS ExcelTM
workbook
entitled: Interim and Long-term Credit Supply and Demand Comparisons.
The inability for BMP system 3 to achieve the total phosphorus load allocation in all areas with
what was considered to be an overly optimistic implementation plan for croplands limits the
ability to generate long-term phosphorus credits for some of the 40 subwatersheds.
36 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-3. BMP system 3 list of individual BMPs applied for each crop rotation by year of application.
Rotation
# Crop Crop Crop Crop Crop Crop Crop Crop
Edge-of-
field
1 Corn Grain
(svt)
Corn Silage
(cc)(svt)
Corn silage
(cc)
Alfalfa
seeding (sfc) Alfalfa Alfalfa Alfalfa Alfalfa Buffer
2
Alfalfa
Seeding
(svt)
Alfalfa Alfalfa Alfalfa Corn Grain
(svt)
Corn Silage
(svt)(cc) Buffer
3
Alfalfa
Seeding
(sfc)
Alfalfa Alfalfa Alfalfa Corn Silage
(cc)(svt)
Corn Silage
(cc)(svt)
Soybean
(svt) Wheat (nt) Buffer
4 Corn Grain
(nt)
Corn Grain
(nt)
Soybean
(nt) Wheat (nt) Buffer
5 Corn Silage
(svt)
Wheat
(nt)(cc)
Corn silage
(nt)(cc)
Alfalfa
seeding Alfalfa Alfalfa Alfalfa Buffer
6 Alfalfa
Seeding Alfalfa Alfalfa Alfalfa
Corn Silage
(scl)
Corn Silage
(scl)
Corn Silage
(winter rye
2nd
crop)
(sfc)
Corn Silage
(winter rye
2nd
crop)
(sfc)
Buffer
7 Corn silage
(cc)(nt)
Corn silage
(inter-
rye)(nt)
Corn silage
(cc)(nt)
Corn silage
(inter-
rye)(nt)
Buffer
svt = Spring vertical till; nt = No-till; inter rye = Interseeded winter rye cover crop; cc = Fall seeded cover crop; sfc = Spring field
cultivation; scl = Spring chisel plow
37 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-4. Total phosphorus reduction estimates for croplands in each HUC-12 subwatershed (shaded red boxes emphasis where TMDL load allocations cannot be
met).
Subwatershed
TMDL
Reduction
LA Goal
Total Area
(Acres)
GIS
Analysis
Baseline
(lbs TP/yr)
TMDL %
Reduction
Goal Applied
to Croplands
(lbs TP/yr)
TP Loading for BMP
System with Buffer &
Nut. Mgt. (65ppm to
45ppm)
(lbs TP/yr)
Compliance
with
TMDL?
(Est. Based
on BMP
System 3)
Plum Creek 86.0% 13,104 25,857 3,564 6,173 No
Kankapot Creek 81.8% 8,565 15,632 2,845 3,723 No
Apple Creek 78.6% 15,209 25,857 5,533 5,669 Yes
Bower Creek 83.2% 11,932 20,975 3,524 5,412 No
Trout Creek 54.9% 3,481 2,891 1,304 854 Yes
Mud Creek 39.0% 2,509 1,681 1,025 388 Yes
City of Green Bay-Fox River 74.2% 2,538 5,354 1,383 1,346 Yes
Garners Creek-Fox River 63.1% 2,548 4,543 1,677 1,065 Yes
Upper East River 83.9% 12,000 21,680 3,491 5,213 No
Lower East River 83.9% 7,911 12,921 2,080 3,187 No
Dutchman Creek 76.4% 7,073 9,676 2,283 1,963 Yes
Upper Duck Creek 76.9% 16,307 23,757 5,488 5,221 Yes
Middle Duck Creek 76.9% 6,672 10,470 2,418 2,392 Yes
Lower Duck Creek 76.9% 3695 3,924 906 1,107 No
Oneida Creek 76.9% 7,773 8,203 1,895 2,060 No
38 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Dead Horse Bay-Frontal Green Bay
60.7% 294 187 73 54 Yes
Point du Sable-Frontal Green Bay
60.7% 4,342 7,860 3,089 1,516 Yes
Little Lake Butte des Mortes 66.7% 4,748 7,651 2,548 1,825 Yes
Baird Creek 80.4% 5,574 8,519 1,670 1,915 No
Ashwaubenon Creek 74.0% 9,916 11,844 3,079 2,711 Yes
Table III-5. Total suspended solids reduction estimates for each HUC-12 subwatershed (shaded red boxes emphasis where TMDL load allocations cannot be met).
Subwatershed
TSS TMDL
Reduction
LA Goal
Total
Area
(Acres)
GIS
Analysis
Baseline
(Tons/yr)
TMDL %
Reduction
Goal Applied
to Croplands
(Tons/yr)
Total Sum BMP
System TSS Loading
(Tons/yr)
Compliance
with TMDL?
Plum Creek 74.6% 13104 2465 626 256 Yes
Kankapot Creek 67.4% 8565 1412 460 145 Yes
Apple Creek 56.1% 15209 2739 1202 257 Yes
Bower Creek 67.3% 11932 1794 587 198 Yes
Trout Creek 12.3% 3481 266 233 18 Yes
Mud Creek 8.8% 2509 339 310 33 Yes
City of Green Bay-Fox River 61.9% 2538 1651 629 173 Yes
Garners Creek-Fox River 32.4% 2548 370 250 38 Yes
Upper East River 70.6% 12000 2365 695 247 Yes
39 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Lower East River 70.6% 7911 1342 395 131 Yes
Dutchman Creek 35.8% 7073 1435 921 122 Yes
Upper Duck Creek 58.6% 16307 3783 1566 362 Yes
Middle Duck Creek 58.6% 6672 1680 695 169 Yes
Lower Duck Creek 58.6% 3695 584 242 50 Yes
Oneida Creek 58.6% 7773 1331 551 102 Yes
Dead Horse Bay-Frontal Green Bay 47.1% 294 28 15 2 Yes
Point du Sable-Frontal Green Bay 47.1% 4,342 1,318 697 101 Yes
Little Lake Butte des Mortes 43.2% 4,748 1,360 773 140 Yes
Baird Creek 30.4% 5,574 925 644 88 Yes
Ashwaubenon Creek 39.7% 9,916 1,774 1,069 176 Yes
40 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Results of BMP Implementation Reductions for Animal Feeding Operations
The evaluation of AFO operations required a system of BMPs be developed to address the
nonpoint source loading from production areas. AFOs can release phosphorus in runoff which
comes in contact with manure at several points around the production area. The AFO BMP
package assembled for this study assumed the average small AFO requires:
Two BMPs to limit clean water from entering areas with manure
o Providing 150 feet of roof gutters
o Creating 200 feet of clean water diversion swales
Two BMPs to improve barnyard areas
o Providing an upgraded floor in the manure stacking area with concrete walls (the
average stacking pad area was assumed to be 15,000 square feet)
o Providing 150 feet of underground outlets for directing drainage from the
barnyard to the treatment system
A 20,000 square foot vegetative treatment system
A comprehensive nutrient management plan for proper land application of manure
The AFO sources of phosphorus are controllable without impacting production characteristics.
Therefore, the ability to meet the 2012 TMDL load allocations is limited only by producer
willingness and funding constraints. Table III-6 presents the current condition baselines and
2012 TMDL reduction requirements for phosphorus by subwatershed for AFOs. AFO TSS
reduction estimates are not considered in this analysis. (For comparative purposes, TP results for
streambank/gully erosion are also included in Table III-6.)
Results of BMP Implementation Reductions for Streambank and Riparian Gully BMPs
Installation methods assumed for streambank and riparian gully correction methods assumed
implementation of streambank and shoreline protection (NRCS Practice Standard 580; 4-7 feet
bank height) and grassed waterways (NRCS Practice Standard 412; drainage area 100-200
acres), respectively. The results for TP reduction estimates were presented in Table III-6,
sediment reduction results are presented in Table III-7. Table III-7 provides both current
condition baselines and 2012 TMDL reduction requirements for TSS by subwatershed for bank
erosion and gullies consistent with Table III-6.
41 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-6. AFO, streambank and gully current condition TP baseline and load allocation required reductions.
Subwatershed
TMDL
Reduction Load
Allocation Goal
AFO Baseline
Estimate
(lbs TP/yr)
AFO Load
Allocation
Required
Reduction
(lbs TP/yr)
Streambank and
Gully Erosion
Baseline Estimate
(lbs TP/yr)
Streambank and
Gully Required
Reduction
(lbs TP/yr)
Plum Creek 86.0% 650 559 1,561 1,342
Kankapot Creek 81.8% 620 507 830 679
Apple Creek 78.6% 456 358 994 781
Bower Creek 83.2% 740 616 1,227 1,021
Trout Creek 54.9% 211 116 172 94
Mud Creek 39.0% 203 79
City of Green Bay-Fox River
74.2% 523 388
Garners Creek-Fox River
63.1% 452 285 156 98
Upper East River 83.9% 660 554 910 763
Lower East River 83.9% 787 660 1,077 904
Dutchman Creek 76.4% 454 347
Upper Duck Creek 76.9% 715 550
Middle Duck Creek 76.9% 382 294
Lower Duck Creek 76.9% 183 141 1,476 1,135
Oneida Creek 76.9% 190 146
42 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Dead Horse Bay-Frontal Green Bay
60.7% 207 126
Point du Sable-Frontal Green Bay
60.7% 420 255
Little Lake Butte des Mortes
66.7% 361 241
Baird Creek 80.4% 431 347 74 59
Ashwaubenon Creek 74.0% 428 317
43 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-7. Streambank and gully TSS current condition baseline estimates and TMDL reduction requirements.
Subwatershed
Streambank and Gully
Erosion Baseline
Estimate
(tons TSS/yr)
Streambank and Gully
Required Reduction
(tons TSS/yr)
Plum Creek 3,122 2,329
Kankapot Creek 1,659 1,118
Apple Creek 1,988 1,115
Bower Creek 2,453 1,651
Trout Creek 344 42
Garners Creek-Fox River 311 101
Upper East River 1,819 1,284
Lower East River 2,153 1,520
Lower Duck Creek 2,952 1,730
Baird Creek 148 45
TMDL Implementation Cost Estimates
One condition of the Project Team’s scope was to estimate the total cost to achieve the 2012
TMDL agricultural load allocation. The estimate of the 2012 TMDL implementation total cost
was derived by summing all management practices used in the source category. The 2012
TMDL agricultural load allocation was for all agricultural and rural sources. The GIS spatial
analysis therefore subdivided the 2012 TMDL information into separate loadings for cropland,
AFOs, streambank and riparian gully sources. Thus, the total cost of the 2012 TMDL Ag load
allocation was based on the sum of annualized capital, O&M and replacement costs for each
BMP working within a source category. Most source categories applied multiple BMPs to
achieve the desired reduction. For instance, croplands had seven different crop rotations, each
crop rotation contains three or four different crops that are rotated using a four to eight year
cycle. Each individual crop year may have one or more BMPs applied to protect water quality.
The entire list of BMPs used throughout the rotation is referred to as a BMP system in this
report. Streambank stabilization and gully erosion protection are the only two sources that could
be addressed by implementing one BMP (e.g., riprap or bioengineering structures for bank
44 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
erosion and grassed waterways for gully prevention). The AFO cost estimation process
considered the total cost of six BMPs implemented as a system to address the AFO phosphorus
releases from multiple locations in a barnyard. The total cost for the BMP systems for each
source was then compiled.
Total costs are presented as an annualized cost based on the same life-cycle cost methods
described for WWTF demand. The cost analysis incorporated the total cost for each of the seven
rotations of BMP systems for cropland including implementation costs, operation and
maintenance costs, and transaction costs. This approach was used because each cropland BMP
only has a lifespan of one year per NRCS technical standard lifespans.
A lifecycle cost analysis was used to evaluate the cost of BMPs implemented for AFOs. This
analysis incorporated implementation costs, operation and maintenance costs, and transaction
costs for the total lifespan of each selected BMP. An inflation rate of 3.3% and nominal discount
rate of 6% (equivalent to a 2.6% real discount rate) was applied over a 20-year span, and the
resulting net present value was used to calculate an annualized cost ($/year).
The same lifecycle cost analysis approach was applied to determine an annualized cost for
streambank restoration and gully stabilization. Many BMPs have a project life that is shorter
than 20 years, so the BMP cost estimate included replacing the BMP at the end of its project life
until a 20-year period was covered.
Each component BMP system was evaluated to determine its capital and O&M cost. Then, the
individual components were summed to determine the BMP system’s total cost. Table III-8
presents the BMP system annualized cost results for cropland, AFO, streambank and gully
erosion.
Table III-8. Total cost and annualized cost summaries for agricultural and rural nonpoint source BMP systems.
Source
Type
Description / life
of practice Total Cost
Annualized
Cost
($/unit)
Cro
pla
nd
Rotation 1 / 7 yrs. $374 $53/acre
Rotation 2 / 6 yrs. $294 $49/acre
Rotation 3 / 8 yrs. $495 $62/acre
Rotation 4 / 4 yrs. $309 $77/acre
Rotation 5 / 7 yrs. $439 $63/acre
Rotation 6 / 8 yrs. $193 $24/acre
Rotation 7 / 4 yrs. $667 $167/acre
45 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
AFO Complete System /
20 yrs.
$74K $8.6K/system
Stream
Bank
Riprap for 4 to 7 foot
bank / 20 yrs.
$168K $18K/mile
Gully Grassed Waterway $971 $150/225 ft
The estimated total annual cost to implement the 2012 TMDL Ag and rural load allocation is
$42M. The estimate for cropland practices is an annualized cost of $9.8M, AFO corrections are
$30.9M and streambank and riparian gully corrections are $1.6M.
Credit Supply Volume Calculation Considerations
The credit supply evaluation is calculated for both the interim credits and long-term credits using
computations outlined above. The WI DNR guidance (WI DNR, 2013a) allows for reductions
implemented to achieve compliance with WI rules NR 151 and/or the 2012 TMDL load
allocation goals to also be eligible to generate interim credits (though limited to five years of
credit generation). After five years, a farm site is expected to maintain the current level of
nonpoint source loading without being able to generate credits based on these practices. At this
point in time, the interim credits end and become the new threshold (baseline) from which
further reductions are measured against to determine the generation of long-term credits.
Trade Ratio Determination to Calculate Credits from Reductions
To calculate both the interim and long-term credit generation capability of each of the four rural
sources, corresponding load reductions were multiplied by trade ratios developed following the
WI DNR guidance on calculation procedures. WI DNR guidance (Wisconsin DNR, 2013a)
states that a trade ratio for TSS and phosphorus is determined by the following equation:
Trade Ratio = (Delivery + Downstream + Uncertainty - Habitat Adjustment) : 1
Where:
Delivery: This factor accounts for the distance between trading partners and the impact
that this distance has on the fate and transport of the traded pollutant in surface
waters. This can be determined by the TMDL model information and/or the
USGS SPARROW model results where Delivery factor is equal to (one
divided by the SPARROW delivery fraction) minus 1.
Downstream: This trading factor is needed when the credit generator is located
downstream from the credit user’s point of standards application within the
same HUC-12 watershed.
46 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Uncertainty: This factor compensates for the multiple sources of uncertainty that
normally occur in the generation of credits by NPSs and is specific to the BMP
or BMP system being implemented.
Habitat Adjustment: This factor applies to surface waters listed on the WI DNR 303(d)
list. To qualify, the surface water must be listed by WI DNR as impaired for
the traded pollutant, and the management measure or practice must address
both the traded pollutant and specific habitat impairments.
This trade ratio can never be less than 1.2 to 1 when applied to a point to nonpoint source trade.
The calculated trade ratios by subwatershed for cropland and AFOs are presented in Table III-9.
The delivery factor was estimated by applying the delivery fraction results when using the USGS
SPARROW Decision Support System3 to determine incremental delivered yield (downstream).
The SPARROW Decision Support System results were used instead of the 2012 TMDL SWAT
model delivery factors due to the SWAT modeling results being unavailable. (Appendix C
provides the SPARROW application for this analysis.)
Several other trade ratio factors were not applied in this study. The WI DNR staff elected to use
the point of standards application for the 2012 TMDL and waters listed as impaired. Therefore,
the downstream factor was not appropriate. TP and TSS were assigned a zero for equivalency
factors in the WI DNR guidance document (2013a). (The habitat adjustment factor approach is
still being considered by the WI DNR. This reduction in trade ratio was not finalized at the time
of this writing.)
Table III-9. Cropland and AFO trade ratio development by subwatershed.
Subwatershed
Delivery
Factor
Uncertainty
Factor
Trade
Ratio
Mud Creek <0.1 2 2.0
Little Lake Butte des Mortes <0.1 2 2.0
Garners Creek <0.1 2 2.0
Dead Horse Bay-Frontal Green Bay 0 2 2.0
Upper Duck Creek 0.3604 2 2.4
Middle Duck Creek 0.1 2 2.1
Lower Duck Creek 0 2 2.0
Oneida Creek 0.1 2 2.1
Trout Creek 0.135 2 2.1
Kankapot Creek <0.1 2 2.1
Plum Creek <0.1 2 2.0
Upper East River 0.28 2 2.3
3 USGS Decision Support System, 2002 total phosphorus model for the Great Lakes, Lower Fox River. Available
on line at: http://cida.usgs.gov/sparrow/#modelid=42
47 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Bower Creek 0 2 2.0
Baird Creek 0 2 2.0
Lower East River 0 2 2.0
Point du Sable-Frontal Green Bay 0 2 2.0
Apple Creek <0.1 2 2.0
Ashwaubenon Creek <0.1 2 2.0
Dutchman Creek 0 2 2.0
City of Green Bay - Fox River 0 2 2.0
The calculated trade ratios by subwatershed for streambank erosion are presented in Table III-10.
Table III-10. Streambank erosion trade ratio development by subwatershed.
Subwatershed
Delivery
Factor
Uncertainty
Factor
Trade
Ratio
Mud Creek <0.1 3 3.0
Little Lake Butte des Mortes <0.1 3 3.0
Garners Creek <0.1 3 3.0
Dead Horse Bay-Frontal Green Bay 0 3 3.0
Upper Duck Creek 0.3604 3 3.4
Middle Duck Creek 0.1 3 3.1
Lower Duck Creek 0 3 3.0
Oneida Creek 0.1 3 3.1
Trout Creek 0.135 3 3.1
Kankapot Creek <0.1 3 3.1
Plum Creek <0.1 3 3.0
Upper East River 0.28 3 3.3
Bower Creek 0 3 3.0
Baird Creek 0 3 3.0
Lower East River 0 3 3.0
Point du Sable-Frontal Green Bay 0 3 3.0
Apple Creek <0.1 3 3.0
Ashwaubenon Creek <0.1 3 3.0
Dutchman Creek 0 3 3.0
City of Green Bay - Fox River 0 3 3.0
Interim and Long-term Credit Results
Table III-11 presents the results of applying these trade ratios to the watershed TP reduction
estimates to determine credits. Table III-12 presents these results for TSS credits. (These tables
48 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
include the Universal Credit Threshold values for informational purposes only and at the request
of GLC and PMT.)
Table III-11. Potential phosphorus credits generated by cropland BMPs (one credit offsets one lb TP/yr discharged by
the buyer). (A zero represents that the 2012 TMDL LA would not be achieved for croplands, a <10 value indicates the
analysis projected less than 10 credits and therefore the introduction of modeling uncertainty is too great to list the value
itself.)
ID HUC 12 Name
40
Sub-HUC-12
Description
Trade
Ratio
Universal
Credit
Threshold
(lbs
TP/acre)
Number of
Interim
Potential TP
Credits
Number of
Long-term
Potential TP
Credits*
0 Apple Creek Upper 2.0 2.04 8,210 0
1 Apple Creek Lower 2.0 2.04 1,884 72
2 Trout Creek Unimpaired 2.1 0.69 970 151
3 Point du Sable-Frontal Green Bay 2.0
1.53 3,172 635
4 Plum Creek Lower 2.0 2.18 8,730 0
5 Plum Creek Upper 2.0 2.18 643 0
6 Plum Creek Middle 2.0 2.18 269 0
7 Oneida Creek Unimpaired 2.1 1.24 2,925 0
8 Mud Creek Lower 2.0 0.66 579 219
9 Mud Creek Upper 2.0 0.66 67 26
10 Kankapot Creek Upper 2.1 1.85 5,569 0
11 Kankapot Creek Lower 2.1 1.85 102 0
12 City of Green Bay-Fox River
Below De Pere Dam
2.0 1.31
<10 <10
13 City of Green Bay-Fox River
Above De Pere Dam
2.0 1.31
2,004 13
14 Garners Creek-Fox River
Fox-below Middle-Appleton
Dam
2.0 1.19 854 111
15 Garners Creek-Fox River Garners Creek
2.0 1.19 886 123
16 Garners Creek-Fox River
Fox-above Middle-Appleton
Dam
2.0 1.19 <10 <10
49 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
17 Upper East River 2.3 2.11 7,160 0
18 Lower East River Upper 2.0 1.9 3,971 0
19 Lower East River Lower 2.0 1.9 896 0
20 Dutchman Creek Middle
Unimpaired 2.0 2.13
2,772 57
21 Dutchman Creek Lower 2.0 2.13 404 28
22 Dutchman Creek Upper 2.0 2.13 681 44
23 Upper Duck Creek Upper
Unimpaired 2.4 1.72
5,084 78
24 Upper Duck Creek Lower 2.4 1.72 2,640 <10
25 Middle Duck Creek
Lower Unimpaired 2.1
1.85 3,406 <10
26 Middle Duck Creek Upper 2.1
1.85 440 <10
27 Lower Duck Creek Lower 2.0 1.25 444 0
28 Dead Horse Bay-Frontal Green Bay 2.0
0.53 66 <10
29 Little Lake Butte des Mortes Fox River 2.0
1.16 557 50
30 Little Lake Butte des Mortes
Upper most Unimpaired 2.0
1.16 921 87
31 Little Lake Butte des Mortes Upper 2.0
1.16 1,015 96
32 Little Lake Butte des Mortes Middle 2.0
1.16 254 27
33 Little Lake Butte des Mortes Lower 2.0
1.16 166 15
34 Bower Creek Lower 2.0 1.81 3,414 0
35 Bower Creek Upper 2.0 1.81 4,368 0
36 Baird Creek Upper 2.0 2.08 3,292 0
37 Baird Creek Lower 2.0 2.08 0
38 Ashwaubenon Creek 2.0
1.86 4,566 142
50 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
39 Lower Duck Creek Upper Unimpaired 2.0
1.25 965 0
Table III-12. Potentially available interim and long-term TSS cropland credits (one credit offsets one ton of TSS/yr
discharged by the buyer). (A <10 value indicates the analysis projected less than 10 credits and therefore the introduction
of modeling uncertainty is too great to list the value itself.)
ID HUC 12 Name
40 Sub-HUC-12
Description
Trade
Ratio
Potential
Number of
Interim
Potential TSS
Credits
Potential
Number of
Long-term
Potential TSS
Credits
0 Apple Creek Upper 2.0 1,013 345
1 Apple Creek Lower 2.0 227 84
2 Trout Creek Unimpaired 2.1 118 95
3 Point du Sable-Frontal Green Bay 2.0 608 275
4 Plum Creek Lower 2.0 1,003 149
5 Plum Creek Upper 2.0 70 12
6 Plum Creek Middle 2.0 31 <10
7 Oneida Creek Un-impaired 2.1 585 198
8 Mud Creek Lower 2.0 137 112
9 Mud Creek Upper 2.0 16 13
10 Kankapot Creek Upper 2.1 593 132
11 Kankapot Creek Lower 2.1 11 <10
12 City of Green Bay-Fox River
Below De Pere Dam
2.0 <10 <10
13 City of Green Bay-Fox River
Above De Pere Dam
2.0 738 204
14 Garners Creek-Fox River
Fox-below Middle-Appleton Dam
2.0 83 47
15 Garners Creek-Fox River Garners Creek
2.0 83 48
16 Garners Creek-Fox River
Fox-above Middle-Appleton Dam
2.0 <10 <10
51 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
17 Upper East River 2.3 921 175
18 Lower East River Upper 2.0 497 98
19 Lower East River Lower 2.0 109 22
20 Dutchman Creek Middle un-impaired 2.0 478 263
21 Dutchman Creek Lower 2.0 67 39
22 Dutchman Creek Upper 2.0 115 66
23 Upper Duck Creek Upper Unimpaired 2.4 932 298
24 Upper Duck Creek Lower 2.4 493 155
25 Middle Duck Creek Lower Unimpaired 2.1 636 199
26 Middle Duck Creek Upper 2.1 83 27
27 Lower Duck Creek Lower 2.0 90 32
28 Dead Horse Bay-Frontal Green Bay 2.0 13 <10
29 Little Lake Butte des Mortes Fox River 2.0 117 54
30 Little Lake Butte des Mortes
Upper most Unimpaired 2.0 190 88
31 Little Lake Butte des Mortes Upper 2.0 215 100
32 Little Lake Butte des Mortes Middle 2.0 52 24
33 Little Lake Butte des Mortes Lower 2.0 35 16
34 Bower Creek Lower 2.0 348 76
35 Bower Creek Upper 2.0 449 97
36 Baird Creek Upper 2.0 418 251
37 Baird Creek Lower 2.0 <10 <10
38 Ashwaubenon Creek 2.0 799 403
39 Lower Duck Creek Upper Unimpaired 2.0 177 56
52 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Credit Price Point Determination
The credit price points for rural nonpoint source credits were estimated using a process similar to
the WWTF demand evaluation’s willingness to pay based on high, medium and low price point
ranges. As such, potential credits were sorted into similar price point ranges. This method
facilitated an easier comparison of the demand for credits at a given cost with the credits
available that provided an economic benefit. As such, the rural phosphorus and sediment
reduction costs were transformed into an annualized unit cost format (i.e., $/lbs TP/yr and $/ton
TSS/yr). The same life-cycle cost assumptions used in the demand analysis were applied (i.e.,
conversion to 20-year project life, a 3.3 % inflation rate, a 6% nominal discount factor). In
addition, credit price points included the consideration of a 10% transaction fee and the trade
ratio application (which translates predicted reductions into credits).
Table III-13 presents the credit supply generation price point ranges for phosphorus and Table
III-14 presents the credit supply price point ranges for TSS.
Table III-13. High, medium and low credit price point ranges for Ag and rural phosphorus credit generation capabilities.
Credit Price Point Range (&
Credit Generation Source)
Rural TP Credit Generation Price Point Ranges at a
2 : 1 Trade Ratio
(assumes full cost of practices is compensated)
($/TP Credit)
Low (Cropland Rotations 3, 6, 7 &
Gully protection1)
$14 to $95
Medium (Cropland Rotations 11, 2
& Streambank protection) $101 to $188
High (Cropland Rotations 4 & 51) $200 to $233
AFOs (extremely high)2 $7,900
1Lowest BMP system price point in range.
2AFO average annualized unit costs are typically above WPDES demand costs and therefore are not used in the low, medium and
high ranges as they would mask the cost of other credits generated by cropland practices
Table III-14. High, medium and low credit price point ranges for Ag and rural TSS credit generation capabilities.
Credit Price Point Range
(& Credit Generation
Source)
Rural TSS Credit Generation Price Point Ranges at a
2 : 1 Trade Ratio
(assumes full cost of practices is compensated)
($/TSS Credit)
Low (Cropland Rotation 6 &
Gully protection1)
$14 to $151
Medium (Cropland Rotations 1, $188 to $539
53 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
3, 7 & Streambank Protection1)
High (Cropland Rotation 21, 4 &
5) $634 to $1546
AFOs estimates not available
1Lowest BMP system price point in range.
The capability to produce affordable credits is dictated by the willingness of the credit generator
to install the BMPs, the capability of the BMP system to reduce the water quality parameter of
interest, and the cost of the BMP system. Price points for phosphorus reductions in the LFRW
were high in these regards (i.e., one to three orders of magnitude) compared to other similar
programs generating nonpoint source credits. For instance, Fang (2005) estimated that Rahr
Malting Company in Minnesota was trading for phosphorus reductions at an estimated price of
$6.14 per unit. Likewise, the Great Miami River Water Quality Trading program has purchased
nitrogen and phosphorus credits for future trading at less than $2.00 per combined credit4. The
higher prices in the LFRW are potentially due to several factors that constrain the ability for
reductions within this watershed. The first factor relates to trading guidance and 2012 TMDL
requirements that reduce available credit supply with trade ratios and calibration of predicted
cumulative watershed loads to TMDL loads.
The second factor related to agricultural watershed characteristics. The watershed has a large
number of acres that are used to generate alfalfa. Alfalfa is a perennial crop that is not associated
with high erosion rates or large amounts of runoff. Another factor is the large percent of land
that has flat or gentle slopes. Low slopes are less erodible and sometimes can have low
connectivity regarding runoff. Finally, the dairy production demand for corn silage creates
challenges for inexpensive reductions on silage fields. Corn silage is a crop that needs most of
the growing season in northern latitudes of the Midwest. In addition, harvesting corn silage for
feedstock removes most of the plant material from the field. The practices that can protect water
quality in silage acres must work around the remaining short growing period left after harvest, or
be introduced before harvest or at the edge-of-field. These types of practices are typically more
expensive and some take land out of production.
The summary of the rural total TP credit supply by 40 sub-HUC-12 watersheds broken out by
cost ranges is provided in Tables III-15 and III-16 for interim and long-term credits, respectively.
The summary of the rural total TSS credit supply by 40 sub-HUC-12 watersheds broken out by
cost ranges is provided in Tables III-17 and III-18 for interim and long-term credits, respectively.
Of interest is the noticeable number of sub-HUC-12 watersheds that cannot produce long-term
TP credits, particularly in Table III-16.
4 Personal communication with Douglas “Dusty” Hall, former Miami Conservancy District Water Quality Credit
Trading Program Manager, October 2008.
54 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-15. Rural interim TP credit supply by price ranges for 2 to 1 trade ratios.
HUC 12 Name
Sub-
HUC-12
ID
Low Price
Range
(< $95)
Medium
Price Range
(<$188)
High Price
Range
(<$233) Total
Apple Creek 0 4,517 2,261 2,050 8,829
Apple Creek 1 1,386 576 298 2,259
Trout Creek 2 403 222 517 1,142
Point du Sable-Frontal Green Bay 3 2,190 346 636 3,172
Plum Creek 4 4,782 3,601 1,642 10,025
Plum Creek 5 423 70 176 669
Plum Creek 6 137 320 52 508
Oneida Creek 7 1,558 244 1,122 2,925
Mud Creek 8 155 22 403 579
Mud Creek 9 14 - 48 62
Kankapot Creek 10 3,236 1,337 1,578 6,151
Kankapot Creek 11 52 249 45 346
City of Green Bay-Fox River 12 - - - 0
City of Green Bay-Fox River 13 810 277 917 2,004
Garners Creek-Fox River 14 478 157 219 854
Garners Creek-Fox River 15 417 181 444 1,042
Garners Creek-Fox River 16 - - - 0
Upper East River 17 3,860 2,509 1,701 8,070
Lower East River 18 2,280 1,656 1,112 5,048
Lower East River 19 534 125 236 896
Dutchman Creek 20 1,864 470 438 2,772
55 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Dutchman Creek 21 268 47 88 404
Dutchman Creek 22 511 96 74 681
Upper Duck Creek 23 2,576 646 1,863 5,084
Upper Duck Creek 24 1,238 387 1,014 2,640
Middle Duck Creek 25 1,595 676 1,135 3,406
Middle Duck Creek 26 232 66 142 440
Lower Duck Creek 27 191 288 241 720
Dead Horse Bay-Frontal Green Bay 28 32 - 28 60
Little Lake Butte des Mortes 29 142 47 364 553
Little Lake Butte des Mortes 30 195 55 667 916
Little Lake Butte des Mortes 31 377 58 580 1,015
Little Lake Butte des Mortes 32 59 - 188 248
Little Lake Butte des Mortes 33 34 20 105 159
Bower Creek 34 1,709 938 1,048 3,695
Bower Creek 35 1,994 1,704 1,615 5,314
Baird Creek 36 1,904 645 743 3,292
Baird Creek 37 4 70 - 74
Ashwaubenon Creek 38 2,748 788 1,030 4,566
Lower Duck Creek 39 619 1,282 262 2,164
56 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-16. Rural long-term TP credit supply by price ranges for 2 to 1 trade ratios.
HUC 12 Name
Sub-HUC-
12 ID
Low
Price
Range
(< $95)
Medium
Price
Range
(<$188)
High Price
Range
(<$233) Total
Apple Creek 0 7 126 - 132
Apple Creek 1 56 85 11 152
Trout Creek 2 65 83 81 229
Point du Sable-Frontal Green Bay 3 438 69 127 635
Plum Creek 4 9 172 - 181
Plum Creek 5 0 3 - 4
Plum Creek 6 2 32 - 34
Oneida Creek 7 - - - -
Mud Creek 8 59 8 153 219
Mud Creek 9 5 - 19 24
Kankapot Creek 10 5 101 - 106
Kankapot Creek 11 2 43 - 45
City of Green Bay-Fox River 12 - - - -
City of Green Bay-Fox River 13 5 2 6 13
Garners Creek-Fox River 14 62 20 28 111
Garners Creek-Fox River 15 60 59 62 181
Garners Creek-Fox River 16 - - - -
Upper East River 17 7 139 - 147
Lower East River 18 9 165 - 173
Lower East River 19 - - - -
Dutchman Creek 20 38 10 9 57
57 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Dutchman Creek 21 19 3 6 28
Dutchman Creek 22 33 6 5 44
Upper Duck Creek 23 40 10 29 78
Upper Duck Creek 24 4 1 3 9
Middle Duck Creek 25 3 1 2 6
Middle Duck Creek 26 2 1 1 4
Lower Duck Creek 27 3 61 - 64
Dead Horse Bay-Frontal Green Bay 28 3 - 3 6
Little Lake Butte des Mortes 29 13 4 33 49
Little Lake Butte des Mortes 30 18 5 63 87
Little Lake Butte des Mortes 31 36 5 55 96
Little Lake Butte des Mortes 32 6 - 20 26
Little Lake Butte des Mortes 33 3 2 10 14
Bower Creek 34 2 45 - 47
Bower Creek 35 8 151 - 159
Baird Creek 36 - - - -
Baird Creek 37 1 14 - 15
Ashwaubenon Creek 38 85 25 32 142
Lower Duck Creek 39 14 263 - 277
58 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-17. Rural interim TSS credit supply by price ranges for 2 to 1 trade ratios.
HUC 12 Name
Sub-HUC-
12 ID
Low
Price
Range
(< $188)
Medium
Price
Range
(<$544)
High Price
Range
(<$1,563) Total
Apple Creek 0 180 1,711 360 2,252
Apple Creek 1 57 869 53 978
Trout Creek 2 21 371 70 462
Point du Sable-Frontal Green Bay 3 78 359 172 608
Plum Creek 4 261 3,002 331 3,594
Plum Creek 5 13 89 20 123
Plum Creek 6 25 472 14 510
Oneida Creek 7 32 297 257 585
Mud Creek 8 1 39 97 137
Mud Creek 9 0 4 12 16
Kankapot Creek 10 100 1,441 215 1,756
Kankapot Creek 11 25 476 5 506
City of Green Bay-Fox River 12 - 0 1 1
City of Green Bay-Fox River 13 78 283 377 738
Garners Creek-Fox River 14 10 41 32 83
Garners Creek-Fox River 15 17 334 42 394
Garners Creek-Fox River 16 - - 0 0
Upper East River 17 219 2,191 330 2,740
Lower East River 18 143 2,307 199 2,649
Lower East River 19 9 61 39 109
Dutchman Creek 20 69 285 124 478
59 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Dutchman Creek 21 2 46 20 67
Dutchman Creek 22 9 88 18 115
Upper Duck Creek 23 62 474 396 932
Upper Duck Creek 24 41 233 220 493
Middle Duck Creek 25 52 330 254 636
Middle Duck Creek 26 5 43 35 83
Lower Duck Creek 27 30 557 56 643
Dead Horse Bay-Frontal Green Bay 28 0 6 6 13
Little Lake Butte des Mortes 29 1 33 83 117
Little Lake Butte des Mortes 30 1 44 146 190
Little Lake Butte des Mortes 31 3 81 131 215
Little Lake Butte des Mortes 32 0 13 38 52
Little Lake Butte des Mortes 33 0 13 22 35
Bower Creek 34 60 700 150 910
Bower Creek 35 136 1,985 219 2,341
Baird Creek 36 43 235 140 418
Baird Creek 37 8 141 0 150
Ashwaubenon Creek 38 168 373 258 799
Lower Duck Creek 39 127 2,385 64 2,576
60 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table III-18. Rural long-term TSS credit supply by price ranges for 2 to 1 trade ratios.
HUC 12 Name
Sub-HUC-
12 ID
Low
Price
Range
(< $188)
Medium
Price
Range
(<$544)
High Price
Range
(<$1,563) Total
Apple Creek 0 67 698 123 888
Apple Creek 1 24 370 19 413
Trout Creek 2 18 323 56 397
Point du Sable-Frontal Green Bay 3 35 162 78 275
Plum Creek 4 52 706 49 807
Plum Creek 5 3 19 4 26
Plum Creek 6 6 118 2 126
Oneida Creek 7 11 100 87 198
Mud Creek 8 1 31 79 112
Mud Creek 9 0 3 10 13
Kankapot Creek 10 28 435 48 511
Kankapot Creek 11 8 155 1 164
City of Green Bay-Fox River 12 - - - -
City of Green Bay-Fox River 13 22 78 104 204
Garners Creek-Fox River 14 6 23 18 47
Garners Creek-Fox River 15 11 222 24 258
Garners Creek-Fox River 16 - - - -
Upper East River 17 51 596 63 710
Lower East River 18 39 653 39 730
Lower East River 19 2 12 8 22
Apple Creek 0 38 157 68 263
61 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Apple Creek 1 1 27 11 39
Trout Creek 2 5 51 10 66
Point du Sable-Frontal Green Bay 3 20 152 127 298
Plum Creek 4 13 73 69 155
Plum Creek 5 16 103 79 199
Plum Creek 6 1 14 11 27
Oneida Creek 7 12 229 20 261
Mud Creek 8 0 3 3 6
Mud Creek 9 0 15 39 54
Kankapot Creek 10 0 20 68 88
Kankapot Creek 11 1 38 61 100
City of Green Bay-Fox River 12 0 6 18 24
City of Green Bay-Fox River 13 0 6 10 16
Garners Creek-Fox River 14 16 211 33 260
Garners Creek-Fox River 15 40 628 47 715
Garners Creek-Fox River 16 26 141 84 251
Upper East River 17 6 98 0 104
Lower East River 18 85 188 130 403
Lower East River 19 52 977 20 1,049
WWTF Credit Supply
Credit supply potential from permitted WWTFs was initially intended to be part of the project
analysis. However, access to facility specific information was limited by time and resource
constraints at the offices where requests for information were submitted. Limitations on
available design data especially precluded the Project Team from forecasting the WWTFs’
ability to generate credits. Using the discharge and factsheet data that were provided to estimate
a facility’s ability to treat beyond what is required would have been too speculative to present.
62 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
At the WWTF in-person meeting, held on November 17, 2014 in Appleton, Wisconsin, one
representative indicated that their administration was currently evaluating their ability to
generate credits. This type of evaluation is strongly encouraged. Municipal and industrial
WWTFs may become an affordable source of TP credits. The treatment costs for WWTFs can
be substantially lower than the treatment costs associated with MS4 BMPs in some
circumstances. For instance, the medium cost range for WWTFs in Table II-5 is $42/lb TP
compared to the low range unit cost for MS4 facilities in Table 10 of $880/lb of TP. In addition,
the trade ratio applied to this type of credit generation could be as low as 1.2 to 1 for many
locations in the LFRW. Trades that use WWTF generation of TSS credits should also be
evaluated.
Considerations and Recommendations for Other Potential Credit Suppliers
Considerations and recommendations for other phosphorus and TSS source types capable of
producing credits were preliminarily developed. Other source types included regulated and
unregulated urban stormwater sources, channelized ephemeral flows during snow melt and large
storm events, wetland creation or restoration, and phosphorus reduction activities located in and
above the subwatersheds of Lake Winnebago. Many of these source types and BMP options
were considered by the Agricultural Oversight Committee to contribute or reduce sizeable
nonpoint source loads to the LFRW.
These sources are incorporated into the credit supply discussion to identify information gaps,
high-potential approaches to resolve the gaps, and appropriate modeling efforts to consider
regarding assessment of future credit generation.
Urban stormwater: To generate credits from urban stormwater sources, several issues must be
addressed. One involves establishing a credit generation threshold for unpermitted MS4s before
they are eligible to generate credits. A second issue is the need to develop an efficient means of
estimating discharged loading in comparison to the allocated loading in the 2012 TMDL. This
includes how future growth is managed. Finally, the WI DNR would need to approve methods
used to address these concerns as well as a credit estimation method.
Channelized ephemeral flow in fields: Spring time snow melt and large summer storm events
can create wide, shallow channelized flows across cropped fields. Producers that land apply
manure before snow melt or frost out conditions often are thought to place some of the
applications in these flow paths. The flows do not create gullies, but can create rills and carry
soluble nutrients off the field. The Agricultural Oversight Subcommittee recognized BMPs like
grassed waterways would address this source, although the current version of SnapPlus does not
estimate the nutrient reductions using this BMP. This type of BMP estimation could identify
additional interim credits (i.e., addressing channelized flow is required under N.R. 151). A WI
DNR approved credit estimation method is likely needed for this source to become creditable.
63 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Wetland creation or restoration: Wetlands are an appropriate BMP for some producers.
Producers who identify some of their cropland in operation as marginal may consider
implementing wetlands for hunting and other recreation purposes. This type of activity can be
considered as a replacement of infield BMPs if an approved credit estimation method determines
it is equivalent to treatment efficiencies for infield options.
Phosphorus reduction activities located in and above Lake Winnebago: The contributing
watershed to Lake Winnebago and the internal loading of nutrients contribute to the TP loading
in the LFRW. Loading reductions for these sources will improve the Lake’s quality and
potentially reduce the loading coming out of the Lake at the headwaters of the Lower Fox River.
The USGS is leading an assessment project determining the hydrology, water quality and
response to simulated changes in phosphorus loading of the Winnebago Pool Lakes. The
findings of this study should be of value to assist with the determination of the nutrient
attenuation characteristics of the system.
Nonpoint source loading from lands above Lake Winnebago, could have a wide variation of
delivery factor discounts depending on the flow regime and residence times in the Lake. A
better understanding of the nutrient cycle is strongly recommended before entertaining potential
credit opportunities from upland sources in the Upper Fox River watershed. Likewise,
understanding the internal nutrient dynamics is necessary to address credit supplies from
practices like lake bottom dredging and alum addition. These practices not only require an
approvable credit estimation method, but the wide range of potential variability in loading from
year-to-year necessitates that the method must be grounded on the lake hydrology and
associated nutrient cycling dynamics at different flow regimes.
64 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
IV. COMPARISON OF DEMAND AND SUPPLY
Comparison of WQT credit demand with supply fundamentally identifies the viability of a
LFRW trading program in the context of prevailing assumptions and constraints. Results of this
determination can be used to inform the ongoing development process of a LFRW trading
framework. The comparison evaluation here contains two distinct criteria that when achieved,
create the foundation for a robust WQT program. The first criterion is the ratio of credit supply
to demand. When programs have a ratio that is well balanced or reflects a relatively large
number of potential credit suppliers compared to demand, it is usually a strong indicator of the
potential for sizable participation in WQT as well as economic and environmental benefits.
The potential for large credit supply can ease some of the anxiety that buyers have when
engaging in a new market. One way such a supply assists market confidence is by increasing the
potential number of credit generators who are willing to participate in the market, potentially
controlling credit costs. In addition, large to moderate credit volumes allow buyers to evaluate if
compliance can be obtained solely by using trading, or by implementing a combination of
trading and an affordable upgrade. If, however, sufficient long-term credits are not available to
provide for a relatively low risk use of a combined upgrade and trading, then trading may not be
attractive and/or be quite limiting for buying seeking trading relief for longer compliance
schedules. Though the results of this study were not able to obtain individual facility planning
and intentions, they can inform entities of potential trading options as they enter their own
planning process. To summarize, the first criterion for how the supply to demand ratio can be
used, the weaker the supply to demand is, the higher the likelihood that WQT will not be
perceived as beneficial by buyers.
The second criterion evaluates the cost differentials that exist between credit price points and the
buyer upgrade unit cost. This criterion informs the buyers regarding the potential cost savings
available with trading. If a cost-effective margin is not evident, then the ability to trade water
quality credits will be limited or perhaps might not exist. If there is a small cost margin between
a credit supplier’s price point and the buyer’s facility upgrade unit cost, the benefits of a full
upgrade are likely to look more favorable. Unfavorable cost margins defined in this study were
determined by assuming a cost savings of less than 25 percent of the upgrade unit cost would not
attractive to buyers.
Comparison of Demand and Supply Method
Project Team assessment of the first criterion for supply and demand comparisons involved the
following steps:
Review of supply and demand comparison methodologies
Comparison of total supply and demand
Mapping demand and supply in the LFRW
65 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Review of Supply and Demand Methods
The initial effort in this portion of the evaluation was to compare the credit supply directly with
the amount of reduction required by the 2012 TMDL for WWTFs and MS4s. The second step in
the evaluation involved Project Team discussions with the PMT to gather their input regarding
the assumptions and methods being proposed for this comparison. A conference call was held to
review the approach for these efforts. The PMT agreed to a method that compared available
credit supply to the WWTF and MS4 demand by using a range of low, medium, and high
annualized unit costs. The annualized unit costs were established based on the life-cycle cost
analysis explained in Section II of this report. The same life-cycle cost assumptions were used
for all unit cost estimates for credits (i.e., conversion to 20-year project life, a 3.3 percent
inflation rate, and a 6 percent nominal discount factor). In addition, total credit costs included
the consideration of a 10% transaction fee and the trade ratio. Finally, the volume of credit
supply was grouped into three credit price points and compared with the WWTF upgrade and
MS4 implementation unit cost ranges of high, medium and low.
Credit Supply Volume and Demand Comparison
The list of potential buyers consisted of 10 WWTFs facing upgrade costs and the complete list of
25 permitted MS4 entities facing at least a 30 percent reduction requirement for TP and TSS
reduction requirements ranging from 28.5 to 65.2 percent. Associated TP and TSS demand for
these entities basin-wide versus interim and long-term credit supply for both TP and TSS is
provided in Table IV-1.
Table IV-1. Annual LFRW basin-wide credit demand (reductions) and rural credit supply estimates.
Basin Wide Comparison of Annual Demand and Supply
Buyer TP Reduction (lbs TP) TSS Reduction (tons TSS)
All Identified
WWTFs 144,399 --1
Ten Facilities Identified with Short Term Reduction
Potential Demand
68,656
--1
MS4s 32,805 10,960
Credit
Supplier
Potential
For Interim
TP Credits
Potential for
Long-term TP
Credits
Potential For
Interim TSS
Credits
Potential For
Long-term TSS
Credits
Cropland 84,306 1,996 12,555 4,265
66 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Streambank &
Gully 5,519 1,599 16,949 6,013
AFO 5,876 1,424 -- --
1To be determined by the WWTF
Table IV-1 results indicate ample short-term (interim) TP credit supply for WWTFs, however,
shortages for long-term TP credits. Similar TP supply conditions are evident for MS4s, while
TSS may be the most robust trading opportunity between MS4s and rural nonpoint sources.
Trading program managers can use this comparative information to broadly inform policies. For
instance, this basin-wide comparison table could be used to assist those WWTFs with the
greatest financial compliance hardship. This might invoke trading framework considerations that
restrict trading to conditions that combine trading with mandatory yet affordable upgrades and/or
require that upgrades be prioritized above trading whenever the costs are economically
achievable.
Though informative, this basin summary certainly does not illustrate the comparison of credit
availability for buyers by sub-HUC-12 watersheds. Table IV-2 thus illustrates results for two
subwatersheds that are restricted by 303(d) listings for phosphorus. These have substantially
more reduction requirements for MS4s than there are long-term credits because of restrictions
with point of water quality standards applications. In this table, the MS4 entities discharging to
either impaired waterbody (Ashwaubenon Creek or Mud Creek) have substantially limited credit
supply to meet the 2012 TMDL load reduction goals through WQT (though fully offsetting all
MS4 stormwater reductions with rural credits is not being suggested here). Figure IV-1a and IV-
1b for Appleton and De Pere MS4 footprints, illustrate both how City stormwater discharges into
receiving waters and the eligible credit generating watersheds for those discharges.
Table IV-2. Mud Creek and Ashwaubenon Creek MS4 buyer reduction requirements compared to rural long-term credit
generation potential.
Creek
Long-term TP
Credit Supply
Estimate
(lbs/yr) City
Estimated Loading
Reduction
Requirement
(lbs TP/yr)
Ashwaubenon Creek
142
Ashwaubenon 157
De Pere 414
Hobart 292
Total 863
Creek Long-term TP
City Estimated Loading
67 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Credit Supply
Estimate
(lbs/yr)
Reduction
Requirement
(lbs TP/yr)
Mud Creek
243
Appleton 288
Grand Chute 1,696
Greenville 696
T. Menasha 368
Total 3,048
For identified WWTFs potentially seeking WQT opportunities, there are also sizeable
differences in terms of eligible credit generation areas particularly in the upper watershed. The
use of upstream credit generation as well as point of water quality standards applications under
the 2012 TMDL did reduce some of the supply to demand imbalance for these as depicted by
comparing Figures IV-2a and b, and IV-3. WWTFs located further downstream may have
substantially more eligible credit generation area available to them for supply.
68 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Figure IV-1a-b. a) Appleton and b) De Pere MS4 footprint and eligible subwatershed boundaries (shaded areas in gray are ineligible for generating credits for these
buyers).
69 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Figure IV-2a-b. WWTF entities located upstream of a) Middle Appleton Dam and b) between Middle Appleton Dam and De Pere Dam who might potentially benefit
from TP WQT for permit compliance at current day loadings (shaded areas in gray are ineligible for credit generation for these WWTFs).
70 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Figure IV-3. LFRW mainstem WWTF dischargers and their eligible TP credit generating subwatersheds (shaded areas
in gray are ineligible for credit generation for these WWTFs).
The economic comparison between TP sources of supply and demand using annualized unit
costs is provided in Table IV-3. This table also provides an economic comparison between TSS
sources of supply and demand using annualized unit costs. The economic comparison
emphasizes the likelihood of combining reasonable cost upgrades and trading solutions. One
recommendation that stems from these results is for facilities facing the highest cost range for
upgrades (where trading has a favorable cost margin compared to facility upgrades) to
implement affordable upgrade options and then pursue trading to meet their remaining
compliance/load reduction needs.
71 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table IV-3. Economic cost comparisons of buyer willingness to pay and credit price points for TP.
Source
Type
Willingness to Pay
Range
Rural Credit Supply Cost
Range
Economically
Viable
WW
TF
s (
Dem
an
d)
Low ($32)
Low ($14 to $95) Gullies @ $14
Medium ($101 to $188) No
High ($200 to $233) No
Medium ($68)
Low ($14 to $95) Yes
Medium ($101 to $188) No
High ($200 to $233) No
High ($300)
Low ($14 to $95) Yes
Medium ($101 to $188) Yes
High ($200 to $233) Yes
MS
4s
Low ($880)
Low ($14 to $95) Yes
Medium ($101 to $188) Yes
High ($200 to $233) Yes
Medium ($2,400)
Low ($14 to $95) Yes
Medium ($101 to $188) Yes
High ($200 to $233) Yes
High ($3,480)
Low ($14 to $95) Yes
Medium ($101 to $188) Yes
High ($200 to $233) Yes
72 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
1 Annualized cost methods based on current dollar life-cycle cost analysis using a 20-year life of project, 3.30
percent inflation rate and a 6 percent nominal discount factor. The total cost includes siting BMP locations, design,
capitalization, and annual operation and maintenance.
As indicated by Table IV-2 in some Sub-HUC-12 watershed areas there will not be credit
supplies available from phosphorus credit generating sources. Combining the cost margin
assessment with the potential volume of credits available actually limits the viability of trading
for certain subwatersheds even further. Thus, to inform decision-makers in this regard, a series
of tables have been created that cross reference the WWTF and MS4 reduction requirements
with eligible 40 sub-HUC-12 watershed credit potential by cost ranges of high, medium and low.
These tables exist in the separately provided MS ExcelTM
work book entitled: Interim and Long-
term Credit Supply and Demand Comparisons.
Because these comparisons are made at the watershed scale context and do not reflect site-
specific information for any one particular buyer or seller, results presented here must be viewed
as just that, a watershed-scale assessment of economic feasibility. In reality the actual demand
for credits will be influenced by several factors that can only be identified by the buyer. Supply
will be dictated by site-specific opportunities and rural land owner willingness to implement new
conservation practices.
Depending on how a water quality market is ultimately structured, this study reveals the
ramifications of trading considerations and implications on pricing in a market setting with
potentially limited supply. In an auction-based trading market with limited supply, bidding will
likely result in escalation of credit prices. Similarly, early investment in the most cost-effective
credits will lead to higher credit prices later as others enter the market late. WQT program
designers may therefore wish to consider equity policies in such a tight TP credit supply market.
This may not be as necessary for TSS as credit supply and demand ratios are better balanced in
terms of ability to supply the demand for reductions at substantial cost-savings.
73 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
V. CONCLUSIONS & RECOMMENDATIONS
The Project Team worked with the GLC, PMT and the Agricultural Oversight Subcommittee to
develop a WQT economic feasibility assessment in the LFRW that examined the ability for rural
credit supply to meet the potential demand from WWTFs and MS4s driven by the 2012 TMDL.
WI DNR (2013a) trading guidance was used to establish assumptions for assessing availability
and use of credits. One exception to this guidance was the WI DNR recommended use of a
water quality point of standards application for delineating 303(d) listed waters, and approved
TMDL eligible credit generation areas. The use of these particular applications removed the
need to apply additional credit discounts for downstream trading factors in the trade ratio
development step of the analysis.
The overall assessment relied heavily on methods that assumed generalized watershed conditions
and/or extrapolations from select watershed examples with local data. Thus, there was
substantial averaging used to create the estimates of demand, supply and associated costs.
Extensive interaction with the Agricultural Oversight Subcommittee did, however, provide
detailed and highly applicable assumptions for analysis of rural nonpoint source credit supply.
Limited available information for WWTFs and MS4s diminished opportunities for determining
more finite buyer-specific needs, though the use of standard engineering assumptions reduced
uncertainty and should in turn, bolster general confidence in demand estimates and costs. Given
this backdrop, this Economic Feasibility Study of WQT in the LFRW provides reasonable
estimates of cost and quantity of load reductions and credits.
The economic feasibility evaluation for WWTF and MS4 permitted entities to cost-effectively
achieve compliance for TP and TSS through trading was based on three elements. The first was
assessment of TP load reduction needs from current discharges to meet anticipated WQBELs for
TP under the 2012 TMDL. This also included application of a willingness to pay threshold for
buyers that was represented by a range of low, medium and high price points for credit costs.
The second element was estimation of trading supply and related costs for credits generated by
rural nonpoint sources of TP and TSS associated with croplands, AFOs and streambank
erosion/riparian gully erosion. The potential for credit generation from rural sources was also
separated into three credit price points of low, medium and high for comparison with the
potential buyer costs. The third element was comparison of willingness to pay values
determined in the first element with the credit price points developed in the second element.
This economic feasibility analysis identified strong potential for a robust MS4 TSS-based trading
program as reduction requirement compliance schedules draw near for communities under the
2012 TMDL. The potential for TP trading that would benefit municipal and industrial WWTFs
and MS4 communities was identified, though likely at a more limited scale than TSS trading. TP
credits were identified as cost-effective for interim 5-year credits at medium and high price
74 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
points for WWTF upgrades. However, the ability for rural nonpoint sources to generate
sufficient long-term TP credits to fulfill future demand was a deeply constraining factor.
Issues constraining long-term TP credit generation included reduction requirements placed on
rural sources in the 2012 TMDL, and WQT program guidance that defined eligible watersheds
for credit generation. The first issue here could be managed in an approach that minimizes the
impact of limited supply. Should a WQT program advance, it might consider efficient targeting
of credit generation sites while emphasizing that buyers must potentially implement a level of
onsite phosphorus controls before being eligible to participate in trading. In addition, sequencing
compliance schedules among permitted facilities in a manner that allows for multiple entities to
use the same credit generating sites at different time periods might bolster effective use of
available credits.
The second constraining issue, WQT program requirements that define eligible watersheds for
credit generation, should likely not be altered. The use of WQT must comply with permit
requirements where discharges cannot cause or contribute to water quality standards violations.
Until crediting issues identified in 303(d) listed impaired waters and approved TMDLs have
been fully addressed, these restrictions should remain in place.
To successfully manage a water quality trading program in this limited TP credit supply setting
as observed in this study, the Project Team offers the following.
General Considerations/Recommendations
Estimates of costs, supply and demand are intended to inform facility representatives and
watershed managers of the basin-wide potential for viable water quality trading given availability
of credits in watersheds eligible for credit generation specific to their facility. Actual ranges of
WWTF and MS4 treatment costs are expected to vary for those facilities facing new TP
compliance requirements for their effluent. It is recommended that responsible entities assess
their own individual circumstances based on their facility understanding before relying on
generalizations in this study. WWTFs that are capable of treating beyond their requirements
should consider generating credits for point source to point source trading.
Not all producers and rural landowners will likely participate in WQT, thus the potential credit
estimates reported herein may be higher that actually available. Local professionals such as
technicians working in the County Land Conservation Departments will be able to better forecast
potential participation than could be assumed in this study’s credit supply analysis.
Future growth was not assessed as part of this study. Loading associated with growth should be
addressed by requiring minimum stormwater BMPs for new development, and possibly
including WQT options in order to achieve and maintain TMDL allocations.
75 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Recommendations for Credit Calculation Methods
Standardized estimation methods like the SnapPlus v.2 model are extremely valuable given its
site-specific accuracy and application to many types of agricultural settings. More credits could
potentially be recognized if upgrades to SnapPlus would allow computations for:
Improved predictions for loading on croplands that have subsurface tiling
Predictions of TSS loading using the embedded RUSLE2 model with edge-of-field
delivery factors
Prediction of manure related loadings from concentrated flow channels that exist in the
field when winter surface applied manure exists in these flow paths
The operation of SnapPlus requires a special skill set for users that should be expanded through
training investments in competent operators within the watershed.
Watershed and trading program managers should consider and/or invest in credit computation
methods for new technology alternatives that remove phosphorus from the watershed. Examples
of such source reductions could come from:
Manure, using manure digesters to increase cost efficiencies associated with hauling
manure greater distances for land applications
Ephemeral channelized flow path management for land application of manure
Watershed and trading program managers should expand the list of approved trading credit
estimation methods to include other BMPs such as, but not limited to wetlands creation and
streambank erosion.
Stakeholder Identified Barriers and Benefits with WQT
Watershed and WQT program managers should continue to invest in education and information
on water quality protection needs and options through WQT. It was expressed by multiple
agricultural professionals that attitudes towards participation in WQT will improve over time as
the novelty of WQT wears off and it becomes more widely used.
Watershed management in areas with high soil test phosphorus results is a concern for
agricultural settings with high livestock densities. Careful and balanced considerations are
necessary in order to maintain the economic health of agriculture in the region while protecting
water quality. Currently the perception of experts is that high phosphorus soil content is an
outcome of the density of livestock compared to the available fields for land application of the
manure. Alternative manure management technologies are emerging. Therefore, this concern
can likely be addressed over time.
76 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Watershed characteristics of the LFRW basin create difficulties when delineating subwatershed
boundaries. Many different watershed delineations have originated from various watershed-
focused agencies or organizations. Watershed program management and future WQT credit
generation protocols would benefit from an approved and broadly adopted watershed delineation
map for the LFRW.
The 2012 TMDL contains substantial TP percent reduction requirements. As such, trading
program applications would benefit from TMDL compliance schedules for allocated sources.
Schedules can be structured to maximize the use of credit generation sites by multiple entities
over time if buyers have varied compliance schedules. Timelines for achieving phosphorus
reductions could be scheduled to allow both intentional sequencing of upgrades and stormwater
implementation schedules in a manner that maximize credit availability for credit buyers.
Ultimately, this should result in earlier and more cost-effective reductions.
The 2012 TMDL load allocation includes numerous rural sources of TP and TSS. A WI DNR
approved sub-delineation of the “Agricultural” load allocation could help to identify other credit
generation source types like livestock exclusion from streams.
And finally, clear and transparent tracking of decisions on WQT guidance applications and
interpretations will help to reduce market uncertainty for trading participants.
77 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
WORKS CITED
Fang, F., K.W. Easter and P.L. Brezonik (2005) Point-Nonpoint Source Water Quality Trading:
A Case Study in the Minnesota River Basin. Journal of the American Water Resources
Association 41(3):645-658.
Geosyntec Consultants, Inc. and Wright Water Engineers, Inc. International Stormwater Best
Management Practices (BMP) Database Pollutant Category Summary: Statistical
Addendum. July 2012. Available online at:
http://www.bmpdatabase.org/Docs/2012%20Water%20Quality%20Analysis%20Addend
um/BMP%20Database%20Categorical_SummaryAddendumReport_Final.pdf
USDA National Agricultural Statistics Service. 2013 Wisconsin Agricultural Statistics. October
2013. Available online at:
http://www.nass.usda.gov/Statistics_by_State/Wisconsin/Publications/Annual_Statistical
_Bulletin/bulletin2013_web.pdf
U.S. DOE (1995) NIST Handbook 135. Life-cycle Costing Manual for the Energy Management
Program. 1995. Available online at: http://fire.nist.gov/bfrlpubs/build96/PDF/b96121.pdf
US EPA (2003) Final Water Quality Trading Policy. Office of Water. January 13, 2003.
Available online at: http://water.epa.gov/type/watersheds/trading/finalpolicy2003.cfm
Wisconsin DNR (2012) Total Maximum Daily Load and Watershed Management Plan for Total
Phosphorus and Total Suspended Solids in the Lower Fox River Basin and Lower Green
Bay. March 2012.
Wisconsin DNR (2013a) A Water Quality Trading How To Manual. Guidance Number: 3400-
2013-03. September 9, 2013.
Wisconsin DNR (2013b) Guidance for Implementing Water Quality Trading in Permits.
Guidance Number: 3400- 2013-04. August 21, 2013.
Wisconsin DNR (2013c) TMDL Development and Implementation Guidance: Integrating the
WPDES and Impaired Waters Program, Edition No. 2. Guidance Number: 3400-2013-02.
April 15, 2013.
XCG (2010) Review of Phosphorus Removal at Municipal Sewage Treatment Plants
Discharging to the Lake Simcoe Watershed.
78 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
APPENDIX A Permitted Wastewater Treatment Facility Cost Estimation Methods
79 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Wastewater Treatment Facility Cost Estimation Methods
In the analysis for the Lake Simcoe Watershed conducted by XCG in 2010, incremental capital
costs were developed for the conceptual level WWTF upgrades required to achieve annual
effluent objective TP concentrations of 0.10 mg/L and 0.05 mg/L. These performance targets
were based on the findings in Ross et al. (1994), which found that effluent TP concentrations of
less than 0.10 mg/L are achievable on a continuous basis using tertiary filtration.
The incremental capital costs developed for the addition of granular media filters were based on
actual costs for upgrades to other facilities over a range of flows, and included allowances only
for the following:
Filter mechanism and media;
Filter building construction/expansion;
Process piping modifications;
Yard piping; and,
Electrical / SCADA modifications and upgrades.
An allowance of 40 percent was included to cover costs associated with engineering,
mobilization, demobilization, contractor overhead, and other miscellaneous construction costs.
All costs presented were strictly the incremental costs associated with wastewater treatment
facility (WWTF) upgrades for phosphorus removal. No capital costs were included for the
upgrade or expansion of any other treatment process at the WWTF to handle flows beyond the
current rated capacity of the works. Costs did not consider site specific factors such as the need
to acquire additional land, site conditions (including geotechnical conditions and/or intermediate
pumping requirements) or the assimilative capacity of the receiving stream.
Information regarding site specific details of the WWTFs discharging to the Lower Fox River
Basin, including facility components and configuration, historic unit process performance and
operating conditions, and site conditions were limited at the time of writing of this report.
Therefore, in order to develop conceptual level incremental costs to upgrade these facilities to
include tertiary granular media filtration, a cost curve was generated based on the conceptual
level upgrades to tertiary granular media filtration that were developed for the Lake Simcoe
Study (XCG, 2010). This cost curve, in conjunction with the historic flows to each WWTF, was
used to estimate the incremental capital cost associated with upgrading the WWTFs in the short
term, to include tertiary granular media filtration at historic flows.
The following notes apply to the cost estimates:
The incremental capital costs developed for the addition of granular media filters at
historic flows included the same allowances as included in the Lake Simcoe capital cost
estimates.
The incremental costs were developed for facilities currently not achieving WQBELs,
and were based on historic flows rather than on the design capacity of the WWTF in
80 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
order to determine the immediate capital costs to reduce effluent TP loading in the near
term.
Peak flows used for sizing tertiary filters were estimated by developing an assumed
service population at the historic mean daily flows based on a per capita flow of 455
L/cap/d (120 gal/cap/d) including an allowance for Infiltration/Inflow. This population
was then used to calculate a Harmon peaking factor which was applied to the capacity, to
estimate the peak flow requirements. The actual required design peak flow of the facility
may differ from this value, impacting the sizing and cost of tertiary treatment.
All costs are presented in 2014 US dollars (USD).
All costs are conceptual level opinions of probable costs only, and were developed for the
purposes of comparison of costs for TP loading reduction alternatives in the Lower Fox
River Basin.
All costs presented are strictly the incremental costs associated with WWTF upgrades for
phosphorus removal.
The incremental costs do not include any costs for the upgrade or expansion of any other
treatment process at the WWTF.
Site specific constraints such as land availability, site conditions or assimilative capacity
of the receiving stream were not considered in the development of the conceptual level
upgrades.
APPENDIX A WORKS CITED
Ross, D., S.G. Nutt, K. Murphy, and D. Averill (1994). Evaluation of Cost-Effective Treatment
Processes to Achieve Phosphorus Levels Less than 0.10 mg/L in Municipal WWTP
Effluent. Proc. of the Water Environment Federation, WEFTEC 1994, pp. 37-48.
81 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
APPENDIX B
Permitted MS4 Demand Tables
82 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 1-B. MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements
MS4 Watershed Location TP Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Allouez East River (Lower) 1,267 30.0% 380
Allouez Lower segment -- Fox
River 827 30.0% 248 Appleton Apple Creek (Upper) 2,616 30.0% 785 Appleton Garners Creek 1,060 63.1% 669 Appleton Mud Creek (Lower) 738 39.0% 288
Appleton Upper Duck Creek
(impaired) 230 30.0% 69
Appleton Fox River Lake Winn. to
Middle Appleton Dam 1,229 30.0% 369 Appleton middle-stem Fox River 3,954 30.0% 1,186 Ashwaubenon Ashwaubenon Creek 524 30.0% 157
Ashwaubenon Dutchman Creek (2
segments) 3,734 30.0% 1,120 Ashwaubenon Duck Creek (Lower) 207 30.0% 62
Ashwaubenon lower segment -- Fox
River 762 30.0% 229 Bellevue East River (Lower) 1,956 30.0% 587 Bellevue Baird Creek (Upper) 50 30.0% 15 Bellevue Bower Creek (Upper) 315 30.0% 95 Bellevue Bower Creek (Lower) 2,318 30.0% 695 Buchanan Plum Creek (Lower) 2.0 30.0% 0.6 Buchanan Kankapot Creek (Upper) 3.6 30.0% 1.1 Buchanan Garners Creek 1,566 63.1% 988 Buchanan middle-stem Fox River 126 30.0% 38 Combined
Locks Kankapot Creek (Lower) 4.9 30.0% 1.5 Combined
Locks Garners Creek 547 63.1% 345 Combined
Locks middle-stem Fox River 296 30.0% 89
De Pere East River (Lower) 799 30.0% 240 De Pere East River (Upper) 186 30.0% 56 De Pere Ashwaubenon Creek 1,380 30.0% 414 De Pere middle-stem Fox 1,887 30.0% 566 De Pere lower segment -- Fox 733 30.0% 220
83 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 1-B (continued). MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements (continued)
MS4 Watershed Location TP Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Grand Chute Apple Creek (Upper) 514 30.0% 154 Grand Chute Mud Creek (Upper) 235 39.0% 92 Grand Chute Mud Creek (Lower) 4,113 39.0% 1,604
Grand Chute Fox River Lake Winn. to
Middle Appleton Dam 77 30.0% 23 Green Bay East River (Lower) 2,368 30.0% 710 Green Bay Baird Creek (Upper) 2,268 30.0% 680 Green Bay Baird Creek (Lower) 2,261 30.0% 678 Green Bay Bower Creek (Lower) 138 30.0% 41 Green Bay Dutchman Creek (Lower) 700 30.0% 210
Green Bay Lower Duck Creek
(Lower) 1,611 30.0% 483
Green Bay Lower Duck Creek
(Upper unimpaired) 1,002 30.0% 301
Green Bay Lower Green Bay (Pt du
Sable) 4,764 30.0% 1,429 Green Bay lower segment -- Fox 3,881 30.0% 1,164 Greenville Mud Creek (Upper) 452 39.0% 176 Greenville Mud Creek (Lower) 1,191 39.0% 464 Harrison Garners Creek 1,276 63.1% 805 Harrison middle-stem Fox ** See below Hobart Ashwaubenon Creek 972 30.0% 292
Hobart Dutchman Creek (Mid
un-impaired) 3,183 30.0% 955 Hobart Dutchman Creek (Lower) 1,170 30.0% 351
Hobart Lower Duck Creek
(Upper unimpaired) 3,051 30.0% 915
Hobart Lower Duck Creek
(Lower) 873 30.0% 262
Hobart Trout Creek (unimpaired) 1,984 30.0% 595
Howard Lower Duck Creek
(Upper unimpaired) 12 30.0% 4
Howard Lower Duck Creek
(Lower) 5,605 30.0% 1,682
Howard Trout Creek 133 30.0% 40
Howard Lower Green Bay (Dead
Horse Bay) 899 30.0% 270
Howard lower segment -- Fox
River
84 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 1-B (continued). MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements (continued)
MS4 Watershed Location TP Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Kaukauna Apple Creek (Upper) 694 30.0% 208 Kaukauna Plum Creek (Lower) 49 30.0% 15 Kaukauna Kankapot Creek (Lower) 1,060 30.0% 318 Kaukauna # Kankapot Creek Upper 39 30.0% 12 Kaukauna Garners Creek 150 63.1% 95 Kaukauna middle-stem Fox River 1,624 30.0% 487 Kimberly Garners Creek 166 63.1% 105 Kimberly middle-stem Fox River 880 30.0% 264 Lawrence Apple Creek 85 30.0% 26 Lawrence Ashwaubenon Creek 896 30.0% 269 Lawrence Dutchman Creek (Lower) 278 30.0% 83 Lawrence middle-stem Fox River 38 30.0% 11
Ledgeview Lower East River
(Lower) 72 30.0% 22 Ledgeview Bower Creek (Lower) 338 30.0% 101 Ledgeview middle-stem Fox River 192 30.0% 58 Little Chute Apple Creek (Upper) 1,382 30.0% 415 Little Chute middle-stem Fox River 956 30.0% 287
Menasha Fox River Lake Winn. to
Middle Appleton Dam 2,477 30.0% 743
Neenah Neenah Slough (Upper) 481 30.0% 144 Neenah Neenah Slough (Middle) 358 30.0% 107 Neenah Neenah Slough (Lower) 1,491 30.0% 447
Neenah Fox River Lake Winn. to
Middle Appleton Dam 588 30.0% 176 Scott Lower Green Bay 683 30.0% 205 Suamico Duck Creek 832 30.0% 250 Suamico Lower Green Bay 4,110 30.0% 1,233 T. Menasha Mud Creek 942 39.0% 368
T. Menasha main-stem Winn-M Appl
Dam 4,053 30.0% 1,216
85 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 1-B (continued). MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements (continued)
MS4 Watershed Location TP Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr)
T. Neenah Fox River Lake Winn. to
Middle Appleton Dam 628 30.0% 188 T. Neenah Neenah Slough (Upper) 930 30.0% 279 T. Neenah Neenah Slough (Middle) 206 30.0% 62 T. Neenah Neenah Slough (Lower) 529 30.0% 159 UWGB Lower Green Bay 534 30.0% 160
Table 2-B. MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements
MS4 Watershed Location TSS Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Allouez East River (Lower) 572,938 40.0% 229,175
Allouez lower segment -- Fox
River 480,553 65.2% 313,321
Appleton Apple Creek (Upper) 1,043,338 40.0% 417,335 Appleton Garners Creek 467,433 49.9% 233,249 Appleton Mud Creek (Lower) 347,760 28.5% 99,112
Appleton Upper Duck Creek
(impaired) 87,371 40.0% 34,948
Appleton Fox River Lake Winn. to
Middle Appleton Dam 713,701 65.2% 465,333 Appleton middle-stem Fox 2,296,842 65.2% 1,497,541 Ashwaubenon Ashwaubenon Creek 190,079 40.0% 76,032
Ashwaubenon Dutchman Creek
(2 segments) 1,586,948 40.0% 634,779 Ashwaubenon Duck Creek (Lower) 78,623 40.0% 31,449
Ashwaubenon lower segment -- Fox
River 442,465 65.2% 288,487 Bellevue East River (Lower) 884,182 40.0% 353,673 Bellevue Baird Creek (Upper) 22,582 40.0% 9,033 Bellevue Bower Creek (Upper) 107,694 40.0% 43,077 Bellevue Bower Creek (Lower) 792,831 40.0% 317,133
86 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 2-B (continued). MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements (continued)
MS4 Watershed Location TSS Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Buchanan Plum Creek (Lower) 647 40.0% 259 Buchanan Kankapot Creek (Upper) 1,808 40.0% 723 Buchanan Garners Creek 690,777 49.9% 344,698 Buchanan middle-stem Fox River 73,198 65.2% 47,725 Combined
Locks Kankapot Creek (Lower) 2,453 40.0% 981 Combined
Locks Garners Creek 241,074 49.9% 120,296 Combined
Locks middle-stem Fox River 171,714 65.2% 111,958 DePere East River (Lower) 361,143 40.0% 144,457 DePere East River (Upper) 84,135 40.0% 33,654 DePere Ashwaubenon Creek 483,725 40.0% 193,490 DePere middle-stem Fox River 1,096,147 65.2% 714,688
DePere lower segment -- Fox
River 425,971 65.2% 277,733
Grand Chute Apple Creek (Upper) 204,837 40.0% 81,935 Grand Chute Mud Creek (Upper) 111,022 28.5% 31,641 Grand Chute Mud Creek (Lower) 1,939,320 28.5% 552,706
Grand Chute Fox River Lake Winn. to
Middle Appleton Dam 44,492 65.2% 29,009 Green Bay East River (Lower) 1,070,479 40.0% 428,192 Green Bay Baird Creek (Upper) 1,023,586 40.0% 409,435 Green Bay Baird Creek (Lower) 1,020,812 40.0% 408,325 Green Bay Bower Creek (Lower) 47,303 40.0% 18,921 Green Bay Dutchman Creek (Lower) 297,353 40.0% 118,941
Green Bay Lower Duck Creek
(Lower) 611,657 40.0% 244,663
Green Bay Lower Duck Creek
(Upper unimpaired) 380,435 40.0% 152,174
Green Bay Lower Green Bay
(Pt du Sable) 1,740,380 40.0% 696,152
Green Bay lower segment -- Fox
River 2,254,509 65.2% 1,469,940 Greenville Mud Creek (Upper) 213,233 28.5% 60,771 Greenville Mud Creek (Lower) 561,373 28.5% 159,991
87 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 2-B (continued). MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements (continued)
MS4 Watershed Location TSS Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Harrison Garners Creek 562,997 49.9% 280,936 Harrison middle-stem Fox River ** See below Hobart Ashwaubenon Creek 218,757 40.0% 87,503
Hobart Dutchman Creek (Middle
unimpaired) 1,352,752 40.0% 541,101 Hobart Dutchman Creek (Lower) 497,247 40.0% 198,899
Hobart Lower Duck Creek
(Upper unimpaired) 1,157,876 40.0% 463,150
Hobart Lower Duck Creek
(Lower) 331,440 40.0% 132,576
Hobart Trout Creek (unimpaired) 388,097 40.0% 155,239
Howard Lower Duck Creek
(Upper unimpaired) 4,542 40.0% 1,817
Howard Lower Duck Creek
(Lower) 2,127,384 40.0% 850,954
Howard Trout Creek 25,977 40.0% 10,391
Howard Lower Green Bay (Dead
Horse Bay) 328,339 40.0% 131,336
Howard lower segment -- Fox
River *** see below
Kaukauna Apple Creek (Upper) 276,654 40.0% 110,661
Kaukauna Plum Creek (Lower) 15,798 40.0% 6,319
Kaukauna Kankapot Creek (Lower) 529,697 40.0% 211,879
Kaukauna # Kankapot Creek Upper 19,456 40.0% 7,782
Kaukauna Garners Creek 66,331 49.9% 33,099
Kaukauna middle-stem Fox River 943,124 65.2% 614,917
Kimberly Garners Creek 73,181 49.9% 36,517
Kimberly middle-stem Fox River 511,382 65.2% 333,421
Lawrence Apple Creek 21,308 40.0% 8,523
Lawrence Ashwaubenon Creek 314,128 40.0% 125,651
Lawrence Dutchman Creek (Lower) 118,280 40.0% 47,312
Lawrence middle-stem Fox River 22,041 65.2% 14,371
88 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 2-B (continued) MS4 sub-HUC-12 watershed estimated total phosphorus reduction requirements (continued)
MS4 Watershed Location TSS Load (lbs/yr) TMDL reduction
goal %
Reduction
needed
(lbs/yr) Ledgeview Lower East River (Lower) 32,333 40.0% 12,933 Ledgeview Bower Creek (Lower) 115,530 40.0% 46,212 Ledgeview middle-stem Fox River 111,659 65.2% 72,802 Little Chute Apple Creek (Upper) 551,235 40.0% 220,494 Little Chute middle-stem Fox River 555,166 65.2% 361,968
Menasha Fox River Lake Winn. to
Middle Appleton Dam 1,438,645 65.2% 937,996
Neenah Neenah Slough (Upper) 282,958 40.0% 113,183 Neenah Neenah Slough (Middle) 210,472 40.0% 84,189 Neenah Neenah Slough (Lower) 877,454 40.0% 350,982
Neenah Fox River Lake Winn. to
Middle Appleton Dam 341,343 65.2% 222,556 Scott Lower Green Bay 249,475 40.0% 99,790 Suamico Duck Creek 315,628 40.0% 126,251 Suamico Lower Green Bay 1,501,482 40.0% 600,593 T. Menasha Mud Creek 444,359 28.5% 126,642
T. Menasha Fox River Lake Winn. to
Middle Appleton Dam 2,354,142 65.2% 1,534,901
T. Neenah Fox River Lake Winn. to
Middle Appleton Dam 364,948 65.2% 237,946 T. Neenah Neenah Slough (Upper) 547,346 40.0% 218,939 T. Neenah Neenah Slough (Middle) 121,209 40.0% 48,484 T. Neenah Neenah Slough (Lower) 310,971 40.0% 124,388 UWGB Lower Green Bay 194,990 40.0% 77,996
89 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Table 3-B MS4 estimated annualized unit costs
MS4 TP Unit
Cost ($/lb)
TSS Unit
Cost
($/ton) Combined Unit Cost
($/(TP lb +TSS ton))
Allouez $ 2,805 $ 6,499 $ 1,958
Appleton $ 2,292 $ 5,614 $ 1,628
Ashwaubenon $ 2,496 $ 7,598 $ 1,878
Bellevue $ 883 $ 3,401 $ 700
Buchanan $ 2,008 $ 10,480 $ 1,686
Combined Locks $ 2,505 $ 9,353 $ 1,976
De Pere $ 2,531 $ 5,551 $ 1,739
Grand Chute $ 2,015 $ 10,843 $ 1,699
Green Bay $ 2,158 $ 6,232 $ 1,603
Greenville $ 2,320 $ 13,518 $ 1,980
Harrison $ 1,664 $ 9,566 $ 1,416
Hobart $ 2,637 $ 11,264 $ 2,137
Howard $ 2,245 $ 9,013 $ 1,798 Kaukauna $ 2,278 $ 5,251 $ 1,588 Kimberly $ 3,170 $ 6,323 $ 2,113 Lawrence $ 2,829 $ 11,230 $ 2,260
Ledgeview $ 3,480 $ 9,544 $ 2,555 Little Chute $ 1,709 $ 4,116 $ 1,207 Menasha $ 2,641 $ 4,184 $ 1,619 Neenah $ 2,772 $ 6,300 $ 1,924
Scott $ 2,425 $ 9,941 $ 1,951 Suamico $ 2,115 $ 8,642 $ 1,699 T. Menasha $ 2,282 $ 4,348 $ 1,497 T. Neenah $ 2,874 $ 6,276 $ 1,971
UWGB $ 2,962 $ 12,153 $ 2,380
90 | P a g e
APPENDIX C
Attenuation Tables
91 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
Ab
ov
e M
idd
le A
pp
leto
n D
am
HUC-12 91389 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0202 - Mud Creek Incremental load of reach 91389 39,895
04030204 0201 - Little Lake Butte des Mortes Load at end of reach 91389 39693.33512 0.994945109 99.49% 0.51%
04030204 0205 - Garners Creek - Fox River Load at end of reach 91390 (Appleton Dam) 39546.13549 0.996291578 99.13% 0.87%
04030204 0205 - Garners Creek - Fox River Load at end of reach 12278 39399.48173 0.996291578 98.76% 1.24%
04030204 0205 - Garners Creek - Fox River Load at end of reach 11240 39294.1164 0.997325718 98.49% 1.51%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 65686 39189.03285 0.997325718 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 39189.03285 1 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (Depere Dam) 39189.03285 1 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 39189.03285 1 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 39189.03285 1 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 39189.03285 1 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 39189.03285 1 98.23% 1.77%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 39189.03285 1 98.23% 1.77%
HUC-12 91390 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0205 - Garners Creek - Fox River Incremental load of reach 91390 217
04030204 0205 - Garners Creek - Fox River Load at end of reach 91390 (Appleton Dam) 216.1952724 0.996291578 99.63% 0.37%
04030204 0205 - Garners Creek - Fox River Load at end of reach 12278 215.3935291 0.996291578 99.26% 0.74%
04030204 0205 - Garners Creek - Fox River Load at end of reach 11240 214.8175061 0.997325718 98.99% 1.01%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 65686 214.2430235 0.997325718 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 214.2430235 1 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (Depere Dam) 214.2430235 1 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 214.2430235 1 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 214.2430235 1 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 214.2430235 1 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 214.2430235 1 98.73% 1.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 214.2430235 1 98.73% 1.27%
92 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
Bet
wee
n M
idd
le A
pp
leto
n D
am &
De P
ere
Dam
HUC-12 12278 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0205 - Garners Creek - Fox River Incremental load of reach 12278 40660 100.00%
04030204 0205 - Garners Creek - Fox River Load at end of reach 12278 40509.21556 0.996291578 99.63% 0.37%
04030204 0205 - Garners Creek - Fox River Load at end of reach 11240 40400.8825 0.997325718 99.36% 0.64%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 65686 40292.83914 0.997325718 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 40292.83914 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 40292.83914 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 40292.83914 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 40292.83914 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 40292.83914 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 40292.83914 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 40292.83914 1 99.10% 0.90%
HUC-12 11240 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0205 - Garners Creek - Fox River Incremental load of reach 11240 25077 100.00%
04030204 0205 - Garners Creek - Fox River Load at end of reach 11240 25009.93703 0.997325718 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 65686 24943.05341 0.997325718 99.47% 0.53%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 24943.05341 1 99.47% 0.53%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 24943.05341 1 61.90% 38.10%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 24943.05341 1 99.47% 0.53%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 24943.05341 1 99.47% 0.53%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 24943.05341 1 99.47% 0.53%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 24943.05341 1 99.47% 0.53%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 24943.05341 1 99.47% 0.53%
93 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12 90601 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0203 - Kankapot Creek Incremental load of reach 90601: 8744 100.00%
04030204 0203 - Kankapot Creek Load at end of reach 90601 8370.244549 0.957255781 95.73% 4.27%
04030204 0203 - Kankapot Creek Load at end of reach 11241 8339.20415 0.996291578 95.37% 4.63%
04030204 0205 - Garners Creek - Fox River Load at end of reach 11240 8316.902766 0.997325718 95.12% 4.88%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 65686 8294.661023 0.997325718 94.86% 5.14%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 8294.661023 1 94.86% 5.14%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 8294.661023 1 33.25% 66.75%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 8294.661023 1 94.86% 5.14%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 8294.661023 1 94.86% 5.14%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 8294.661023 1 94.86% 5.14%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 8294.661023 1 94.86% 5.14%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 8294.661023 1 94.86% 5.14%
HUC-12 11241 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0203 - Kankapot Creek Incremental load of reach 11241 379 100.00%
04030204 0203 - Kankapot Creek Load at end of reach 11241 377.5945081 0.996291578 99.63% 0.37%
04030204 0205 - Garners Creek - Fox River Load at end of reach 11240 376.5847139 0.997325718 99.36% 0.64%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 65686 375.5776201 0.997325718 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 375.5776201 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 375.5776201 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 375.5776201 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 375.5776201 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 375.5776201 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 375.5776201 1 99.10% 0.90%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 375.5776201 1 99.10% 0.90%
94 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12 90365 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0204 - Plum Creek Incremental load of reach 90365 9150 100.00%
04030204 0204 - Plum Creek Load at end of reach 90365 8835.904949 0.965672672 96.57% 3.43%
04030204 0205 - Garners Creek - Fox River Load at end of reach 65686 8812.275247 0.997325718 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 8812.275247 1 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 8812.275247 1 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 8812.275247 1 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 8812.275247 1 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 8812.275247 1 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 8812.275247 1 96.31% 3.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 8812.275247 1 96.31% 3.69%
HUC-12 11238 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0402 - Apple Creek Incremental load of reach 11238 15996 100%
04030204 0402 - Apple Creek Load at end of reach 11238 15953.22219 0.997325718 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90226 15953.22219 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 15953.22219 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 15953.22219 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 15953.22219 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 15953.22219 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 15953.22219 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 15953.22219 1 99.73% 0.27%
95 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12 65686 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam) Incremental load of reach 65686 72 100.00%
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam) Load at end of reach 65686 71.8074517 0.997325718 99.73% 0.27%
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam) Load at end of reach 90226 71.8074517 1 99.73% 0.27%
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam) Load at end of reach 91411 (DePere Dam) 71.8074517 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 71.8074517 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 71.8074517 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 71.8074517 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 71.8074517 1 99.73% 0.27%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 71.8074517 1 99.73% 0.27%
HUC-12 90226 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of G.B. - Fox River (S. of
DePere Dam) Incremental load of reach 90226 2401 100.00%
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam Load at end of reach 90226 2401 1 100.00% 0.00%
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam Load at end of reach 91411 (DePere Dam) 2401 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 2401 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 2401 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 2401 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 2401 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91415 (Green Bay) 2401 1 100.00% 0.00%
96 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam 91411 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of G.B. - Fox River (S. of
De Pere Dam Incremental load of reach 91411 2846 100.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91411 (DePere Dam) 2846 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 2846 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 2846 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 2846 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 2846 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 2846 1 100.00% 0.00%
HUC-12
Bel
ow
De
Per
e D
am
04030204 0403 - Ashwaubenon Creek 90358 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0403 - Ashwaubenon Creek Incremental Load of reach 90358 8104
04030204 0403 - Ashwaubenon Creek Load at end of reach 90358 7075.373784 0.87307179 87.31% 12.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11236 7075.373784 1 87.31% 12.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 7075.373784 1 87.31% 12.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 7075.373784 1 87.31% 12.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 7075.373784 1 87.31% 12.69%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 7075.373784 1 87.31% 12.69%
Load at end of reach 91415 (Green Bay) 7075.373784 1 87.31% 12.69%
HUC-12 04030204 0403 - Ashwaubenon Creek 11236 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0403 - Ashwaubenon Creek Incremental load of reach 11236 6333
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11236 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 6333 1 100.00% 0.00%
97 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12 (continued)
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 6333 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 6333 1 100.00% 0.00%
HUC-12
04030204 0403 - Ashwaubenon Creek 90608 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0403 - Ashwaubenon Creek Incremental load of reach 90608 6333
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90608 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 6333 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 6333 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 6333 1 100.00% 0.00%
HUC-12 04030204 0405 - City of Green Bay - Fox River 11235 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of Green Bay - Fox River Incremental load of reach 11235 219
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 219 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 219 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 219 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 219 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 219 1 100.00% 0.00%
98 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12 04030204 0405 - City of Green Bay - Fox River 91414 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of Green Bay - Fox River Incremental load of reach 91414 6770
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 6770 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 6770 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 6770 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 6770 1 100.00% 0.00%
HUC-12 04030204 0405 - City of Green Bay - Fox River 11233 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of Green Bay - Fox River Incremental load of reach 11233 95
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 95 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 95 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 95 1 100.00% 0.00%
HUC-12 04030204 0405 - City of Green Bay - Fox River 90227 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of Green Bay - Fox River Incremental load of reach 90227 861
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 861 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 861 1 100.00% 0.00%
HUC-12
04030204 0405 - City of Green Bay - Fox River 91415 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0405 - City of Green Bay - Fox River Incremental load of reach 91415 1702
Load at end of reach 91415 (Green Bay) 1702 1 100.00% 0.00%
99 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
HUC-12
04030204 0404 - Dutchman Creek 11234 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0404 - Dutchman Creek Incremental load of reach 11234 7504
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11234 7504 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11235 7504 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 91414 7504 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11233 7504 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 7504 1 100.00% 0.00%
Load at end of reach 91415 (Green Bay) 7504 1 100.00% 0.00%
HUC-12
04030204 0301 - Upper East River 65606 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0301 - Upper East River Incremental load of reach 65606 17815
04030204 0302 - Bower Creek, 04030204 0303
- Baird Creek, 04030204 0304 - Lower East
River Load at end of reach 65606 12828.86794 0.720116079 72.01% 27.99%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11243 12828.86794 1 72.01% 27.99%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 12828.86794 1 72.01% 27.99%
Load at end of reach 91415 (Green Bay) 12828.86794 1 72.01% 27.99%
HUC-12 04030204 0302 - Bower Creek, 04030204 0303
- Baird Creek, 04030204 0304 - Lower East
River 11243 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0302 - Bower Creek, 04030204 0303
- Baird Creek, 04030204 0304 - Lower East
River Incremental load of reach 11243 26243
04030204 0405 - City of Green Bay - Fox River Load at end of reach 11243 26243 1 100.00% 0.00%
04030204 0405 - City of Green Bay - Fox River Load at end of reach 90227 26243 1 100.00% 0.00%
100 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System Delivery Fractions
Duck
Creek
HUC-12 65604 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 102 - Upper Duck Creek, 04030204
103 - Oneida Creek, 04030204 104 - Middle
Duck Creek Incremental Load of reach 65604 25,514
04030204 102 - Upper Duck Creek, 04030204
103 - Oneida Creek, 04030204 104 - Middle
Duck Creek Load at end of reach 65604 18855.53091 0.739026845 73.90% 26.10%
04030204 0105 - Trout Creek, 04030204 0106 -
Lower Duck Creek Load at end of reach 90216 16318.50396 0.86544919 63.96% 36.04%
04030204 0106 - Lower Duck Creek Load at end of reach 11050 (Green Bay) 16318.50396 1 63.96% 36.04%
HUC-12 90216 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0105 - Trout Creek, 04030204 0106 -
Lower Duck Creek Incremental load of reach 90216 3912
04030204 0105 - Trout Creek, 04030204 0106 -
Lower Duck Creek Load at end of reach 90216 3385.637232 0.86544919 86.54% 13.46%
04030204 0106 - Lower Duck Creek Load at end of reach 11050 (Green Bay) 3385.637232 1 86.54% 13.46%
HUC-12 11050 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0106 - Lower Duck Creek Incremental load of reach 11050 3853
04030204 0106 - Lower Duck Creek Load at end of reach 11050 (Green Bay) 3853 1 100.00% 0.00%
101 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Flow Diagrams for HUC-12 and SPARROW Decision Support System Reach ID Cross Reference
102 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
Flow Diagrams for HUC-12 and SPARROW Decision Support System Reach ID Cross Reference
103 | Lower Fox River Basin Water Quality Trading Economic Feasibility Assessment
USGS Sparrow Decision Support System, Delivery Fractions (SPARROW’s unique subwatershed ID is in column 2)
Reaches in Duck Creek
HUC-12 65604 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 102 - Upper Duck Creek, 04030204 103 -
Oneida Creek, 04030204 104 - Middle Duck Creek Incremental Load of reach 65604 25,514
04030204 102 - Upper Duck Creek, 04030204 103 -
Oneida Creek, 04030204 104 - Middle Duck Creek Load at end of reach 65604 18855.53091 0.739026845 73.90% 26.10%
04030204 0105 - Trout Creek, 04030204 0106 - Lower
Duck Creek Load at end of reach 90216 16318.50396 0.86544919 63.96% 36.04%
04030204 0106 - Lower Duck Creek Load at end of reach 11050 (Green Bay) 16318.50396 1 63.96% 36.04%
HUC-12 90216 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0105 - Trout Creek, 04030204 0106 - Lower
Duck Creek Incremental load of reach 90216 3912
04030204 0105 - Trout Creek, 04030204 0106 - Lower
Duck Creek Load at end of reach 90216 3385.637232 0.86544919 86.54% 13.46%
04030204 0106 - Lower Duck Creek Load at end of reach 11050 (Green Bay) 3385.637232 1 86.54% 13.46%
HUC-12 11050 Incremental Load Delivery Fraction % Carried % Attenuated
04030204 0106 - Lower Duck Creek Incremental load of reach 11050 3853
04030204 0106 - Lower Duck Creek Load at end of reach 11050 (Green Bay) 3853 1 100.00% 0.00%