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ACD 31 ADDENDUM TO THE REPAIR REPORT
Maple Grove, MN | HEI No. 5555-230 April 8, 2015
Anoka County Ditch 31 Repair Report Addendum
for the
Rice Creek Watershed District
4325 Pheasant Ridge Drive Suite 611
Blaine, Minnesota 55449-4539 I hereby certify that this plan, specification, or report, was prepared by me or under my direct supervision, and that I am a duly Registered Professional Engineer under the laws of the State of Minnesota. Christopher C. Otterness Minn. Reg. No. 41961 Date: April 8, 2015 Houston Engineering, Inc. Suite 140 6901 East Fish Lake Road Maple Grove, Minnesota 55369 763.493.4522 (Phone) 763.493.5572 (Fax) www.houstonengineeringinc.com HEI Project No. R145555-230
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 1 of 10
ANOKA COUNTY DITCH 31
ADDENDUM TO THE REPAIR REPORT
1.0 INTRODUCTION
This document is an addendum to the report titled Anoka County Ditch 31 Repair Report.
This report (hereinafter referred to as the “Repair Report”), identified and evaluated four repair
alternatives for the Anoka County Ditch 31 (ACD 31) legal drainage system, for the purposes of
serving present agricultural drainage, current and future municipal stormwater, ecological and
water quality needs. The alternatives ranged from use of the existing system conveyance and minor
maintenance (“do nothing” alternative) to a repair to the as-constructed and subsequently improved
condition (“full repair” alternative). Each alternative was evaluated using hydrologic and hydraulic
modeling, evaluated against a set of design criteria, and then evaluated with regard to cost and
relative benefit.
Houston Engineering, Inc. (the “Engineer”) completed the Repair Report on February 17,
2010 and subsequently orally presented the report to the Rice Creek Watershed District (RCWD)
Board of Managers. The four alternatives analyzed included:
Alternative 1: Existing System Conveyance Alternative (see Figure A-1),
Alternative 2: As-Constructed and Subsequently Improved Alternative (see Figure
A-2),
Alternative 3: Active Agricultural Repair Alternative (see Figure A-3), and
Alternative 4: Resource Management Plan Alternative (see Figure A-4)
The Engineer’s Recommended Alternative based upon the ability to achieve the design
criteria, was the Resource Management Plan Alternative (#4). No action was taken by the Board
to execute said alternative at that time (circa 2010).
Subsequent to the completion of the Repair Report, the RCWD completed several public
drainage system repair projects with a scope of work similar to the Engineer’s Recommended
Alternative for ACD 31. Based on the experiences from the completion of these projects, District
staff and the Engineer have progressively gained a better understanding of project costs and
regulatory challenges associated with public drainage system repair projects. Consequently, the
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 2 of 10
RCWD Board of Managers requested the Engineer to revise the project costs detailed in the Repair
Report and revisit the conclusions based on these costs.
The purpose of this addendum is to provide updated analysis and recommendations of the
four alternatives evaluated within the Repair Report, based on:
1. Refinement of the lateral drainage effects analysis and wetland mitigation
requirements;
2. Updated cost information pertaining to construction, easements, and land
acquisition; and
3. The recently completed Historical Review Memorandum Addendum, which
includes test pit analysis confirming As Constructed and Subsequently Improved
Condition (ACSIC).
This addendum updates the wetland impacts analysis and Preliminary Opinion of Probable
Construction Costs (POPCC) for each alternative and revisit conclusions based on the factors to
provide a new preferred alternative. It is intended that this addendum, coupled with the findings
of the Repair Report, will be used by the Board to order a project containing the components
outlined in their preferred alternative.
2.0 WETLAND IMPACTS AND MITIGATION
The wetland impacts of the four alternatives were previously assessed using the methods
described in Section 3.0 of the Repair Report. This methodology for determining the lateral
drainage effects in the wetland impact assessment is identical to that used in two subsequent repair
reports (ACD 10-22-32 and ACD 53-62) completed by the District. However, these subsequent
repair reports added an additional step in verifying the impacts – namely, utilizing recent wetland
delineations to confirm the assumptions used in the lateral effects calculations. Comparing the
delineated Type 3, 4, and 5 wetlands to the calculated lateral drainage effects revealed that the
drainable porosity and/or hydraulic conductivity of the underlying soils at several locations was
far different than the standard (“book”) values for these soils. Notably, the repair report
determined that highly organic soils (e.g. peat and muck) adjacent to the public drainage system
exhibited far less permeability than would be expected from those soils based on soils parameters
detailed in the national soils database (SSURGO). Therefore, it could be concluded that no repair
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 3 of 10
or modification to the public drainage system in these locations would result in lateral drainage
effects.
To evaluate the validity of the wetland impact assessment in the ACD 31 Repair Report,
the lateral drainage effects previously calculated for existing (2009) conditions were compared to
the 2009 wetland delineation (see Figure A-5). The lateral effects analysis indicates that every
Type 3, 4, or 5 wetland bisected by or adjacent to the ACD 31 public drainage system would be
partially or wholly drained assuming standard porosity and hydraulic conductivity values for the
underlying soils (peat). This indicates that soils at each of these locations has a much lower
permeability than indicated in the soils database, and that these wetlands will not be drained by
any of the four alternatives. Since the calculated lateral effects for the three “repair” alternatives
do not extend into any other wetland complexes beyond that of existing conditions, it can be
concluded that none of the alternatives will result in impacts to Type 3, 4, or 5 wetlands and
therefore require mitigation.
3.0 PRELIMINARY OPINION OF PROBABLE CONSTRUCTION COST
The Preliminary Opinions of Probable Construction Cost (POPCCs) presented in the
Repair Report have been updated for each of the four alternatives, using unit prices from recent
RCWD public drainage system projects. The POPCC for each repair alternative also now includes
replacement of every corrugated metal culvert (CMP) within the portions of the public drainage
system to be repaired. Recent public drainage system repairs completed by the RCWD revealed
that existing CMPs along the public drainage system almost universally exhibited severe corrosion,
sedimentation, and eminent failure. These culverts are identified in Table A-1. Thus, these
projects include replacement of all of the CMPs, regardless of whether the existing culverts were
properly sized or at the proper elevation. Likewise, the updated POPCC assumes excavation will
be required at all locations of the public drainage system designated for repair, and not solely at
locations where the open channel bottom is above the ACSIC. Finally, the wetland replacement
acreage was updated based on the refined lateral drainage effects analysis used to determine
wetland mitigation requirements.
A full tabulation of individual item quantities and costs is included in Appendix A. An
overall financial comparison of costs is tabulated in Table A-2 The POPCC indicates that each of
the repair alternatives (#2, 3, &4) have “similar” construction costs (i.e. within 10% of each other).
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 4 of 10
Table A-1 – Culvert Crossings
Existing Structure Data (b) Crossing Data Required Replacements
Station (a) Reach Size and Type Description Alternative 2 Alternatives 3 & 4
Existing Structures 38+81 Main Trunk 36"x88' CMP Kettle River Blvd. (C.R. 62) Replace in kind (c) Replace in kind (c) 56+46 Main Trunk 36"x52' HDPE 167th Ave. Replace in kind (c) Replace in kind (c) 74+31 Main Trunk 24"x15' CMP Field crossing Replace w/30" HDPE Replace w/30" HDPE 75+31 Main Trunk 18"x24' RCP 170th Ave. Replace w/30" Replace w/30"
79+15 Main Trunk 30"x21' CMP Field crossing Replace with HDPE, Raise field road
Replace with HDPE, Raise field road
82+30 Main Trunk 36"x21' CMP Field crossing Replace with HDPE, Raise field road
Replace with HDPE, Raise field road
83+84 Main Trunk 36"x21' CMP Field crossing Replace with HDPE, Raise field road
Replace with HDPE, Raise field road
110+77 Main Trunk 48"x65' CMP W. Broadway Ave. (CSAH 18) Replace with RCP Replace with RCP
45+01 Branch 1 36"x23' CMP Field crossing Replace with HDPE (c), raise field road
Replace with HDPE (c), raise field road
60+40 Branch 1 27"x43"x49' CMP Arch W. Broadway Ave. (CSAH 18) Replace with RCP Replace with RCP 13+65 Branch 2 36"x40' CMP Driveway Replace with HDPE (c) Replace with HDPE (c)
48+98 Branch 2 30"x30' CMP Driveway Replace with HDPE (c), raise field road
Replace with HDPE (c), raise field road
52+96 Branch 2 24"x50' CMP Notre Dame St. Replace in kind (c) Replace in kind (c) 6+37 Branch 5 18"x25' RCP Driveway ok ok 0+53 Branch 6 36"x53' CMP Furman St. Replace in kind (c) Replace in kind (c) 12+09 Branch 6 24"x32' CMP Driveway Replace with HDPE (c) Replace with HDPE (c) 1+89 Branch 7 24"x26' CMP Driveway Replace with HDPE (c) Replace with HDPE (c) 9+16 Private 36"x110' CMP Kettle River Blvd. (C.R. 62) ok Replace in kind (c) 14+91 Private 30"x70' CMP Field crossing ok Replace with HDPE (c)
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 5 of 10
Existing Structure Data (b) Crossing Data Required Replacements
Station (a) Reach Size and Type Description Alternative 2 Alternatives 3 & 4
20+50 Private 24"x13' CMP Field crossing ok Replace w/30" HDPE, raise field road
31+01 Private 36"x11' CMP Field crossing ok Replace with HDPE (c) 33+69 Private 36"x51' CMP Notre Dame St. ok Replace in kind (c) 36+40 Private 36"x41' CMP Driveway ok Replace with HDPE (c) 41+16 Private 36"x29' CMP Driveway ok Replace with HDPE (c) 43+18 Private 36"x30' CMP Driveway ok Replace with HDPE (c) 45+06 Private 15"x20' CMP Driveway ok Replace w/36" HDPE 55+65 Private 36"x21' CMP Field crossing ok Replace with HDPE (c) Proposed Structures 15+10 Branch 1 24"x30' HDPE Field crossing Install Install
a)Based on upstream invert b) Based on 2008 HEI survey or 2005 EOR survey c) Lower grade
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 6 of 10
Table A-2 – Preliminary Opinion of Probable Construction Costs
Alternative
Description
Alternative 1 Existing System
Conditions
Alternative 2 As-Constructed and
Subsequently Improved
Alternative
Alternative 3 Active
Agricultural Repair
Alternative
Alternative 4 Resource
Management Plan Alternative
Public Drainage System Infrastructure $59,831 $422,471 $211,246 $211,246 Land for Infrastructure (Easement and Land Acquisition)* $270,000 $0 $225,000 $225,000
Public Drainage System Wetland Mitigation** $0 $0 $0 $0
Infrastructure at Public Roadways $0 $76,072 $87,704 $87,704
Engineering/Legal/Admin $78,449 $209,854 $181,145 $181,145
Contingency $11,966 $99,709 $59,790 $59,790
Total $420,246 $808,106 $764,885 $764,885 *See Appendix G of the Repair Report for identification and location of required easement acquisitions.
** Assumes COE will concur that no mitigation is required per the Clean Water Act
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 7 of 10
4.0 PROJECT FEASIBILITY AND ENGINEER’S RECOMMENDATION
4.1 Basis for the Recommendation
As outlined in the Repair Report, the determination of project feasibility is based upon
several criteria including:
• The ability to attain the agricultural drainage, municipal stormwater conveyance, and
ecological and natural resource design criteria as presented in Section 2.0 of the Repair
Report (Description of Alternatives), and to provide the desired level of service for
agricultural drainage and future stormwater management consistent with these criteria;
• The relative magnitude of the potential adverse environmental impacts, opportunities
for ecological and natural resource enhancement, and the likelihood of obtaining the
necessary regulatory approvals and permits;
• Implementing and constructing the repair in a manner, which allows repairs made to
serve the immediate agricultural drainage need and to also serve the future stormwater
management needs associated with development;
• The relative benefits and the Preliminary Opinions of Probable Construction Cost; and,
• The perceived constructability and maintainability of the project.
It is the objective of the Engineer’s recommendations to seek a balance between all of the
needs identified by the Board of Managers, including agricultural and municipal stormwater needs,
ecological and natural resource conservation and enhancement, and financial obligations while
balancing the items discussed within the section. Table A-3 presents a ranking of the alternatives
based on the level of service for agricultural drainage and flood protection, ecological impacts,
and both initial (construction) cost and long term maintenance.
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 March 23, 2015 Addendum to the ACD 31 Repair Report Page 8 of 10
Table A-3 Relative Ranking of the Alternatives
Alternative
Level of Service / Function
Relative Negative Impact to Resource
Ranking of Cost (Low to High)*
Agricultural Drainage
Overland Surface
Water Outlet Wetlands Construction
Cost
Future Maintenance
Cost
Alternative 1: Existing System Conveyance Low Low Low 1 4
Alternative 2: As Constructed and Subsequently Improved High High Low 2 1
Alternative 3. Active Agricultural Repair
Moderate / High Moderate Low 2 2
Alternative 4. Resource Management Plan Moderate Moderate Low 2 3
*For the purposes of this ranking, estimated costs within 10% of each other are considered “identical”.
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 9 of 10
The feasibility of an alternative is rarely based solely on cost, and considerable caution is
needed when reviewing and using the Opinions of Probable Construction Costs, especially with
regard to the selection of a preferred alternative by the Board of Managers. The direct comparison
of the Opinions of Probable Construction Costs is challenging because of the potential additional
or “hidden costs.” For instance, alternatives that repair only a portion of the system (or no repairs
at all) will likely have much greater long-term maintenance costs than complete repair of the entire
public drainage system.
In addition to the technical criteria (i.e., design goals) the Engineer’s recommendation to
the Board of Managers also includes and considers several factors unrelated to performance of the
public drainage system, but to various non-technical factors. Many of these factors are “intangible”
and the result of discussions with the landowners on site and at public meetings. The importance
and weight of these various factors should be deliberated by the Board of Managers when reaching
an independent conclusion about the recommended repair alternative.
4.2 Engineer’s Recommendation
Alternative 1 (Existing System Conditions) does not provide a restoration of drainage
function to lands historically drained by the ACD 31 public drainage system, and thus does not
meet the repair objectives and is not recommended. The three remaining alternatives (#2, 3, & 4)
each have a similar construction cost (within 10%). However, Alternative 2 repairs over twice as
much length in the public drainage system, and provides a greater level of drainage function (up
to a foot lower water surface levels for the 2-year, 24-hour rainfall event) than the other
alternatives. Likewise, long term maintenance costs for this alternative will likely be substantially
less than for Alternatives #3 and #4 because Alterative 2 repairs the entire public drainage system,
not just a portion of it.
Based upon the design criteria established in the Repair Report and the relative benefits
and costs, the Engineer recommends construction of the As-Constructed and Subsequently
Improved Alternative (ACSIA), aka Alternative #2. The recommended alternative is expected to
restore agricultural drainage function to the ACD 31 system (see Figure A-2). As noted above,
Alternative 2 will not result in the drainage of wetlands requiring mitigation.
Anoka County Ditch 31 Addendum to Repair Report
RCWD Account No. 60-17 HEI Project No. R145555-230 April 8, 2015 Addendum to the ACD 31 Repair Report Page 10 of 10
The Engineer concludes that the repairs represented by implementing the Alternative 2 are
necessary to meet current agricultural drainage based on considerations presented within this
Repair Report, and that the repairs are in the best interest of the property owners.
The repairs are expected to return the capacity of the system, to serve the original intended
purpose of providing agricultural drainage, provide the infrastructure (upon replacement) for the
future management of stormwater runoff resulting from urbanization of the landscape. The
recommended alternative is believed to balance the need to provide serviceable drainage to
agricultural land, the future need to manage stormwater runoff, and the desire to minimize
environmental impacts while implementing the best value alternative.
The Board of Managers retains the decision whether to accept, reject or modify the
Engineer’s Recommendation. The repairs recommended by the Engineer are consistent with the
objectives and policies identified with the current Watershed Management Plan, dated January
2012, approved by the Board of Water and Soil Resource.
GrWX
GsWX
GÈWX
Lamprey Pass State Wildlife Refuge
Columbus
Private
Private
Branch
3
Branch
5
Private
Branch 6
Bran
ch 7
Private
PrivateBranch 1
Branch 1
Branch
1
Branch 2Branch 2
Main Trunk
Main Trunk
Main
Trunk
Rice CreekWatershed District
ACD 31Repair Report
0 0.25 0.50.125Miles
¶Notes: Hydrology reflects current land use. The agricultural polygons were digitized and classifiedfrom 2006 Twin Cities aerials and FSA 2008 aerials.Sources: TLG, RCWD, MN DOT
Anoka County
Flow DirectionPublic Through RealignmentPublic System Out of District Boundary
Private Open ChannelPublic Open ChannelSubwatershedsN
N N
N
N NNN
N
N
NN N
NNN NN
N NN
NNN
NN
NN
N
NNNN
N
N
NNN
NN
NN
N
NN
N
N
N
N
NN N
NNN
NNNN
N
N
N
N
N
N N
N
N
NN
NN
N
NN
NNN Grass Hay/ Pasture
CultivatedCounty RoadsColumbus RMP BoundaryRCWD Boundary (2009)State/Local ParksLakes
Anoka
WashingtonHennepin
RamseyProject
Location Map
Figure A-1 ACD 31 Existing System Conveyance Alternative (#1)Scale: Drawn by: Checked by: Project No.: Date: Sheet:AS SHOWN SMW 5555-060.17 8/06/2009
GrWX
GsWX
GÈWX
Lamprey Pass State Wildlife Refuge
Columbus
Branch
3
Branch
5
PrivateBranch 6
Bran
ch 7
Private
PrivateBranch 1
Branch
1
Branch 2Branch 2
Main Trunk
Main
Trunk
Rice CreekWatershed District
ACD 31Repair Report
0 0.25 0.50.125Miles
¶Note: Hydrology reflects current land use. The agricultural polygons were digitized and classifiedfrom 2006 Twin Cities aerials and FSA 2008 aerials.Sources: TLG, RCWD, MN DOT
Anoka County
NNN
NNN
N
N
N
NNN
NN
N NNN
NN
N
NNNN
N
N
N
N
N
N
NNN
NN
NN
N N
NN
NNNN
N
NNN
NN N
N N
N N
Flow DirectionRepair to ACSIC - Outside Current RCWD Bndry
Repair to As Constructed ProfilePrivate Open Channel - No Repairs Public Spot Maintenance to Existing Profile
SubwatershedsCounty RoadsColumbus RMP BoundaryRCWD Boundary (2009)Grass Hay/ PastureCultivatedLocal ParksLakes
Anoka
WashingtonHennepin
RamseyProject
Location Map
Figure A-2 ACD 31As Constructed and Subsequently Improved Alternative (#2)Scale: Drawn by: Checked by: Project No.: Date: Sheet:AS SHOWN SMW 5555-060.17 8/12/2009
GrWX
GsWX
GÈWX
RiceCree
k
Lamprey Pass State Wildlife Refuge
Columbus
Private
Branch
3
Branch
5
Private
Branch 6
Bran
ch 7
PrivateBranch 1
Branch
1
Branch 2Branch 2
Main Trunk
Main
Trunk
Rice CreekWatershed District
ACD 31Repair Report
0 0.25 0.50.125Miles
¶Note: Hydrology reflects current land use. The agricultural polygons were digitized and classifiedfrom 2006 Twin Cities aerials and FSA 2008 aerials.Sources: TLG, RCWD, MN DOT
Anoka County
NN
N
N
N
NN
N
N
NN
N
NNNN
N
N
NNN
N NN
N
NNN
NN
NN NNNN
NN
NNN
N
NN
NN
NN
NN
N
N
N
NN
N
N
NN
NN
N
Flow DirectionHigh Spots in Open Channel to be Repaired
Private to become publicTo become Administered by RCWDPublic System Outside Current RCWD Bndry
Public Spot Maintenance to Existing Profile
Repair to As Constructed ProfilePrivate Open Channel - No RepairsPublic Open Channel - No Repairs
SubwatershedsGrass Hay/ PastureCultivatedCounty RoadsColumbus RMP BoundaryRCWD Boundary (2009)Local ParksLakes
Anoka
WashingtonHennepin
RamseyProject
Location Map
Figure A-3 ACD 31 Active Agricultural Repair Alternative (#3)Scale: Drawn by: Checked by: Project No.: Date: Sheet:AS SHOWN SMW 5555-060.17 11/10/2009
To becomeAdministered
by RCWD-Spot Repair
GrWX
GsWX
GÈWX
RiceCree
k
Lamprey Pass StateWildlife Refuge
Main
Trunk
Branch 1
Branch 2Pr
ivate
Bran
ch 7
Private
Columbus
Rice CreekWatershed District
ACD 31Repair Report
0 0.25 0.50.125Miles
¶Note: Hydrology reflects current land use. Sources: TLG, RCWD, MN DOT
Anoka County
Outlet Control StructuresFlow DirectionHigh Spots in Open Channel to be Repaired
Private to become publicTo become Administered by RCWD
Public System Outside Existing RCWD Bndry
Public Spot Maintenance to Existing Profile
Repair to As Constructed ProfilePrivate Open Channel - No RepairsPublic Open Channel - No Repairs Wetland Management Corridor à
ààà à
à
àà
à àPotential Wetland Restoration AreasSubwatershedsCounty RoadsColumbus RMP BoundaryRCWD Boundary (2009)State/Local ParksLakes
Anoka
HennepinRamsey
Washington
ProjectLocation Map
Figure A-4 ACD 31 Resource Management Plan Alternative (#4)Scale: Drawn by: Checked by: Project No.: Date: Sheet:AS SHOWN SMW 5555-060.17 8/12/2009
To becomeAdministered
by RCWD-Spot Repair
GrWX
GÈWX
Columbus
Bran
ch 7
Priva
tePrivate
Branch 3
Branc
h 5
Private
Priva
te
Branch 6
Functional Branch
(Not of Record)Branch 1
Branch 1
Branch 2
Branch 2
Main
Trunk
Main Trunk
Main
Trunk
ACD 31Repair Report
Calculated Lateral Drainage Zone
0 1,000 2,000500Feet
¶Sources: TLG, RCWD, MN DOT
Anoka County
Lateral Drainage ZoneLakesPrivate Open Channel - No RepairsRepair to As Constructed ProfileSubwatershedsCounty RoadsColumbus RMP BoundaryRCWD Boundary (2010)
Wetland Type3,4, and 5 Wetland Types
Anoka
Washington
Hennepin
RamseyProject
Location Map
Figure A-5 Calculated Lateral Drainage ZoneScale: Drawn by: Checked by: Project No.: Date: Sheet:AS SHOWN SMW 5555-230 3/17/2015CCO
Est'd Quantity
ExtensionEst'd
Quantity Extension
Est'd Quantity
ExtensionEst'd
Quantity Extension
Public Drainage System InfrastructureMobilization Lump Sum $15,000 0 $0.00 1 $15,000.00 1 $15,000.00 1 $15,000.00 Traffic Control Lump Sum $10,000 0 $0.00 1 $10,000.00 1 $10,000.00 1 $10,000.00 Remove & Dispose of Inplace Culvert Linear Foot $15 0 $0.00 229 $3,435.00 434 $6,510.00 434 $6,510.00 Excavation of Existing Trench Linear Foot $9 0 $0.00 28473 $256,257.00 5263 $47,367.00 5263 $47,367.00 Temporary and Permanent Relocations Lump Sum $5,000 0 $0.00 1 $5,000.00 1 $5,000.00 1 $5,000.00 Tree Clearing Acre $7,500 4.8 $35,898.76 4.8 $35,898.76 4.8 $35,898.76 4.8 $35,898.76 24" GS Apron Each $475 0 $0.00 4 $1,900.00 4 $1,900.00 4 $1,900.00 30" GS Apron Each $750 0 $0.00 6 $4,500.00 10 $7,500.00 10 $7,500.00 36" GS Apron Each $760 0 $0.00 8 $6,080.00 20 $15,200.00 20 $15,200.00 24" HDPE Culvert Linear Foot $60 0 $0.00 58 $3,480.00 58 $3,480.00 58 $3,480.00 30" HDPE Culvert Linear Foot $70 0 $0.00 66 $4,620.00 149 $10,430.00 149 $10,430.00 36" HDPE Culvert Linear Foot $80 0 $0.00 105 $8,400.00 257 $20,560.00 257 $20,560.00 Patch Existing Gravel Surface Lump Sum $300 0 $0.00 8 $2,400.00 13 $3,900.00 13 $3,900.00 Seeding and Mulch Acre $5,000 4.8 $23,932.51 13.1 $65,500.00 5.7 $28,500.00 5.7 $28,500.00
Public Drainage System Infrastructure Subtotal $59,831.00 $422,471.00 $211,246.00 $211,246.00
Land for Infrastructure (Easement and Land Acquisition)Permanent Easement Costs (private ditch consolidation)1 Acre $25,000 10.8 $270,000.00 0 $0.00 9.0 $225,000.00 9.0 $225,000.00
Land for Infrastructure Subtotal $270,000.00 $0.00 $225,000.00 $225,000.00
Public Drainage System Wetland MitigationWetland Mitigation (from Existing Bank) Acre $20,000 0 $0.00 0.0 $0.00 0.0 $0.00 0.0 $0.00
Public Drainage System Natural Resource Mitigation Subtotal $0.00 $0.00 $0.00 $0.00
Infrastructure at Public RoadwaysRemove & Dispose of Inplace Culvert Linear Foot $12 0 $0.00 492 $5,904.00 653 $7,836.00 653 $7,836.00 27"x43"x49' Arch RCP Apron Each $1,500 0 $0.00 2 $3,000.00 0 $0.00 0 $0.00 30" RCP Apron Each $1,300 0 $0.00 2 $2,600.00 2 $2,600.00 2 $2,600.00 48" RCP Apron Each $1,500 0 $0.00 2 $3,000.00 2 $3,000.00 2 $3,000.00 24" GS Apron Each $475 0 $0.00 2 $950.00 2 $950.00 2 $950.00 36" GS Apron Each $760 0 $0.00 6 $4,560.00 10 $7,600.00 10 $7,600.00 24" CMP Culvert Linear Foot $40 0 $0.00 50 $2,000.00 50 $2,000.00 50 $2,000.00 36" CMP Culvert Linear Foot $60 0 $0.00 193 $11,580.00 354 $21,240.00 354 $21,240.00 36" HDPE Culvert Linear Foot $80 0 $0.00 52 $4,160.00 52 $4,160.00 52 $4,160.00 27"x43"x49' Arch RCP Culvert Linear Foot $200 0 $0.00 49 $9,800.00 49 $9,800.00 49 $9,800.00 30" RCP Culvert Linear Foot $120 0 $0.00 24 $2,880.00 24 $2,880.00 24 $2,880.00 48" RCP Culvert Linear Foot $150 0 $0.00 49 $7,350.00 49 $7,350.00 49 $7,350.00 Roadway Repair Each $6,000 0 $0.00 3 $18,000.00 3 $18,000.00 3 $18,000.00 Erosion Control Blanket Cat. 3 Square Yard $4 $0.00 72 $288.00 72 $288.00 72 $288.00
Public Infrastructure (Others) Subtotal $0.00 $76,072.00 $87,704.00 $87,704.00
Engineering/Legal/AdminEngineering/Project Management Dollars $1 38966 $38,966.20 140000 $140,000.00 120000 $120,000.00 120000 $120,000.00 Legal Services Dollars $1 20000 $20,000.00 20000 $20,000.00 20000 $20,000.00 20000 $20,000.00 District Administration Dollars $1 19483 $19,483.00 49854 $49,854.00 41145 $41,145.00 41145 $41,145.00
Engineering/Legal/Admin Subtotal $78,449.20 $209,854.00 $181,145.00 $181,145.00
Contingency Percent 20% $11,966.00 $99,709.00 $59,790.00 $59,790.00
Grand Total $420,246.20 $808,106.00 $764,885.00 $764,885.00
1 Required easement widths are assumed at a 50 foot width along public road rights of way, and 100 foot width elsewhere
Alternative 3Active Agricultural Repair
Alternative(AARA)
Appendix APreliminary Opinion of Probable Construction Cost Details
Unit Price
Alternative 1 Existing System
Conditions (ESCA)
Alternative 4Resource Management Plan
Alternative(RMPA)
Description Units
Alternative 2As-Constructed and
Subsequently Improved Alternative (ACSIA)
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