HomeMy WebLinkAboutDan R Fecal Addendum TMDLNorth Carolina Addendum
Total Maximum Daily Load (TMDL) for Impaired Segments
in the Dan River Watershed to Virginia TMDLs Approved by
EPA Region 3
Assessment units (AU) for the Dan River, 22-(31.5)a, 22-(31.5)b, 22-(38.5), 22-(39)a,
22-(39)b and for the Smith River, 22-40-(1), 22-40-(2.5), 22-40-(3)
Final Report July 2009
EPA Approved July 31, 2009
Roanoke River Basin
Submitted by:
NC Department of Environment and Natural Resources
Division of Water Quality
1617 Mail Service Center
Raleigh NC 27699-1617
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Introduction
The Virginia Department of Environmental Quality (DEQ) developed bacteria Total
Daily Maximum Loads (TMDL) for Dan River, Blackberry Creek, Byrds Branch, Double
Creek, Fall Creek, Leatherwood Creek, Marrowbone Creek, North Fork Mayo River,
South Fork Mayo River, Smith River, Sandy Creek, and Sandy River watersheds. EPA
Region 3 approved the TMDLs on December 8, 2008
(http://www.deq.virginia.gov/tmdl/apptmdls/roankrvr/danec.pdf). The Dan River
watershed encompasses a large drainage area within North Carolina and Virginia. This
addendum to the TMDLs will further address North Carolina impaired waters that are
contained in the same hydrologic units as the Virginia TMDLs. The impaired waters in
NC are:
Dan River - AU#s 22-(31.5)a, 22-(31.5)b, 22-(38.5), 22-(39)a, 22-(39)b and
Smith River - AU#s 22-40-(1), 22-40-(2.5), 22-40-(3)
In order to approve these TMDLs for the NC portions of the watershed, EPA Region 4
requested the following supplemental information.
Watershed Description
This TMDL addendum covers the Dan River watershed that is located partially or wholly
within the North Carolina counties of Surry, Stokes, Rockingham, Caswell, Forsyth and
Guilford. This watershed is located in the USGS Cataloging Units 03010103 and
03010104. For purposes of this TMDL addendum this excludes the Hyco Creek
watershed since it flows into the Dan River downstream of the impairment. (The VA
TMDL also excluded this watershed).
Impairment Description
The Dan and Smith Rivers are on the North Carolina draft 2008 303(d) list of impaired
waters for fecal coliform bacteria. The NC water quality standard for fecal coliform
bacteria is discussed in section ‘Water Quality Target’ (below). A rolling series of 5
fecal bacteria samples were taken over multiple 30 day periods in 2004. A total of four
sampling stations represent the eight impaired AUs. A map is provided in Figure 1
depicting locations of sampling stations and impaired AUs. Sampling stations and data
analysis are provided in Table 1.
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Table 1. Statistical Evaluation of 5 in 30 Sampling Data
Sampling Stations
N2300000 N2450000 N3000000 N3500000
Sampling Dates Geometric
Mean % > 400 Geometric
Mean % > 400 Geometric
Mean % > 400 Geometric
Mean % > 400
4/13/2004 - 5/4/2004 397.62 20% 299.19 20% 216.03 20% 271.51 40%
4/20/2004 - 5/5/2004 185.54 0% 141.53 0% 118.06 0% 161.01 20%
4/22/2004 - 5/18/2004 447.39 20% 192.86 20% 232.86 20% 224.82 40%
4/27/2004 - 5/25/2004 508.84 40% 316.06 40% 288.30 20% 256.36 40%
5/4/2004 - 5/27/2004 488.14 40% 433.69 60% 474.73 40% 439.06 60%
5/5/2004 - 6/3/2004 380.53 40% 316.33 60% 495.44 40% 320.67 40%
5/18/2004 - 6/8/2004 439.48 40% 637.85 80% 578.98 40% 349.83 40%
Water Quality Standard Violations for fecal coliform bacteria are bolded and italicized.
Figure 1. Sampling Station Locations and Impaired AUs
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Water Quality Target
The North Carolina fresh surface water quality standard in Class C waters states:
Organisms of the coliform group: fecal coliforms shall not exceed a geometric mean of
200/100 ml (membrane filter count) based upon at least five consecutive samples
examined during any 30 day period, nor exceed 400/100 ml in more than 20 percent of
the samples examined during such period; violations of the fecal coliform standard are
expected during rainfall events and, in some cases, this violation is expected to be caused
by uncontrollable nonpoint source pollution; all coliform concentrations are to be
analyzed using the membrane filter technique unless high turbidity or other adverse
conditions necessitate the tube dilution method; in case of controversy over results, the
MPN 5-tube dilution technique will be used as the reference method. (15A NCAC
02B.0211)
Wasteload Allocation (WLA) and Load Allocation (LA)
Table 2 shows the permitted NPDES facilities with their allocated loadings. These
facilities were assumed to be discharging at their permitted limits. With these limits, they
are not contributing to the fecal coliform impairment. In this case, the WLA equates to
the facility’s permit limit.
There are currently no permitted MS4s in this TMDL watershed.
Table 2. Wasteload allocations (WLAs) for each NPDES permitted facility
NPDES
Permit
Number
Facility Name AU# Concentration
(counts/100ml)
Permitted
Flow
(MGD)
Load
(counts/day)
NC0002828 Reidsville plant 22-(39)b 200 0.005 3.79E+07
NC0003441 Carolina Plant
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.015
*
NC0003468 Dan River Steam Station
22-(39)a,
22-(39)b 200 No Limit *
NC0021873 Mayodan WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 2.5
1.89E+10
NC0025071 Mebane Bridge WWTP
22-(39)a,
22-(39)b 200 13.5 1.02E+11
NC0025151 Dry Creek WWTP
22-(39)a,
22-(39)b 200 0.5 3.79E+09
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NC0025526 Walnut Cove WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.5
3.79E+09
NC0028746 Briarwood Subdivision WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.05
3.79E+08
NC0030180 Blanch Youth Center WWTP 22-(39)b 200 0.018 1.36E+08
NC0035173 Kobewieland Copper Products
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.025
1.89E+08
NC0037001 Bethany Elementary School
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.01
7.57E+07
NC0037311 Creekside Manor Assisted Living
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.01
7.57E+07
NC0040011 Yanceyville WWTP 22-(39)b 200 0.45 3.41E+09
NC0044750 Britthaven of Madison WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.025
1.89E+08
NC0044954 South Stokes High School
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.0173
1.31E+08
NC0044962 North Stokes High School
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.0115
8.71E+07
NC0056791 Horizons Residential Care Center
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.015
1.14E+08
NC0057720 Hidden Lakes Village, LLC
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.04
3.03E+08
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NC0059251 Quail Acres Mobile Home Park
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.018
1.36E+08
NC0060461 Abington WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.2
1.51E+09
NC0060542 Gold Hill Mobile Home Park
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.0176
1.33E+08
NC0060623 Stone Highway Mobile Home Park
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.015
1.14E+08
NC0067091 Mikkola Downs Subdivision WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.072
5.45E+08
NC0075027 Cains Way Mobile Home Park
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.0432
3.27E+08
NC0077135 Hidden Valley WWTP 22-(39)b 200 0.022 1.67E+08
NC0078115 Greystone Subdivision WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.032
2.42E+08
NC0078271 Betsy Jeff Penn 4H Education
22-(39)a,
22-(39)b 200 0.0084 6.36E+07
NC0079049 R.H. Johnson Construction WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.06
4.54E+08
NC0082384 Danbury WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.1
7.57E+08
NC0083933 Salem Quarters WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.06
4.54E+08
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NC0085189 Jose's Restaurant WWTP
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.005
3.79E+07
NC0087645 Milton WWTP 22-(39)b 200 0.025 1.89E+08
NC0087980 Pine Hall Elementary School WWTP
22-(31.5)a,
22-(31.5)b,
22-(38.5),
22-(39)a,
22-(39)b 200 0.004
3.03E+07
* These facilities have small sanitary components with negligible fecal coliform bacteria loading.
The Load Allocation (LA) was derived from the VA TMDL
(http://www.deq.virginia.gov/tmdl/apptmdls/roankrvr/danec.pdf). The TMDL is
presented in Table 3.
Table 3. Fecal Coliform Bacteria TMDL
WLA
(NC Point Sources)
LA
(NC + VA Nonpoint Sources)
MOS
(Margin of Safety) TMDL
1.39E+11 2.74E+12 Implicit 2.88E+12
Public Participation
Virginia DEQ held two public meetings for the draft Total Daily Maximum Loads
(TMDL) for Dan River, Blackberry Creek, Byrds Branch, Double Creek, Fall Creek,
Leatherwood Creek, Marrowbone Creek, North Fork Mayo River, South Fork Mayo
River, Smith River, Sandy Creek, and Sandy River Watersheds. A total of twenty-seven
people attended, including North Carolina residents. The Dan River Basin Association
(DRBA) is a bi-state organization with active members residing in North Carolina and
Virginia. DRBA members attended both meetings. DEQ did not receive any comments
during the public comment period. Public attendance sheets from these meetings are
provided.