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Summary Report: 2013 Sampling Results
Addison County Riverwatch Collaborative
24 February 2014
Prepared by:
Kristen Underwood
South Mountain Research & Consulting and
Addison County Riverwatch Collaborative
Prepared for:
Jim Kellogg
VTDEC Water Quality Division
Digital copy of this report available for download at:
www.acrpc.org/acrwc
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TABLE OF CONTENTS
1.0 Introduction ......................................................................................................................... 1
2.0 Background .......................................................................................................................... 1
3.0 Methods ............................................................................................................................... 3
4.0 Precipitation Data ................................................................................................................ 5
5.0 Hydrologic Data.................................................................................................................... 6
6.0 Sample Results ..................................................................................................................... 9
7.0 References ......................................................................................................................... 12
Appendix APhysical Features of Watersheds
Appendix BPrecipitation and Flow Data
Appendix CWater Quality Data Tables by Watershed
Appendix DQA Summary Report
Attachments
1 Lemon Fair River2013 Water Quality Summary2 Lewis Creek2013 Water Quality Summary3 Little Otter Creek2013 Water Quality Summary4 Middlebury River2013 Water Quality Summary5 New Haven River2013 Water Quality Summary6 Otter Creek (Lower)2013 Water Quality Summary
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Table 1. Rotational Schedule for Focused Monitoring
20122013 2014 - 2015 2016 - 2017
Lewis Creek Middlebury River Little Otter CreekLemon Fair Otter Creek New Haven River
Beginning with the 2012 sampling season, Lewis Creek and the Lemon Fair River were selected to be
focus watersheds (Figure 1, watersheds in bold outline). Therefore, rotational sites were scheduled for
sampling in addition to the sentinel sites in these two watersheds. Table 2a displays the schedule of
sampling sites and parameters for the 2013 season; R denotes a rotational site, S for a sentinel site.
A slightly different schedule of sampling parameters is indicated for Spring versus Summer monthsi.e.,
E. coliwas added to the list for Summer events.
3.0 Methods
Water quality samples were collected by ACRWC volunteers in accordance with quality assurance
procedures outlined in the EPA-approved Generic Quality Assurance Project Plan prepared by VTDEC.
A Quality Assurance Summary report for the 2013 sampling data was submitted under separate cover.
Samples were delivered to the LaRosa Analytical Laboratory housed in the Hills Building in the University
of Vermont campus in Burlington, Vermont.
During 2013, ACRWC volunteers collected grab samples at 31 sites in these six watersheds during twoSpring events (April and May) and four Summer events (June, July, August and September). Sampling
dates were pre-determined as the first Wednesday of each month (except July to avoid the 4th
of July
holiday), and were not designed to capture any specific flow condition:
April 3 May 1 June 5 July 10 August 7 September 4
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Table 2. 2013 Schedule of Sites / Parameters Spring and Summer
Project Name: Addison County River Watch Collaborative
Type River Name Site ID Site Location TP DP TN Turbidity TSS E.c ol i A L K TP DP TN Turbidi ty TSS
S Lewis Creek LCR3.7 Old Route 7 Bridge X X X X X X X
R Lewis Creek LCR9.9 Upper Covered Bridge, Roscoe Rd. X X X X
S Lewis Creek LCR14 Tyler Bridge X X X X X X X
R Lewis Creek LCR17.2 Starksboro Ballfields X X X X
R Lewis Creek LCR18.6 Lewis Creek Farm footbridge X X X X
R Lewis Creek LCR19.5 Parsonage Road bridge X X X X X X
R Lewis Creek LCR27.8 Hillsboro Road X X X X X X
R Pond Brook LCT3D.5 Silver Street culvert X X X X X X X
O Highknob Brook HK-0.8 Above Freedom Access Road X X X X
O Hillsboro Brook HLB-0.8 Below Hillsboro Rd & confluence of two t ribs X X X X
O Hogback Brook HGB-1.7 Near Parsonage Road X X X X
O Hollow Brook HLW-2.5 Off of Hollow Rd X X X X
O Lewis Creek LCR26.5 Above Gorge X X X X
O Pringle Brook PRG-0.3 Below falls off Spear St Ext X X X X
R Lemon Fair River LFR0 Weybridge Road bridge X X X X X X X X X X X
R Lemon Fair River LFR1.2 Prunier Road bridge X X X X X X X X X X X
S Lemon Fair River LFR6.7 Route 125 bridge. X X X X X X X X X X X
S Lemon Fair River LFR12 Downstream of Route 74 bridge X X X X X X X X X X X
R Lemon Fair River LFR15.8 Shacksboro Road bridge X X X X X X X X X X X
R Lemon Fair River LFR23.9 Murray Road Bridge X X X X X X X X X X X
R Beaver Branch LFB2.5 Sperry Road crossing, Beaver Branch X X X X X X X X X X X
R Trib to Beaver Branch LFBS1-0.9 Route 125 crossing, trib to Beaver Branch X X X X X X X X X X X
S Little Otter Creek LOC4.3 Route 7 Bridge X X X X X X X X X
S Mud Creek MDC1.2 Wing Rd./Middlebrook Rd. (South) X X X X X X X X X
S Middlebury River MIR1.5 Shard Villa Rd. Bridge X X X X X
S Middlebury River MIR5.7 Midd. Gorge @ Rte 125 Bridge X X X X X
S New Haven River NHR2 Muddy Branch confluence (just below) X X X X X
S New Haven River NHR9 South St. Bridge X X X X X
S New Haven River NHR11.5 Bartlett's Falls Pool X
S Otter Creek OTR18 Twin Bridges Picnic Area X X X X X X X
S Otter Creek OTR7.3 Vergennes Falls/below outfall X X X X X X X
Project Number: 137-01
Sample Year: 2013
Summer Schedule (Jun, Jul, Aug, Sep)
PARAMETERS
Spring Schedule (Apr, May)
Site Types: R = Rotational; S = Sentinel; O = Other (special project).
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4.0 Precipitation Data
Precipitation data were compiled from existing weather stations in vicinity of the ACRWC watersheds
(Table B-1). Calendar year 2013 was a wetter-than-normal year, as recorded at regional weather
stations in South Burlington (Airport) and South Lincoln, Vermont, and a somewhat drier-than-normal
year in Rutland. Heavy rainfall in the months of May, June, and July contributed to the greater-than-
normal annual precipitation in Addison and Chittenden Counties; precipitation in other months was
near, or even below, normal.
Similar to the previous year, snowfall in the winter of 20122013 was less than normal as recorded at
the South Lincoln and Rutland weather stations (Table B-2). Snowfall recorded at the Burlington airport
was near normal.
Based on USGS provisional real-time gaging records, ice-out in the lower Lewis Creek and New Haven
River watersheds and at the Otter Creek Middlebury station occurred in late February. There were a
couple of temporary ice-out events in mid- and late-January on the New Haven River and Otter Creek
associated with mid-winter thaws. Ice-out on the lower Little Otter Creek occurred in mid-March.
While the rainfall amounts over the year were greater than normal, there were no major storm events,
with the exception of mid-May flooding and early July flooding that more significantly affected our
neighbors to the north and east.
Heavy rains beginning on May 23 were generated from training showers and thunderstorms andcontributed to higher-than-normal rainfall amounts for May in our Addison County watersheds.
Communities to the north and east in Chittenden and Lamoille Counties sustained damagesfrom flash flooding (NCDC, 2014).
May, Junepersistent rains from stalled weather patterns led to record rainfall amounts in Mayand June, and record-setting high-stages of Lake Champlain in early July1.
July 3, July 4Showers and thunderstorms developed in tropical moisture feeding along astationary boundary. Soils were saturated from May and June rains, a condition which
contributed to flooding. Flash flooding particularly impacted Granville and Waitsfield just over
the mountains to the east of our ACRWC watersheds (NCDC, 2014).
July 9, 10 - Southerly deep layer flow in the atmosphere provided a feed for abundant tropicalmoisture from the Gulf of Mexico to the northeast. Training showers and thunderstorms led toflash flooding in portions of the upper Otter Creek basin (NCDC, 2014).
1http://vtdigger.org/2013/07/14/facing-climate-change-record-summer-rainfall-flooding-of-lake-champlain-
caused-by-instability-of-jet-stream/
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5.0 Hydrologic Data
Flow data were compiled from available USGS gaging stations in vicinity of the ACRWC watersheds. Four
of the six watersheds sampled by the ACRWC have USGS gaging stations which record instantaneous
flow at fifteen minute intervals. Gages on Lewis Creek, Little Otter Creek, and New Haven River are nearthe downstream end of the main stem. A nearby gage on Otter Creek (at Middlebury) is located mid-
basin, at 66.5 % of this 944 square mile basin.
Flow records are available for the past 23 years at Little Otter Creek, New Haven River, and Lewis Creek
gaging stations. Mean annual flows recorded at these stations over that time period are summarized in
Table 5, along with data from the Otter Creek at Middlebury station. Data are summarized by water
yearwhich begins October 1st
of the previous calendar year and extends through September 30th
of
the indicated year. Based on 23 years of record, mean annual flows in these ACRWC watersheds for
water year 2013 were near normal.
Table 5. Mean Annual Flows, 1991 2013, ACRWC watersheds.
Watershed
Drainage Area (sq mi) 73 116 81 944
Gaged Area (sq mi) 57.1 115 77.2 628
Min (1991-2013) 2002 27 1995 129 1995 54 1995 672
Max (1991-2013) 2011 145 2011 378 2011 214 2011 1912
Mean (1991-2013) 67 220 109 1167Water Year 2013 70.1 253 N/A N/A
Little Otter
Creek
New Haven
River Lewis Creek
Otter Creek at
Middlebury
Source: USGS, 2014, on-line surface water data, .
Note:As of report publication, 2013 data for Lewis Creek and Otter Creek stations were still provisional.
Figure 2 presents mean daily flows in the Little Otter Creek, New Haven River and Lewis Creek. Flows
have been normalized to gaged drainage area. Generally, New Haven River tends to exhibit more flashy
flows, and often has a somewhat higher flow per unit area than the Lewis Creek and Little Otter Creek.
While the average yearly flows in the ACRWC watersheds were near normal in 2013, monthly flowswere above normal from late May to early July. Peak flows for water year 2013 occurred in late May in
the New Haven River, Lewis Creek, and Little Otter Creek, associated with the May 22 and 26 storms.
Peak flow at the Otter Creek at Middlebury station occurred on July 11 in response to the July 3-4
storms. Still, peak flows for the year were less than the estimated 2-year storm (Q2) (Olson, 2002) at
each gaging station.
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0
10
20
30
NormalizedFlow
(cfs/sqm
i)
Measurement Date
Water Year 2013, Daily Mean Flow Normalized to Drainage Area
New Haven River
Lewis Creek
Little Otter Creek
Otter Creek, MB
4/3
5/1 6/57/10
8/7approx.Ice Out
Snowpack somewhatless than normal.
9/4
Note: Data for Lewis Creek and Otter-Middlebury are provisional as of
24 Februray 2014, and not estimated forice-affected times during Jan & Feb 2013.
Figure 2. ACRWC Scheduled Spring and Summer Sampling Dates in 2013
relative to Mean Daily Flows normalized to Gaged Drainage Area.Note: As of 24 February 2014, daily mean flow data posted on the USGS web page for Lewis Creek and Otter Creek @ Middlebury are provisional,
and estimates have not been made for ice-affected portions of the flow record in January and February 2013.
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1
100
10000
0 10 20 30 40 50 60 70 80 90 100
Discharge(cfs)(DailyMeanFlow)
Percent of time that indicated discharge was equaled or exceeded(Flow Duration Interval, %)
Flow Duration Curve (Log Intervals) for Lewis Creek at North Ferrisburg, VTWater Years: 1991 - 2011 (USGS Stn# 04282780, 77.2 sq mi )
80 cfs
48 cfs
17 cfs
HighFlows
MoistConditions
Mid-rangeFlows
DryConditions
LowFlows
237 cfs
4/3/2013, 96 cfs6/5/2013, 86 cfs7/10/2013, 135 cfs
8/7/2013, 30 cfs9/4/2013, 34 cfs
5/1/2013, 72 cfs
Figure 3. ACRWC Scheduled Spring and Summer Sampling Dates in 2013
relative to Flow Duration Curve for the Lewis Creek watershed (after EPA, 2007)
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Figure 3 presents a flow duration curve for the Lewis Creek watershed, annotated with the 2013 season
sample dates. Spring sampling dates (April 3, May 1) coincided with moderate stages in area rivers
associated with spring rains and snow melt. Summer sampling dates coincided with low- to base-flow
conditions (August 7 and September 4) except for the July 10 event which followed the July 3-4 storms.
and the June 5 event when flows were somewhat elevated due to high May and June rainfall. These
storms were not as significant across Addison County as they were in Chittenden County to the north
and Rutland County to the south. No spring runoff events or significant high-flow events were captured
during the 2013 season.
6.0 Sample Results
Appendix C contains quality-assured sample results for the 2013 season for the ACRWC watersheds.
Attachments 1 through 6 summarize these results on a single page for each watershed. These
attachments have been designed to serve as a handout for use in future outreach events to watershed
stakeholders and relevant town boards. As discussed in Section 2.0, the Lemon Fair River and Lewis
Creek were chosen as focus watersheds for 2013. Therefore, sample results are presented for sentinel
as well as rotational sites in these watersheds.
In general, water quality results for 2013 were consistent with historic results and trends summarized in
the 2009 Draft Water Quality Reports for each watershed (Hoadley, 2009). E.colicounts in each river
exceeded the VT Water Quality Standard (VWQS) of 77 organisms/ 100 mL at one or more stations
during one or more summer sampling dates. Generally, elevated E.colidetections were associated with
developed land uses including nearby agriculture and livestock with direct access to the river. Wildlife
sources of E.colialso exist in these rivers, including beaver, deer, and waterfowl. E.colicounts were
below the federal health-based standard (235 organisms/100 mL) at popular swimming sites. E.coli
counts tended to be higher during low-flow events. A similar occurrence of elevated E. coli counts was
noted during low flows in 2012 and in historic drought yearse.g., 1993 and 1995. A few elevated
counts of E.coli were reported for the July 10 event on the receding limb from high flows generated by
July 3-4 rains: at Tyler Bridge in the Lewis Creek (LCR14), along Beaver Brook tributary to the Lemon
Fair, and on the lower Middlebury River (MIR1.5). Each of these stations is downstream of agricultural
activity and downstream of documented beaver dams. The Vermont Agency of Natural Resources has
published EPA-approved Total Maximum Daily Load (TMDL) plans for the Lewis Creek (and Pond Brook),
Little Otter Creek, Middlebury River, and Otter Creek (VTDEC, 2011). These TMDL plans include
recommendations for further assessment and mitigation of E.colisources in these waters.
Turbidity concentrations in the ACRWC watersheds vary, in part depending on geologic setting and flow
stage. In the mountainous watersheds of Lewis Creek, Middlebury River, and New Haven River (shaded
yellow in Table A-1), turbidity tends to exceed the standard of 10 NTUs during high flows. Since no
major storm events were captured during the regularly-scheduled monthly sampling, turbidity did not
exceed the standard in these mountainous watersheds, except slightly on one occasion in the lower
Lewis Creek watershed at station LCR3.7 near the Route 7 bridge crossing. A concentration of 10.9 NTUs
was reported for the July 10 sample from this station, in the days following significant rains on July 3-4.
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In the valley watersheds (Little Otter Creek and Lemon Fair, shaded light blue in Table A-1), the turbidity
standard (10 NTUs for the designated cold-water fishery of Little Otter and 25 NTUs for the warm-water
fishery of Lemon Fair) tends to be exceeded on a more frequent basis, independent of flow condition. In
2013, turbidity at select stations in these valley watersheds exceeded the VWQS during each of the
sampling events, except April 3 in the Little Otter Creek when soils were still somewhat frozen. As
noted in Table A-1 the valley watersheds have a much higher percentage of silt / clay soils derived from
glacial lake sediments, which contributes to the higher turbidity in these rivers. The Otter Creek
represents a mixed water with contributions from both the mountainous and valley watersheds. During
2013, the turbidity standard (25 NTUs) at the sentinel stations on Otter Creek was not exceeded on the
sample dates.
Phosphorus is monitored in the Addison County watersheds with respect to two main objectives. First,
total phosphorus concentrations are compared to proposed instream nutrient criteria (VTDEC WQD,
2009) to identify potential impacts to Aquatic Life Support and Aesthetics uses of these waters.
Elevated phosphorus can lead to enhanced algae production and other changes in water quality that
reduce the rivers capacityto support macroinvertebrates, fish and other aquatic organisms. These
changes also have the potential to impact aesthetics and recreational uses of these waters. VTANR
recommends that the mean of at least three low-flow phosphorus concentrations collected on non-
consecutive days is compared to the relevant proposed phosphorus criterion2. Only two of the Summer
sampling events from 2013 could be classified as low flow: August 7 and September 4 (see Figure 3).
Phosphorus concentrations in the mountainous watersheds (New Haven, Middlebury) did not exceed
the proposed instream phosphorus criteria. The same was true for most of the Lewis Creek stations,
except for the Pond Brook sentinel station (LCT3D.5) and a new station on the Pringle Brook in the lower
watershed, where mean total phosphorus concentrations exceeded the proposed criterion of 44 ug/L
for the warm-water medium gradient (WWMG) wadeable stream ecotype for a Class B water. Mean
low-flow concentrations of phosphorus in the valley watersheds exceeded the proposed instream
phosphorus criteriaboth sentinel stations on the Little Otter Creek and seven of the eight stations
monitored on Lemon Fair. Mean phosphorus concentrations at the Otter Creek sentinel stations did
not exceed the instream nutrient criterion.
A second reason to monitor for phosphorus at the subwatershed level in Addison County watersheds is
to evaluate relative contributions of phosphorus to Lake Champlain. Each of the watersheds monitored
by the Collaborative contributes significant phosphorus to the lake, either directly (Lewis Creek, Little
Otter Creek) or via Otter Creek (Middlebury River, New Haven River, Lemon Fair). The most substantial
loading occurs during high flow eventsgenerally occurring in the spring or fall months. In 2010 and
2011, the Collaborative carried out a flow / loading study in the Little Otter Creek. A similar study was
completed in 2012 on the Pond Brook tributary of Lewis Creek. Results are reported separately. Stream
2Within this context, VTANR defines low flow as the median monthly flow for that month having the lowest
median monthly (LMM) flow. This definition differs somewhat from the Low Flows presented in the context of a
Flow Duration Curve (after EPA, 2007). For example, the LMM for Lewis Creek has been calculated by Blaine
Hastings of VTANR as 21.2 cfs (September) - which is slightly above the range of flows presented as Low Flows in
Figure 3.
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flow and water quality monitoring data have been used to inform and develop priority implementation
projects on a sub-watershed scale. Coarse estimates of phosphorus yields from each sub-watershed
were used to communicate land use impacts on water quality and encourage landowner and municipal
participation. In cooperation with local, state and federal partners, projects were prioritized and (with
landowner willingness) will be developed to achieve reductions in phosphorus and sediment loading
from these catchments. Identified projects have included wetland restoration & conservation, livestock
exclusion, riparian buffer plantings, alternate tillage and crop rotation practices, gully stabilization,
improved forest management techniques, and improved road maintenance practices.
Nitrogen was monitored in three of the Addison County watersheds in 2013: Lemon Fair River, Otter
Creek, and Lewis Creek. None of the detected concentrations exceeded the VWQS of 5 mg/L for
nitrogen as nitrate. However, the mean concentration of total nitrogen for the two available low-flow
summer sample dates exceeded the proposed instream nitrogen criteria (0.75 mg/L) at four of the eight
Lemon Fair sites and forone out of the ten Lewis Creek watershed stations sampled for Nitrogen.
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7.0 References
Olson, Scott A., 2002, Flow-Frequency Characteristics of Vermont Streams. USGS Water-Resources
Investigations Report 02-4238.
National Climatic Data Center, 2014, Event Narratives for Flood Events in Addison County, Vermont,
accessed on 12 January 2014 at: http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwEvent~storms
NOAA National Weather Service Recent Weather Event Summaries, 2014, Heavy Rainfall and
Associated Flooding Event on 23 May 2013 accessed on 12 January 2014 at:
http://www.erh.noaa.gov/btv/events/2013May23/2013May23_Flooding.pdf
NOAA Online Weather Data: Daily Almanac accessed in January 2014 at:
http://www.weather.gov/climate/xmacis.php?wfo=btv
USGS, 2014, on-line surface water data, .
VTDEC, 2011, Vermont Statewide Total Maximum Daily Load (TMDL) for Bacteria Impaired Waters,
prepared by FB Environmental Associates, Inc., Portland, ME. Including Appendices 2, 3, 4, 5 and 6.
VTDEC Water Quality Division, 2009 (August 18), Proposed Nutrient Criteriafor Vermonts Lakes and
Wadeable Streams. http://www.anr.state.vt.us/dec/waterq/lakes/docs/lp_2009nutrientcriteria.pdf
Vermont Natural Resources Board, 2008. Vermont Water Quality Standards.
Effective January 1, 2008. Montpelier, VT. http://www.nrb.state.vt.us/wrp/rules.htm
http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwEvent~stormshttp://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwEvent~stormshttp://www.erh.noaa.gov/btv/events/2013May23/2013May23_Flooding.pdfhttp://www.erh.noaa.gov/btv/events/2013May23/2013May23_Flooding.pdfhttp://www.weather.gov/climate/xmacis.php?wfo=btvhttp://www.weather.gov/climate/xmacis.php?wfo=btvhttp://waterdata.usgs.gov/vt/nwishttp://waterdata.usgs.gov/vt/nwishttp://www.anr.state.vt.us/dec/waterq/lakes/docs/lp_2009nutrientcriteria.pdfhttp://www.anr.state.vt.us/dec/waterq/lakes/docs/lp_2009nutrientcriteria.pdfhttp://www.nrb.state.vt.us/wrp/rules.htmhttp://www.nrb.state.vt.us/wrp/rules.htmhttp://www.nrb.state.vt.us/wrp/rules.htmhttp://www.anr.state.vt.us/dec/waterq/lakes/docs/lp_2009nutrientcriteria.pdfhttp://waterdata.usgs.gov/vt/nwishttp://www.weather.gov/climate/xmacis.php?wfo=btvhttp://www.erh.noaa.gov/btv/events/2013May23/2013May23_Flooding.pdfhttp://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwEvent~storms -
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Appendix A
Physical Features of Watersheds
Monitored by Addison County Riverwatch Collaborative
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Table A-1 summarizes the physical characteristics of the ACRWC watersheds and nearby LaPlatte River.
A majority of the drainage area for the New Haven River and Middlebury River is positioned in the
mountainous terrain of the Northern Green Mountain physiographic province. Lewis Creek also has a
significant percentage of its drainage area in this province. LaPlatte River, Little Otter Creek and Lemon
Fair River are located further to the west in the broad, low-relief, Champlain Valley physiographic
province. Thus, topographic relief and overall gradients of the New Haven River, Middlebury River and
Lewis Creek are substantially higher than that of the Champlain Valley watersheds.
The Green Mountain watersheds (New Haven River, Middlebury River, and Lewis Creek; shaded yellow
in Table A-1) tend to exhibit flashier flows, than the Champlain Valley watersheds due, in part, to the
steeper overall gradients. The lower-gradient watersheds of the Champlain Valley (shaded blue in Table
A-1) tend to be characterized by higher percentages of hydric soils derived from lacustrine and marine
lake sediments, and have higher percentages of wetlands. These conditions offer temporary surface
water storage and lagged flows, resulting in broader, lower-magnitude storm peaks, longer times to
peak, and gradual hydrograph recessions.
In general, the Green Mountain watersheds tend to have higher percentages of forest cover, while the
Champlain Valley watersheds have higher percentages of agricultural land use.
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Table A-1. Physical Features of Watersheds.
Soils (2) Stream
(% Lake % Hydric % Wetlands Relief Gradient Classification
NGM CV Sediments) Soils (VSWI) (ft) (ft / mile) Forest Agric Urban (Class B) (3)
Middlebury River Cold Water
63 sq mi 71% 29% 10% 15.2% 3.2% 1,758 111 81% 11% 3% Fish
New Haven River Cold Water
116 sq mi 63% 37% 14% 9.8% 2.5% 2,720 106 76% 15% 4% Fish
Lewis Creek Cold Water
81 sq mi 31% 69% 24% 18.6% 6.5% 1,676 52 60% 26% 5% Fish
LaPlatte River Warm Water
53 sq mi 5% 95% 45% 25.3% 6.1% 960 49 38% 39% 16% Fish
Little Otter Creek Cold Water
73 sq mi -- 100% 62% 30.3% 9.7% 416 18 35% 45% 4% Fish
Lemon Fair River Warm Water
91 sq mi -- 91% 63% 19.3% 7.3% 256 8 25% 63% 6% Fish
Lower Otter Creek Warm Water
498 sq mi 29% 69% 38% 20.8% 8.9% NM NM 67% 21% 6% Fish
(of 944 sq mi basin)
o es:
(1)
(2) Soils of glaciolacustrine parent material, Natural Resource Conservation Service County Soil Survey Data.
(3) As per VT Water Quality Standards, effective Jan 1, 2008.
NGM = Northern Green Mountains; CV = Champlain Valley; geologic province after Stewart & MacClintock (1969) or biophysical province after the
VT Biodiversity Project.
Watershed Physical Characteristics
Province (1 )
Geologic
Land Use
Major Land Cover/Topography
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Appendix B
Precipitation and Flow Data
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Table B-1. Monthly / Annual Precipitation at climate stations located in vicinity of Addison County.
Data Time
Source Period Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual
Burlington, VT (Airport) 1 1971-2000 2.22 1.67 2.32 2.88 3.32 3.43 3.97 4.01 3.83 3.12 3.06 2.22 36.05
2 1981-2010 2.05 1.76 2.21 2.82 3.45 3.69 4.15 3.91 3.64 3.60 3.12 2.37 36.77
330 ft amsl 2 2009 1.76 1.81 1.90 1.86 5.25 5.25 4.62 2.32 3.67 2.98 2.98 3.02 37.4220 miles N 2 2010 2.41 2.13 2.85 3.08 1.52 5.87 2.25 3.51 4.17 6.24 3.10 3.60 40.73
2 2011 1.44 3.02 3.39 7.88 8.67 3.52 3.68 6.11 6.06 3.49 1.43 2.23 50.92
2 2012 1.96 0.89 0.98 2.84 4.41 3.22 3.78 2.92 5.36 5.04 1.24 3.30 35.94
2 2013 1.11 1.32 2.05 2.05 8.74 9.86 4.49 3.07 4.74 2.59 2.43 2.54 44.99
South Lincoln, VT 1 1971-2000 2.92 2.10 3.14 4.20 4.31 4.58 4.24 5.22 4.44 4.39 3.98 3.13 46.65
2 1981-2010 2.81 2.27 3.12 3.71 4.24 4.75 4.83 5.11 4.13 5.02 3.99 3.41 47.39
1,370 ft amsl 2 2009 3.05 2.91 2.14 2.55 8.71 5.52 9.07 3.03 2.25 4.52 4.76 3.80 52.31
13.6 miles SE 2 2010 2.88 3.69 4.65 4.17 2.21 7.50 7.18 5.61 3.36 11.56 2.13 3.08 58.02
2 2011 1.26 2.04 4.04 1.23 3.95 1.22 2.06 10.71 1.66 1.09 2.19 2.83 34.28
2 2012 2.19 0.83 1.90 3.64 6.29 3.12 2.88 4.77 4.94 7.02 1.38 3.92 42.88
2 2013 1.79 1.44 2.78 2.40 6.33 9.90 8.02 5.54 4.47 2.86 4.15 3.75 53.43
Rutland, VT 1 1971-2000 2.70 1.97 2.59 2.80 3.52 3.85 4.58 4.18 3.91 3.21 3.08 2.73 39.12
2 1981-2010 2.44 2.15 2.77 2.88 3.71 4.00 4.77 4.10 3.78 3.83 3.25 2.96 40.64
620 ft amsl 2 2009 2.29 1.98 2.04 1.96 4.43 3.86 9.30 7.71 2.27 4.76 3.64 3.00 47.2440 miles SSE 2 2010 2.22 2.83 4.69 3.04 2.87 3.00 5.35 4.14 1.95 9.76 2.28 3.66 45.79
2 2011 2.93 3.76 3.61 5.69 4.40 4.38 4.88 11.24 4.88 3.48 1.29 2.80 53.34
2 2012 1.69 0.69 1.12 3.32 5.26 3.66 3.62 3.42 4.58 4.57 0.71 4.08 36.72
2 2013 1.85 0.78 1.51 2.58 5.60 5.93 5.59 3.30 3.25 1.36 2.58 2.50 36.83
Total precipitation in inches, including liquid equivalent of snow, sleet.
Values for 1971-2000 and 1981-2010 periods reflect averages for the time period. Values for individual years are totals.
Data Sources: 1 National Climatic Data Center, 2002, Climatography of the United States No. 81 - 43 (Vermont), Monthly S tation Normals of
Temperature, Precipitation, and Heating and Cooling Degree Days: 1971-2000
2 NOAA Online Weather Data, http://www.weather.gov/climate/index.php?wfo=btv
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Table B-2. Monthly / Seasonal Snowfall Totals at climate stations located in vicinity of Addison County.
Time
Period Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Season
So. Burlington, VT 1971-2000 0.0 0.0 0.0 0.3 7.2 17.1 20.9 15.3 15.4 5.8 0.0 0.0 81.9
1981-2011 0.0 0.0 0.0 0.3 5.1 19.1 21.9 16.9 15.6 4.6 0.0 0.0 83.6(Airport) 2009-2010 0.0 0.0 0.0 0.0 0.0 17.7 48.4 24.0 0.9 5.5 0.0 0.0 96.5
2010-2011 0.0 0.0 0.0 0.1 0.3 27.9 26.9 43.1 29.3 0.8 0.0 0.0 128.4
2011-2012 0.0 0.0 0.0 0.1 5.0 6.9 13.4 6.4 5.9 0.0 0.0 0.0 37.7
2012-2013 0.0 0.0 0.0 0.0 3.8 30.7 14.6 16.6 16.2 1.0 0.0 0.0 82.9
South Lincoln, VT 1981-2000 0.0 0.0 0.0 2.2 13.9 26.9 29.6 22.8 24.5 10.5 0.7 0.0 131.1
1981-2011 0.0 0.0 0.0 2.3 11.4 28.6 27.3 24.0 21.5 9.4 0.6 0.0 125.0
2009-2010 0.0 0.0 0.0 0.1 1.1 26.0 22.5 33.0 3.2 10.0 1.0 0.0 96.9
2010-2011 0.0 0.0 0.0 2.2 4.0 39.5 42.3 40.2 26.2 1.8 0.0 0.0 156.2
2011-2012 0.0 0.0 0.0 2.4 4.9 24.3 18.4 12.0 11.6 0.0 0.0 0.0 73.6
2012-2013 0.0 0.0 0.0 0.0 4.8 25.8 14.4 11.9 21.3 1.3 0.0 0.0 79.5
Rutland, VT 1971-2000 0.0 0.0 0.0 0.3 5.6 13.5 16.7 13.9 12.4 3.6 0.0 0.0 66.0
1981-2011 0.0 0.0 0.0 0.5 4.4 16.7 17.3 14.7 12.6 3.3 0.0 0.0 69.3
2009-2010 0.0 0.0 0.0 0.0 0.0 18.2 15.9 19.9 0.1 2.1 0.0 0.0 56.2
2010-2011 0.0 0.0 0.0 0.0 0.9 21.3 26.8 37.2 14.6 0.9 0.0 0.0 101.7
2011-2012 0.0 0.0 0.0 6.5 2.9 5.0 8.9 2.7 4.2 0.0 0.0 0.0 30.2
2012-2013 0.0 0.0 0.0 0.0 0.4 23.9 8.1 8.5 10.9 0.2 0.0 0.0 52.0
Total snowfall in inches. Values for 1971-2000 and 1981-2011 periods reflect averages for the time period. Values for seasons are totals.
Source: http://www.weather.gov/climate/xmacis.php?wfo=btv data available as of Jan 2014
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Table B-3. Flows recorded in Addison County rivers, 2013
River Lit tle Otter Ck Lewis Creek New Haven River Otter Ck MB
USGS Gage # #04282650 #04282780 #04282525 #04282500
Drainage Area (sq mi) 57.1 77.4 115 630
Sample Dates 4/3/2013 50 96 170 1,310
(Daily Mean Flows) 5/1/2013 24 72 185 1,660
(cfs) 6/5/2013 44 86 197 1,960
7/10/2013 78 135 371 3,130
8/7/2013 9.0 30 97 627
9/4/2013 11 34 117 751
Peak Flows Q2 1,120 2,280 4,410 4,270
(Olson, 2002; Table 2) Q5 1,640 2,990 6,980 5,840
Q10 1,990 3,420 8,870 6,970
Q25 2,440 3,920 11,500 8,480
Q50 2,790 4,270 13,500 9,680
Q100 3,130 4,590 15,700 10,900
Q500 3,950 5,290 21,200 14,200
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Appendix C
Water Quality Data Tables by Watershed
Abbreviations:
TN = Total NitrogenTP = Total Phosphorus
DP = Dissolved Phosphorus
TSS = Total Suspended Sediments
mpn/100 mL = organisms per 100 milliliters
mg/L = milligrams per liter
ug/ L = micrograms per liter
NTU = Nephelometric Turbidity Units
-- = No Data
NS = Not SampledNA = Not Analyzed (e.g., insufficient sample volume; vial broken in transit)
NM = Not Measured
J = estimated value; constituent was present in an associated field blank at our very slightly
above the method detection limit
Note: QA/QC issues further detailed in separate QA Summary Report
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Lemon Fair River
Location DateE. Coli.
(mpn/100ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
LFR0 4/3/2013 0.45 54.3 20.7 15.3 25.3
LFR1.2 4/3/2013 0.46 53.9 20.1 15.7 26.2
LFR6.7 4/3/2013 0.52 65.4 22.1 19.5 33.5
LFR12 4/3/2013 0.47 48.1 19 7.9 21.8
LFR15.8 4/3/2013 0.47 50.1 18.2 10.6 24.6
LFR23.9 4/3/2013 0.34 42.7 13.6 6.6 14.7
LFB2.5 4/3/2013 0.3 23.8 12.2 5.3 8.36
LFBS1-0.9 4/3/2013 0.37 14.5 9.89 1.1 2.19
LFR0 5/1/2013 0.54 94.9 26.4 49 61.5
LFR1.2 5/1/2013 0.45 102 29.1 56.2 72.3
LFR6.7 5/1/2013 0.55 97.7 25.1 52.6 52.4
LFR12 5/1/2013 0.48 86.9 22.7 41.6 54.5
LFR15.8 5/1/2013 0.46 57.3 17.6 18.2 30.7
LFR23.9 5/1/2013 0.21 27.1 13.6 10.6 9.73
LFB2.5 5/1/2013 0.2 28.8 13 11.8 6.41
LFBS1-0.9 5/1/2013 0.21 19.8 14.2 2.53 2.05
LFR0 6/5/2013 138 1.1 189 115 25.4 J 43.8 J
LFR1.2 6/5/2013 107 1.02 179 112 26 J 45.4 J
LFR6.7 6/5/2013 142 0.94 168 51.1 68.4 J 96.4 J
LFR12 6/5/2013 128 0.73 180 52.6 105 J 136 J
LFR15.8 6/5/2013 112 0.81 79.4 40.6 15.2 J 37.2 J
LFR23.9 6/5/2013 113 0.42 42 23.1 9.71 J 11.7 J
LFB2.5 6/5/2013 345 0.43 54 21.8 17 J 20.1 J
LFBS1-0.9 6/5/2013 119 0.33 34.4 24.9 1.59 J 2.53 J
Shaded cells represent values that exceed the relevant VT Water Quality Standard:
E.coli = 77 MPN/100 mL; Turbidity (warm water Class B) = 25 NTUs
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Lemon Fair River (continued)
Location Date
E. Coli.
(mpn/100ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
LFR0 7/10/2013 21 0.95 317 264 6.5 5.54
LFR1.2 7/10/2013 15 0.97 351 264 6 6.12
LFR6.7 7/10/2013 96 1.19 460 212 22.5 25.9
LFR12 7/10/2013 365 0.93 280 184 55.1 92.1
LFR15.8 7/10/2013 86 0.89 244 181 24.8 56.9
LFR23.9 7/10/2013 152 0.53 73.4 60.3 4.34 7.39
LFB2.5 7/10/2013 649 0.5 81 35.6 28.4 24.5
LFBS1-0.9 7/10/2013 517 0.4 73.6 52.4 4.86 4.98
LFR0 8/7/2013 261 1.13 218 74 88.7 92.1
LFR1.2 8/7/2013 61 1.15 224 68.3 112 131
LFR6.7 8/7/2013 548 1.01 222 60.9 128 136
LFR12 8/7/2013 38 0.71 164 79 65.7 83.6
LFR15.8 8/7/2013 37 0.71 135 104 10.2 26.8
LFR23.9 8/7/2013 20 0.39 23.2 14 5.23 6.77
LFB2.5 8/7/2013 238 0.41 56.8 20.7 35.6 29
LFBS1-0.9 8/7/2013 61 0.56 77.6 38.7 24.6 23.7
LFR0 9/4/2013 131 0.58 66.5 23.3 23.8 24.8
LFR1.2 9/4/2013 91 0.96 272 42.8 106 121
LFR6.7 9/4/2013 770 0.71 138 49.5 58.8 92.8
LFR12 9/4/2013 111 0.62 132 46.5 56.5 80.3
LFR15.8 9/4/2013 102 0.69 114 74.4 11.6 24.6
LFR23.9 9/4/2013 72 0.55 38.8 18.9 10.2 11.2
LFB2.5 9/4/2013 214 0.39 74 26.8 50.8 37.4
LFBS1-0.9 9/4/2013 1553 0.98 107 66.7 16.8 16.6
Shaded cells represent values that exceed the relevant VT Water Quality Standard:
E.coli = 77 MPN/100 mL; Turbidity (warm water Class B) = 25 NTUs
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Lewis Creek
Location Date
Alkalinity
(mg
CaCO3/L)
E. Coli.
(mpn/100
ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
LCR3.7 4/3/2013 20.5 5.1
LCR9.9 4/3/2013 23.7 5.72
LCR14 4/3/2013 15.4 2.24
LCR17.2 4/3/2013 8.68 0.47
LCR18.6 4/3/2013 7.42 0.7
LCR19.5 4/3/2013 7.45 0.46
LCR27.8 4/3/2013 < 5 0.41
LCT3D.5 4/3/2013 28.3 3.65
LCR3.7 5/1/2013 23.7 3.12
LCR9.9 5/1/2013 26.7 3.03
LCR14 5/1/2013 12.3 0.97
LCR17.2 5/1/2013 8.34 0.4
LCR18.6 5/1/2013 7.07 0.37
LCR19.5 5/1/2013 7.27 0.53
LCR27.8 5/1/2013 < 5 0.52
LCT3D.5 5/1/2013 58.2 1.92
LCR3.7 6/5/2013 45 0.45 41.8 5.59
LCR9.9 6/5/2013 52.3 4.94
LCR14 6/5/2013 130 0.61 38.7 1.61
LCR17.2 6/5/2013 10.9 0.54LCR18.6 6/5/2013 9.3 0.31
LCR19.5 6/5/2013 0.54 10.2 0.33
LCR27.8 6/5/2013 0.17 6.81 0.26
LCT3D.5 6/5/2013 102 0.55 109 5.51
HK-0.8 6/5/2013 0.33 8.93 0.52
HLB-0.8 6/5/2013 0.16 8.51 1.37
HGB-1.7 6/5/2013 0.22 9.44 0.35
HLW-2.5 6/5/2013 0.25 9.54 0.56
LCR26.5 6/5/2013 0.18 6.39 0.3
PRG-0.3 6/5/2013 0.54 38.8 2.19
Shaded cells represent values that exceed the relevant VT Water Quality Standard:
E.coli = 77 MPN/100 mL; Turbidity (cold water Class B) = 10 NTUs
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Lewis Creek (continued)
Location Date
Alkalinity
(mg
CaCO3/L)
E. Coli.
(mpn/100
ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
LCR3.7 7/10/2013 101 0.57 85.5 10.9
LCR9.9 7/10/2013 95.9 6.11
LCR14 7/10/2013 1986 0.59 32.8 2.06
LCR17.2 7/10/2013 12.3 0.28
LCR18.6 7/10/2013 11 0.25
LCR19.5 7/10/2013 0.5 NA 0.58
LCR27.8 7/10/2013 0.13 8.14 0.38
LCT3D.5 7/10/2013 20 0.72 252 4.75
HK-0.8 7/10/2013 0.3 16.4 0.64
HLB-0.8 7/10/2013 0.12 10 0.52
HGB-1.7 7/10/2013 0.22 12.5 0.5
HLW-2.5 7/10/2013 0.18 12.6 1.2LCR26.5 7/10/2013 0.13 8.01 < 0.2
PRG-0.3 7/10/2013 0.53 61.9 1.03
LCR3.7 8/7/2013 54 0.42 27.7 8.55
LCR9.9 8/7/2013 35 8.41
LCR14 8/7/2013 365 0.79 15.8 1.12
LCR17.2 8/7/2013 7.7 0.21
LCR18.6 8/7/2013 7.55 < 0.2
LCR19.5 8/7/2013 0.99 10.5 < 0.2
LCR27.8 8/7/2013 0.27 6.81 < 0.2
LCT3D.5 8/7/2013 101 0.58 74.5 1.89
HK-0.8 8/7/2013 0.97 5.91 < 0.2
HLB-0.8 8/7/2013 0.22 9.66 0.27
HGB-1.7 8/7/2013 0.26 14 0.71
HLW-2.5 8/7/2013 0.31 8.27 0.82
LCR26.5 8/7/2013 0.2 7.35 0.46
PRG-0.3 8/7/2013 0.78 72.6 4.83
LCR3.7 9/4/2013 113 365 0.57 34.5 8.61
LCR9.9 9/4/2013 42.5 4.84
LCR14 9/4/2013 85 687 0.68 25.9 5.15
LCR17.2 9/4/2013 10.8 0.56
LCR18.6 9/4/2013 9.83 0.29
LCR19.5 9/4/2013 80 0.88 8.63 0.39
LCR27.8 9/4/2013 33 0.26 8.24 0.44
LCT3D.5 9/4/2013 132 115 0.54 82.9 3.81
HK-0.8 9/4/2013 40 0.68 7.38 0.52
HLB-0.8 9/4/2013 23 0.2 9.34 0.37
HGB-1.7 9/4/2013 45.5 0.41 17.3 0.47
HLW-2.5 9/4/2013 67 0.28 8.01 1.33
LCR26.5 9/4/2013 32 0.21 8.32 0.46
PRG-0.3 9/4/2013 233 0.71 61.2 3.02
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Little Otter Creek
Location DateE. Coli
(mpn/100ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
LOC4.3 4/3/2013 32.7 18.3 6.8 7.98
MDC1.2 4/3/2013 36.6 27.9 1.5 3.59
LOC4.3 5/1/2013 49.8 24.4 8.74 11.5
MDC1.2 5/1/2013 48 36.9 2.68 58.2
LOC4.3 6/5/2013 147 165 86.1 42 55.4
MDC1.2 6/5/2013 63 164 150 3.81 5.87
LOC4.3 7/10/2013 152 296 158 40.8 42.2
MDC1.2 7/10/2013 119 769 528 15.7 15.7
LOC4.3 8/7/2013 18 71.8 49.9 10 12.4
MDC1.2 8/7/2013 108 183 153 5.46 6.43
LOC4.3 9/4/2013 108 116 59.7 29.6 48.6
MDC1.2 9/4/2013 184 166 140 4.8 6.15
Shaded cells represent values that exceed the relevant VT Water Quality Standard:E.coli = 77 MPN/100 mL; Turbidity (cold water Class B) = 10 NTUs
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Middlebury River
Location Date E. Coli.(mpn/100ml)
TN(mg-N/l)
TP(ug P/L)
TDP(ug P/L)
TSS(mg/L)
Turbidity(NTU)
MIR1.5 4/3/2013 16.7 3.53
MIR5.7 4/3/2013 6.97 1.41
MIR1.5 5/1/2013 13.2 2.91
MIR5.7 5/1/2013 6.8 0.21
MIR1.5 6/5/2013 84 22.5 4.39
MIR5.7 6/5/2013 11 8.37 0.25
MIR1.5 7/10/2013 345 50.1 7.83
MIR5.7 7/10/2013 64 14.4 0.69
MIR1.5 8/7/2013 76 21.3 3.26
MIR5.7 8/7/2013 9 7.47 0.25
MIR1.5 9/4/2013 101 30.5 3.41
MIR5.7 9/4/2013 28 10.3 0.35
Shaded cells represent values that exceed the relevant VT Water Quality Standard:
E.coli = 77 MPN/100 mL; Turbidity (cold water Class B) = 10 NTUs
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New Haven River
Location DateE. Coli.
(mpn/100ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
NHR2 4/3/2013 25.7 6.62
NHR9 4/3/2013 7.06 0.86
NHR2 5/1/2013 5.45 0.57
NHR9 5/1/2013 9.41 1.05
NHR2 6/5/2013 59 13.2 1.54
NHR9 6/5/2013 29 7.77 0.52
NHR11.5 6/5/2013 6
NHR2 7/10/2013 88 23.4 2.35
NHR9 7/10/2013 32 10.3 0.57
NHR11.5 7/10/2013 33
NHR2 8/7/2013 276 15.8 2.24
NHR9 8/7/2013 17 6.98 0.34
NHR11.5 8/7/2013 30
NHR2 9/4/2013 166 26.2 0.87NHR9 9/4/2013 44 7.5 NS
NHR11.5 9/4/2013 28
Shaded cells represent values that exceed the relevant VT Water Quality Standard:
E.coli = 77 MPN/100 mL; Turbidity (cold water Class B) = 10 NTUs
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Otter Creek (Lower)
Location DateE. Coli.
(mpn/100ml)
TN
(mg-N/l)
TP
(ug P/L)
TDP
(ug P/L)
TSS
(mg/L)
Turbidity
(NTU)
OTR18 4/3/2013 0.52 17.9 4.73
OTR7.3 4/3/2013 0.5 22 5.11
OTR18 5/1/2013 0.36 24.8 1.53
OTR7.3 5/1/2013 0.36 30.9 3.77
OTR18 6/5/2013 84 0.5 47.5 7.66
OTR7.3 6/5/2013 89 0.52 47 8.58
OTR18 7/10/2013 102 0.46 96.1 4.54OTR7.3 7/10/2013 75 0.55 133 16.7
OTR18 8/7/2013 16 0.51 25.6 2.37
OTR7.3 8/7/2013 50 0.6 33.5 6.11
OTR18 9/4/2013 135 0.48 29.4 4.33
OTR7.3 9/4/2013 125 0.61 35.7 7.65
Shaded cells represent values that exceed the relevant VT Water Quality Standard:
E.coli = 77 MPN/100 mL; Turbidity (warm water Class B) = 25 NTUs.
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Attachments
1 Lemon Fair River2013 Water Quality Summary2 Lewis Creek2013 Water Quality Summary3 Little Otter Creek2013 Water Quality Summary4 Middlebury River2013 Water Quality Summary5 New Haven River2013 Water Quality Summary6 Otter Creek (Lower)2013 Water Quality Summary
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Site Location Town
LFR0 Weybridge Road bridge Weybridge
LFR1.2 Prunier Road bridge Weybridge
LFR6.7 Route 125 bridge. Cornwall
LFR12 Downstream of Route 74 bridge Shoreham
LFR15.8 Shacksboro Road bridge Shoreham
LFR23.9 Murray Road Bridge Orwell
LFB2.5 Sperry Road crossing, Beaver Branch Cornwall
LFBS1-0.9 Route 125 crossing, trib to Beaver Branch Cornwall
Lemon Fair River - 2013 Water Quality SummaryAddison County Riverwatch Collaborative
The Addison County Riverwatch Collaborative
has been monitoring water quality in the Lemon
Fair River since 2003. For the 2012 and 2013
seasons, the Lemon Fair River has been thesubject of a more intensive monitoring focus,
where rotational as well as sentinel stations
were monitored and additional parameters
were tested. Six sites are located on the main
stem, and two stations are located on the
Beaver Branch tributary in the lower watershed
(see table at right).
During 2013, sampling occurred on two spring dates (April 3 and May 1) and four summer dates (June 5,
July 10, August 7, and September 4). The spring and early summer dates represented moderate flow
conditions on the river, based on streamflow gages in area rivers. August and September sample datescaptured baseflow conditions, while the July 10 event captured moderate to high flows following a
storm event on July 3-4 and higher-than-normal May and June rainfall. On an average annual basis,
flows in 2013 were near normal in the Addison County watersheds monitored by the Collaborative.
Samples from the Lemon Fair watershed weretested for phosphorus (total and dissolved), total
nitrogen, total suspended solids, and turbidity; E.coli was tested only on the summer dates. As detailed
in the following sections, results suggest the need to focus on improved land management practices in
the middle stretch of this river between stations LFR15.8 and LFR6.7 (Bridport, Shoreham).
E.colicounts at most sites in the Lemon Fair watershed often exceeded the state standard of 77
organisms/ 100 mL on the four summer sampling dates. Detected E.coli counts were relatively
consistent with historic monitoring results. Figure 1 shows results for the stations located on the LemonFair main stem from upstream (right) to downstream (left). During the low-flow conditions on August
and September sample dates, a possible local contribution of E.coli is evidenced by the jump in readings
between stations LFR12 and LFR6.7. This pattern was also evident during low-flow sampling events
from 2012.
1
10
100
1000
10000
E.coli(MPN
per100mL)
6/5/2013
7/10/2013
8/7/2013
9/4/2013
SamplingDates
VT WQ Standard = 77 MPN / 100 mL
LFR0 LFR1.2 LFR6.7 LFR15.8LFR12 LFR23.9
Figure 1. 2013 E. Coli results for stations along the Lemon Fair River main stem.
20122013
Focus Watershed
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The drop in E.coli counts between station LFR6.7 and LFR1.2 may reflect decay of E.coli concentrations
with downstream distance or dilutionary effects of groundwater and/or tributary inputs. Beaver Brook
enters the Lemon Fair River between these two stations. Two stations are monitored on this tributary; in
2013, E coli counts ranged from 214 to 649 MPNs/100 mL in the downstream station (LFB2.5) and from
61 to 1,553 MPNs/100 mL at the upstream station (LFBS1.09).
E.coli results from both 2012 (a drier-than-normal year) and 2013 (a near normal year) are summarized
in Figure 2 (total number of samples at each station = 8). E.coli counts at stations LFR15.8, LFR12, and
LFR6.7 along the main stem in Bridport and Shoreham are chronically above the state water quality
standard of 77 MPN/100mL, consistent with historic sampling results.
Figure 2. 2012 and 2013 E. Coli results for focus stations in the Lemon Fair watershed.
Turbiditylevels at the sampled stations in Lemon Fair watershed ranged from 2.5 to 136 NTUs in 2013.
Concentrations exceeded the Vermont state standard of 25 NTUs (for Class B warm-water fisheries) at a
majority of stations on nearly all sample dates except the upstream station LFR23.9 (Murray Road
crossing) and the two stations on Beaver Brook. Figure 3 shows results for the stations located on the
Lemon Fair main stem from upstream (right) to downstream (left). An increase in Turbidity is evident
between LFR15.8 and LFR12 on all of the six sample dates, consistent with historic results. The decline
in Turbidity levels at station LFR1.2 and LFR0 on a few sample dates (e.g., July 10, September 4) mayreflect dilutionary effects of groundwater recharge zones or tributary inputs.
Turbidity results from both 2012 (a drier-than-normal year) and 2013 (a near normal year) are
summarized in Figure 4 (total number of samples at each station = 12). Turbidity levels at stations
LFR12, LFR6.7, and LFR1.2 along the main stem in Shoreham, Cornwall, and Weybridge are chronically
above the state water quality standard of 25 NTUs, consistent with historic sampling results.
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Figure 3. 2013 Turbidity results for stations along the Lemon Fair River main stem.
Figure 4. 2012 and 2013 Turbidity results for focus stations in the Lemon Fair watershed.
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Total Suspended Sedimentsranged from 1.1 to 128 mg/L in 2013 at the eight focus stations. TSS can be
related to Turbidity by a linear regression of log-transformed data (Figure 5).
Figure 5. Realtionship of TSS to Turbidity for 2012 and 2013 results
at eight focus stations in the Lemon Fair watershed.
Phosphoruswas detected at moderate levels during the six spring and summer sampling dates of 2013.
Concentrations ranged from 14.5 to 460 ug/L, with an average of 120 ug/L. With the exception ofupstream station LFR23.9 (Murray Road Bridge), the mean of the two available, low-flow, summer
sample results at each station (including the two Beaver Branch sites) exceeded the recently proposed
instream phosphorus criterion of 44 ug/L for warm-water medium gradient (WWMG) wadeable stream
ecotype in Class B waters. It is possible that Lemon Fair River would instead be classified as a slow-
winder stream ecotype (not yet determined for the reaches sampled); there is no proposed instream
phosphorus criterion to date for the slow-winder ecotype.
Figure 6 shows results for the stations located on the Lemon Fair main stem from upstream (right) to
downstream (left). An increasing trend in phosphorus with downstream distance is suggested by the
results. Of particular note is the increase in phosphorus concentration between stations LFR23.9 and
LFR12consistent with the previously indicated rise in turbidity for the same stations. Dissolved
phosphorus results for these dates (not shown) indicate that this rise is predominantly associated withthe particulate fraction of total phosphorus.
Total Phosphorus results from both 2012 (a drier-than-normal year) and 2013 (a near normal year) are
summarized in Figure 7 (total number of samples at each station = 12). Phosphorus levels at stations
LFR12, LFR6.7, and LFR1.2 along the main stem in Shoreham, Cornwall, and Weybridge are particularly
elevated, consistent with the pattern for turbidity.
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Figure 6. 2013 Total Phosphorus results for stations along the Lemon Fair River main stem.
Figure 7. 2012 and 2013 Total Phosphorus results for focus stations in the Lemon Fair watershed.
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Nitrogenconcentrations were generally low (ranging from 0.2 to 1.2 mg/L) and well below the state
standard for nitrogen as nitrate (5 mg/L). The mean of the four, low-flow, summer sample results at
sites LFR6.7, LFR1.2, LFR0 and Beaver Brook station LFBS1-0.9 exceeded the recently proposed instream
nitrogen criteria of 0.75 mg/L for WWMG wadeable stream ecotype in Class B waters.
Focus Study Findings:
For the 2012 and 2013 seasons, the Lemon Fair River was the subject of a more intensive monitoringfocus, including additional sampling stations and testing parameters.
At stations LFR15.8, LFR12, and LFR6.7 along the main stem in Bridport and Shoreham and at theupper Beaver Brook station LFBS1.09, E.coli counts are chronically above the state water quality
standard of 77 MPN/100mL, and often above the federal health-based standard of235 MPN/100 mL, consistent with historic sampling results.
At stations LFR12, LFR6.7, and LFR1.2 along the main stem in Shoreham, Cornwall, and Weybridge:o turbidity levels are chronically above the state water quality standard of 25 NTUs; ando phosphorus levels are particularly elevated, consistent with the pattern for turbidity.
Sampling results suggest the need to focus on improved land management practices in the middlestretch of the Lemon Fair River between stations LFR15.8 and LFR6.7 (Bridport, Shoreham).
2014: In years 2014 through 2017, the Lemon Fair watershed will rotate back to a reduced frequency of
monitoring at two sentinel stations, LFR6.7 and LFR12. The Addison County Riverwatch Collaborativewill sample for total and dissolved phosphorus, total nitrogen, total dissolved solids, turbidity, and E.coli.
For more information, contact the Lemon Fair interim sampling coordinator:
Barb Otsuka, 388-6829,[email protected] County Riverwatch Collaborative coordinator: Matt Witten, 434-3236, [email protected]
or visit our web page at: www.acrpc.org/acrwc
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Site Location Town
LCR3.7 Old Route 7 Bridge Ferrisburgh
LCR9.9 Upper Covered Bridge, Roscoe Rd. Charlotte
LCR14 Tyler Bridge Monkton
LCR17.2 Starksboro Ballfields Starksboro
LCR18.6 Lewis Creek Farm footbridge Starksboro
LCR19.5 Parsonage Road bridge Starksboro
LCR27.8 Hillsboro Road Starksboro
LCT3D.5 Silver Street culvert Monkton
Lewis Creek - 2013 Water Quality SummaryAddison County Riverwatch Collaborative
The Addison County Riverwatch Collaborative has
been monitoring water quality in the Lewis Creek since
1992. For the 2012 and 2013 seasons, Lewis Creekwas the subject of a more intensive monitoring focus,
where rotational as well as sentinel stations were
monitored and additional parameters were tested.
Two sentinel sites (LCR3.7 and LCR14) and six
rotational sites located on the main stem and Pond
Brook tributary were sampled (see table at right).
In 2013, six new stations were established in the headwaters of the Lewis Creek watershed to evaluate
baseline water quality conditions in the upper main stem and the Hillsboro Brook, High Knob Brook,
Hogback Brook, Hollow Brook and Pringle Brook tributaries in support of biomonitoring studies to be
carried out by the VT Agency of Natural Resources (VTANR). Results of this special study will be
separately reported by VTANR.
During 2013, sampling occurred on two spring dates (April 3 and May 1) and four summer dates (June 5,
July 10, August 7, and September 4). The spring and early summer dates represented moderate flow
conditions on the river, based on records from the USGS streamflow gage located at the Route 7
crossing. August and September sample dates captured baseflow conditions, while the July 10 event
captured moderate to high flows following a storm event on July 3-4 and higher-than-normal May and
June rainfall. On an average annual basis, flows in 2013 were near normal in the Addison County
watersheds monitored by the Collaborative. Samples from the Lewis Creek watershed weretested for
E.coli, total phosphorus, total nitrogen, and turbidity; E.coli and Total Nitrogen were tested only on the
summer dates. As part of the special study of biocriteria, alkalinity was tested at select sites during the
September event only.
E.colicounts in the Lewis Creek at three select sites exceeded the state standard of 77 organisms/100
mL on a majority of the sample dates. E.coli results exceeded the federal health standard of 235
MPN/100 mL at LCR3.7 during the September event, and at LCR14 on three out of the four summer
sampling events. Detected E.coli counts at these sites in the 2013 season were largely consistent with
historic results.
20122013
Focus Watershed
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Turbiditylevels in the Lewis Creek at the sampled stations ranged from
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Nitrogenlevels were detected at very low concentrations during the six spring and summer sampling
dates, well below the state standard for nitrogen as nitrate (5 mg/L). Concentrations ranged from 0.13
to 0.99 mg/L, with an average of 0.5 mg/L. The mean value of the two available low-flow summer
sample results at site LCR19.5 was above the recently proposed instream nitrogen criteria of 0.75 mg/L
for WWMG wadeable stream ecotype in Class B waters.
2014: In years 2014 through 2017, the Lewis Creek watershed will rotate back to a reduced frequency
of monitoring at two sentinel stations, LCR3.7 and LCR14. The Addison County Riverwatch Collaborative
will sample for total phosphorus, turbidity, and E.coli.
For more information, contact the Lewis Creek sampling coordinator:
Louis DuPont, 453-5538, [email protected]
Addison County Riverwatch Collaborative coordinator: Matt Witten, 434-3236, [email protected]
or visit our web page at: www.acrpc.org/acrwc
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Site Location Town
LOC4.3 Route 7 Bridge Ferrisburgh
MDC1.2 Wing Rd./Middlebrook Rd. (South) Ferrisburgh
Little Otter Creek - 2013 Water Quality SummaryAddison County Riverwatch Collaborative
The Addison County Riverwatch Collaborative has been monitoring water quality in the Little Otter
Creek since 1997. For years 2012 through 2015, the number of sampling locations in this watershed has
been reduced to two sentinel stations, LOC4.3 and MDC1.2. During 2013, sampling occurred on two
spring dates (April 3 and May 1) and four summer dates (June 5, July 10, August 7, and September 4).
The spring and early summer dates represented moderate flow conditions on the river, based on
records from the USGS streamflow gage located at the Route 7 crossing. August and September sample
dates captured baseflow conditions, while the July 10 event captured moderate to high flows following a
storm event on July 3-4 and higher-than-normal May and June rainfall. On an average annual basis,
flows in 2013 were near normal in the Addison County watersheds monitored by the Collaborative.Samples were tested for phosphorus (total and dissolved), total suspended solids, and turbidity; E.coli
was tested only on the summer dates.
E.colicounts at the Little Otter Creek watershed stations were above the state water-quality standard of
77 MPN/100 mL on three of the four summer sample dates, but below the federal health-based
standard of 235 MPN/100 mL. E.coli concentrations detected at these stations during 2013 are
relatively consistent with historic monitoring results. Mud Creek station (MDC1.2) has traditionally had
elevated E.coli as it is located directly downstream of a dairy pasture where livestock have direct access
to the stream. Low flow rates probably contributed to the elevated E.coli counts in the September 4
sample.
Turbiditylevels in the Little Otter Creek at the two sentinel stations were moderate and often exceeded
the Vermont standard of 10 NTUs (for Class B cold-water fisheries). Values ranged from 3.6 to 58 NTUs,
with a mean level of 22.8 NTUs for the six sample dates. Highest turbidity concentrations in 2013 at
these stations were detected during May or June events when streamflows were somewhat elevated as
a result of record rainfall amounts. Turbidity results for 2013 at these two stations were largely
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consistent with historic trends. Based on past years sampling results,turbidity can increase well above
the state standard at times of high flowduring a Summer thunderstorm, or during Spring runoff
conditions.
Phosphoruslevels were detected at low to moderate concentrations during the six spring and summer
sampling dates. Concentrations ranged from 32.7 to 769 ug/L, with an average of 175 ug/L. Maximum
concentrations for the season were detected during moderate flow conditions on July 10 following the
storm event on July 3-4 and higher-than-normal May and June rainfall. Total Phosphorus concentrations
detected in 2013 were generally consistent with historic data. Vermont recently proposed in-stream
phosphorus criteria for aquatic life and aesthetics uses in wadeable streams (VTDEC, 2009). The mean
concentration of Total Phosphorus for the two available, low-flow summer sample dates at each
sentinel stations exceeded the proposed criteria of 44 ug/L for the warm-water medium gradient
(WWMG) wadeable stream ecotype in Class B waters.
2014: The Addison County Riverwatch Collaborative will continue to monitor for E.coli, phosphorus
(total and dissolved), total suspended sediments, and turbidity at these two sentinel sites in 2014. An
increased number of parameters and additional monitoring sites will be evaluated when a more
intensive monitoring focus rotates back to the Little Otter Creek for a two-year period beginning in the
year 2016.For more information, contact the Little Otter Creek sampling coordinator:
Deb Healey, 475-2944, [email protected]
Addison County Riverwatch Collaborative coordinator: Matt Witten, 434-3236, [email protected]
or visit our web page at: www.acrpc.org/acrwc
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Site Location Town
MIR1.5 Shard Villa Rd. Bridge Middlebury
MIR5.7 Midd. Gorge @ Rte 125 Bridge Middlebury
Middlebury River - 2013 Water Quality SummaryAddison County Riverwatch Collaborative
The Addison County Riverwatch Collaborative has been monitoring water quality in the Middlebury
River since 1993. For years 2010 through 2013, the number of sampling locations in this watershed has
been reduced to two sentinel stations, MIR1.5 and MIR5.7. During 2013, sampling occurred on two
spring dates (April 3 and May 1) and four summer dates (June 5, July 10, August 7, and September 4).
The spring and early summer dates represented moderate flow conditions on the river, based on
records from area USGS streamflow gages. August and September sample dates captured baseflow
conditions, while the July 10 event captured moderate to high flows following a storm event on July 3-4
and higher-than-normal May and June rainfall. On an average annual basis, flows in 2013 were near
normal in the Addison County watersheds monitored by the Collaborative. Samples were tested for
phosphorus and turbidity; E.coli was tested only on the summer dates.
E.colicounts at the Middlebury Gorge, a popular swimming hole near the Route 125 bridge (MIR5.7),
were well below the federal health-based standard of 235 MPN/100 mL on all four summer sample
dates. Results were also below the state water-quality standard of 77 organisms/100 mL. E.coli counts
at the downstream station at Shard Villa Road bridge (MIR1.5) were at or above the state standard on all
four summer sampling dates, and the July sample exceeded the federal health-based standard. These
results are generally consistent with historic summer sampling results, which have shown an increase in
E.coli levels in the Middlebury River downstream of the Route 7 bridge.
Turbiditylevels in the Middlebury River were low and below the Vermont state standard of 10 NTUs (for
Class B cold-water fisheries). Values ranged from 0.2 to 7.8 NTUs, with an average level of 2.4 NTUs for
all six sample dates. Based on past years sampling results, Turbidity can increase well above the state
standard at times of high flowduring a summer thunderstorm, or during Spring runoff conditions
particularly in the lower section of the river below the Route 7 bridge.
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Phosphoruslevels were detected at relatively low concentrations during the six spring and summer
sampling dates. Concentrations ranged from 6.8 to 50.1 ug/L, with an average of 17.4 ug/L. Total
Phosphorus concentrations detected in 2013 were generally consistent with historic data. Vermont
recently proposed in-stream phosphorus criteria for aquatic life and aesthetics uses in wadeable
streams (VTDEC, 2009). The mean concentration of Total Phosphorus for the two available low-flow
summer sample dates at each site did not exceed the proposed criterion of 44 ug/L for the warm-water
medium gradient (WWMG) wadeable stream ecotype in Class B waters.
2014: An increased number of parameters and additional monitoring sites will be evaluated when a
more intensive monitoring focus rotates back to the Middlebury River for a two-year period beginning in
the year 2014. Additional stations will be added in the headwaters located in Ripton to capture baseline
water quality conditions in the South, Middle and North Branches of the Middlebury River. Some of
these stations will be co-located with VT Agency of Natural Resources bio-monitoring stations. A greater
density of sampling stations will be established downstream of the East Middlebury village to produce
an updated assessment of water quality conditions in this lower part of the watershed which is more
intensively developed and farmed.
For more information, contact the Middlebury River sampling coordinator:Heidi Willis, 352-4327, [email protected]
Addison County Riverwatch Collaborative coordinator: Matt Witten, 434-3236, [email protected]
or visit our web page at: www.acrpc.org/acrwc
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Site Location Town
NHR2 Muddy Branch confluence New Haven
NHR9 South St. Bridge Bristol
NHR11.5 Bartlett's Falls Pool Bristol
New Haven River - 2013 Water Quality SummaryAddison County Riverwatch Collaborative
The Addison County Riverwatch Collaborative has been monitoring water quality in the New Haven River
since 1993. For years, 2012 through 2015, the number of sampling locations in this watershed has been
reduced to two sentinel stations, NHR2 and NHR9, and a third recreational site monitored only for
pathogens (NHR11.5). During 2013, sampling occurred on two spring dates (April 3 and May 1) and four
summer dates (June 5, July 10, August 7, and September 4). The spring and early summer dates
represented moderate flow conditions on the river, based on records from the USGS gage on the New
Haven River at Brooksville. August and September sample dates captured baseflow conditions, while
the July 10 event captured moderate to high flows following a storm event on July 3-4 and higher-than-
normal May and June rainfall. On an average annual basis, flows in 2013 were near normal in the
Addison County watersheds monitored by the Collaborative. Samples were tested for phosphorus andturbidity; E.coli was tested only on the summer dates.
E.colicounts at popular recreational sites (South St. Bridge, NHR9; Bartletts Falls, NHR11.5) were below
the federal health-based standard of 235 MPN/100 mL and the state water-quality standard of 77
organisms/100 mL on all four summer dates. In the lower watershed, however, the station near Nash
Bridge in New Haven (NHR2) indicated E.coli counts elevated above the state standard in July, August
and September. The August result exceeded the federal health-based standard. Consistent with historic
results, an increasing trend in E.coli levels is evident with distance downstream from station NHR11.5 to
NHR2. Developed and agricultural land uses are more prevalent in the lower New Haven River
watershed.
Turbiditylevels on the New Haven River at the two sampled stations ranged from 0.3 to 6.6 NTUs, with
a mean level of 1.6 NTUs for the six sample dates. These turbidity levels were below the Vermont state
standard of 10 NTUs (for Class B cold-water fisheries). Results from 2012 are largely consistent with
historic trends. Based on past years sampling results, turbidity can increase well above the standard at
times of increased flowduring a summer thunderstorm, or during spring runoff conditionsespecially
in the lower reaches of the river below the Bristol Flats. A slight increasing trend in turbidity with
distance downstream is generally observed during all flow conditions.
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Phosphoruswas detected at relatively low concentrations on the New Haven River during the spring
and summer sampling dates. Concentrations ranged from 5.4 to 26 ug/L, with an average of 13 ug/L.
Results were consistent with historic trends, which indicate an increase in concentrations with distance
downstream. At all stations, moderately high concentrations of Total Phosphorus have been detected in
past years at times of high flow and runoff. In 2013, the mean concentration of Total Phosphorus for
the two available low-flow summer sample dates (August 7, September 4) at each of the New Haven
River sentinel sites did not exceed the proposed criterion of 44 ug/L for the warm-water medium
gradient (WWMG) wadeable stream ecotype in Class B waters.
2014:The Addison County Riverwatch Collaborative will continue to monitor for E.coli, phosphorus and
turbidity at these sentinel sites in 2014. An increased number of parameters and additional monitoring
sites will be evaluated when a more intensive monitoring focus rotates back to the New Haven River for
a two-year period beginning in the year 2016.For more information, contact the New Haven River sampling coordinator:
Pete Diminico, 453-3899, [email protected]
Addison County Riverwatch Collaborative coordinator: Matt Witten, 434-3236, [email protected] visit our web page at: www.acrpc.org/acrwc
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Otter Creek - 2013 Water Quality SummaryAddison County Riverwatch Collaborative
Site Location Town
OTR18 Twin Bridges Picnic Area Weybridge
OTR7.3 Vergennes Falls/below outfall Vergennes
The Addison County Riverwatch Collaborative has been monitoring water quality in the lower Otter
Creek since 1992. For years 2010 through 2013, the number of sampling locations in this watershed has
been reduced to two sentinel stations. The downstream-most sentinel station is OTR7.3 at the
Vergennes Falls below the outfall for the Vergennes wastewater treatment facility. In 2013, the upper
sentinel station at Belden Falls was replaced by station OTR18 at the Twin Bridges Picnic Area, due to
access limitations at the Belden Falls site.
During 2013, sampling occurred on two spring dates (April 3 and May 1) and four summer dates (June 5,
July 10, August 7, and September 4). The spring and early summer dates represented moderate flowconditions on the river, based on records from the USGS gage on the Otter Creek at Middlebury and
other area gages. August and September sample dates captured baseflow conditions, while the July 10
event captured moderate to high flows following a storm event on July 3-4 and higher-than-normal May
and June rainfall. On an average annual basis, flows in 2013 were near normal in the Addison County
watersheds monitored by the Collaborative. Samples were tested for phosphorus, nitrogen and
turbidity; E.coli was tested only on the summer dates.
E.coliconcentration in the Otter Creek was nearly at or above the state water-quality standard of 77
MPN/100 mL in each station for three out of the four summer sample dates. None of the reported E.coli
counts exceeded the federal health-based standard of 235 MPN/100 mL. E.coli concentrations detected
at these sentinel stations during 2013 are relatively consistent with historic results.
Turbiditylevels in the Otter Creek at the two sentinel stations were low and below the Vermont state
standard of 25 NTUs (for Class B warm-water fisheries). Values ranged from 1.5 to 16.7 NTUs, with a
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mean value of 6.1 NTUs for the six sample dates. Results are consistent with historic data, which
indicate that median turbidity values are generally less than 10 NTUs.
Phosphoruslevels were detected at relatively low concentrations during the six spring and summer
sampling dates. Concentrations ranged from 17.9 to 133 ug/L, with an average of 45 ug/L. Moderately
high concentrations of Total Phosphorus have been recorded in past years at times of high flow and
runoff. In 2013, the mean concentration of Total Phosphorus at each of the two available low-flow
summer sample dates (August 7 and September 4) was lower than the proposed criterion of 44 ug/L for
the warm-water medium gradient (WWMG) wadeable stream ecotype in Class B waters. The Otter
Creek might instead be classified as a Slow Winder stream, but criteria have not yet been developed for
this ecotype.
Nitrogenlevels were detected at very low concentrations during the six spring and summer sampling
dates, well below the state standard for nitrogen as nitrate (5 mg/L). Concentrations ranged from 0.36
to 0.61 mg/L, with an average of 0.5 mg/L. The mean values of the summer, low-flow, sample results at
sites OTR18 and OTR7.3 (0.50 and 0.61 mg/L, respectively) were below the recently proposed instream
nitrogen criteria of 0.75 mg/L for WWMG wadeable stream ecotype in Class B waters.
2014: An increased number of monitoring sites along the Otter Creek will be evaluated in 2014 when a
more intensive monitoring focus rotates back to the watershed for a two-year period.
For more information, the Otter Creek sampling coordinator:
Heidi Willis, 352-4327, [email protected]
Addison County Riverwatch Collaborative coordinator: Matt Witten, 434-3236, [email protected]
or visit our web page at: www.acrpc.org/acrwc