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Home My WebLink AboutNCS000527_OTHER_20050808STORMWATER DIVISION CODING SHEET PERMIT NO. NCS DOC TYPE ❑FINAL PERMIT ❑ MONITORING INFO ❑ APPLICATION ❑ COMPLIANCE OTHER DOC DATE ❑ YYYYMMDD B. Everett Jordan Reservoir Phase I Nutrient TMDL — Final The equivalent treatment concentration method was used to determine allocations. This method satisfies NC General Statute 143-215.8B(b)(1) which requires equitable allocations. Thus, all wastewater treatment plants received allocations based on equitable levels of technology. Allocated annual generated loads were calculated by multiplying the maximum permitted flow by the equivalent treatment concentration and a conversion factor (3,044). These loads will be used in NPDES permits as annual loading targets. Compliance will be judged using the annual loads, not the equivalent treatment concentration. Allocated annual delivered loads calculated by multiplying allocated generated loads by the appropriate transport factor in Table 6. The sum of the allocated annual delivered loads must equal the WLA in Table 13. Summaries of the wasteload allocation analyses for the Upper New Hope Arm and Haw River Arm are listed below. Upper New Hope Arm. All of the available loading was allocated to the existing facilities. Therefore, there will be no new nitrogen or phosphorus bearing loads permitted in this watershed. There are four facilities discharging greater than 100,000 gallons per day in the watershed of the Upper New Hope Arm: The City of Durham- South Durham WRF, the Orange Water & Sewer Authority- Mason Farm WWTP, the Durham County- Triangle WWTP, and the Whippoorwill LLC- Carolina Meadows WWTP. These facilities account for 99.7% of the total permitted flow from point sources. The discharge allocations for these four facilities provide equivalent concentrations for each facility. For nitrogen, this equivalent concentration is 3.04 mg/L, and for phosphorus this equivalent is 0.23 mg/L. The remaining facilities in the Upper New Hope watershed were allocated at equivalent concentrations of 12.0 mg/L and 2.0 mg/L for nitrogen and phosphorus, respectively. Haw River Arm. All of the available loading was allocated to the existing facilities. Therefore, there will be no new nitrogen or phosphorus bearing loads permitted in this watershed. There are ten facilities discharging greater than 100,000 gallons per day in watershed of the Haw River Arm: The City of Greensboro- T.Z. Osborne WWTP, the City of Greensboro- North Buffalo Creek WWTP, the City of Burlington- Eastside WWTP, the City of Burlington- Southside WWTP, the City of Reidsville- Reidsville WWTP, the City of Graham- Graham WWTP, the City of Mebane - Mebane WWTP, the Town of Pittsboro- Pittsboro WWTP, the Quarterstone Farm Homeowners Association- Quarterstone Farm WWTP, and the Glen Raven Inc- Altamahaw Division plant. These facilities account for 99.3% of the total permitted flow from point sources. The discharge allocations for these ten facilities provide equivalent treatment levels for each facility. For nitrogen, this equivalent treatment level is 5.3 mg/L, and for phosphorus this equivalent is 0.67 mg/L. The remaining facilities in the Upper New Hope watershed were allocated at equivalent concentrations of 12.0 mg/L and 2.0 mg/L for nitrogen and phosphorus, respectively. 7.1.1 Permitting Options The strategy for point sources (i.e., wastewater dischargers) calls for all affected dischargers to implement appropriate nutrient controls. Each facility will receive annual mass discharge limits for total nitrogen and for total phosphorus in its NPDES permit. Limits will be expressed as end -of - pipe limits, that is, limits that will apply at the point of discharge. In order to meet the new.limits, it will be necessary for most dischargers to upgrade their facilities to effectively remove nutrients. The strategy also calls for all dischargers to optimize nutrient removal in their existing facilities while modifications are designed and built. DWQ Modeling & TMDL Unit 51 Chapter 5 Cape Fear River Subbasin 03-06-05 Including: New Hope Creek, Northeast Creek and Jordan Reservoir 5.1 Subbasin Overview Subbasin 03-06-05 at a Glance Land and Water Area Total area: 269 miz Land area; 251 miz Water area: 18 miz Population Statistics 2000 Est. Pop.: 112,558 people Pop. Density: 419 persons/miz I Land Cover (percent) Forest/ Wetland: 78.2% Surface Water: 8.2% Urban: 6.4% Cultivated Crop: 0.6% Pasture/ Managed (: Herbaceous: 6.6% Counties t Chatham, Durham, Orange and Wake Municipalities Apex, Cary, Durham and Morrisville Subbasin 03-06-05 overlies the geology of the Triassic basin, with all but the largest streams having regular very low flow periods. Most of the watershed is forested, with large urban areas in the eastern upland areas. Jordan Reservoir is a substantial percentage of the subbasin area. Development is occurring in the Wake County portion of the subbasin. Population is expected to grow by 250,000 people in counties with portions or all of their areas in this subbasin by 2020. Most of the growth is expected in Wake County, with only a small portion in this subbasin. There are 11 individual NPDES wastewater discharge permits in this subbasin with a permitted flow of 32.4 MGD (Figure 8). The largest are Triangle WWTP (12 MGD) and South Durham WRF (20 MGD). Refer to Appendix VI and Chapter 30 for more information on NPDES permit holders. Issues related to compliance with NPDES permit conditions are discussed below in Section 5.3 for Impaired waters and in Section 5.4 for other waters. Apex, Cary, Durham and Morrisville are required to develop Phase II stormwater programs (Chapter 31). There were four benthic macroinvertebrate community samples and one fish community sample (Figure 8 and Table 8) collected during this assessment period. Data were also collected from six ambient monitoring stations including one DWQ station, four UCFRBA (Appendix V) stations and one shared ambient station. Three reservoirs were also monitored. Refer to the 2003 Cape Fear River Basinwide Assessment Report at http:i/www.esb.etir.state.nc.us/bar.htmi and Appendix IV for more information on monitoring. Waters in the following sections are identified by assessment unit number (AU#). This number is used to track defined segments in the water quality assessment database, 303(d) Impaired waters list and the various tables in this basin plan; The assessment unit number is a subset of the DWQ index number (classification identification number). A letter attached to the end of the . AU# indicates that the assessment is smaller than the DWQ index segment. No letter indicates that the assessment unit and the DWQ index segment are the same. Chapter 5 — Cape Fear River Subbasin 03-06-05 50 a, NC Division of Water Quality Basinwide Planning Program August 8, 2005 ORANGE Figure 8 Cape Fear River Subbas111 in 03-06-05 H i� BB324 x � DURHAM A ti. 4 Chapel Hill BF57 Durham BA178 r J U f 1 1 SA197 _ 1 "38 BA209 A Gin � BA210 CHATHAM � 1 _ Jordan Lake _ 5 0 5 Apex Morrisville WAKE 10 Miles r Legend O subbe y A-0Ma MorW"N S=w Bft&w SUN- V Fish Cartxrnnily Matim NPOES Olscimgee A A Maier Mrc Use support Rang NNot s9 Ratd +'1 % No ❑aka Pnrt�y R°ads i CowAry aaundby tr Table 8 CAPE FEAR Subbasin 03-06-05 AU Number Classification Length/Area Aquatic Life Assessment Recreation Assessment Year/ Description AL Rating Station Result Parameter % Exc REC Rating Station Result Stressors Sources n _ - m- 16-41-1-17-2-(0.7) WS-IV NS 4.2 FW Miles NR ND From a point 1.3 miles upstream of NC Hwy 55 to BB 150 NR '2003 Northeast Creek - 16-41-1-(0.5)a C NSW 17.5 FW Miles S ND From source to Sandy Creek BB324 GF '2003 i641-1-(0.5)b C NSW 0.7 FW Miles S ND Habitat Degradation MS4 NPDES From Sandy Creek to a point 0.3 mile upstream of BF57 GF '2003 Durham County SR 2220 1641-1-(1 1.5)a WS-IV NS 0A FW Miles S ND Habitat Degradation MS4 NPDES From a point 0.3 mile upstream of Durham County SR BF57 GF 2003 2220 to SR 2220 1641-1-(11.5)b WS-IV NS 3.5 FW Miles I BA177 CE Low DO 12S NR- BA177 NCE Fecal Coliform Bacteria MS4 NPDES BA177 CE Turbidity 12.2 Turbidity MS4 NPDES From SR 2220 to 140 LQN' D1sso[vcd Oxygen MS4 NPDES 1641-1-(11.5)c WS-IV NS 4.0 FW Miles I BA181 CE Turbidity 12.2 S BA181 NCE Habitat Degradation MS4 NPDES BA181 NCE Low DO 9.1 Low Dissolved Oxygen WWTP NPDES From 140 to a point 0.8 mile downstream of Durham BB238 F '2003 Low Dissolved Oxygen MS4 NPDES County SR 1107 Turbidity MS4 NPDES New Hope -i-t ek•:(iucludin —New Hope Gre't k Aim of New Hope River Arm tif.B .`Everett:Jordani ake) ^` 16-41-1-(14) WS-IVNS 1,415.7 FW Acres 1 BL14 CE Chlora 73 ND Chlorophyll MS4NPDES From a point 0.8 mile downstream of Durham County SR Chlorophyll a WWTP NPDES 1107 to confluence with Morgan Creek Arm of New (lone River Arm of B. Everett Jordan Lake CAPE FEAR Subbasin 03-06-05 Table 8 CAPE FEAR Subbasin 03-06-05 AU Number Classification Length/Area Aquatic Life Assessment Recreation Assessment Year/ Description AL Rating Station Result Parameter % Exe REC Rating Station Result Stressors Sources New Hope River Arm of B. Everett Jordan Lake (below normal pool elevation 1641-(0.5) WS-IV&B 1,199.8 FW Acres I BL12 CE Chlora 4C N❑ Chlorophyll a MS4 NPDES From source at confluence of Morgan Creek and New Chlorophyll a W WTP NPDES Ilope Creek Ann of B. Everett Jordan Lake (a east -west line across the southern tip of the formed penisula) to Chatham Co 16-41-(3.5)a WS-IV&B 5,673.3 FW Acres I BL13 CE Chlora 14.3 NO Chlorophyll a WWTPNPDES BL13 CF Chlor a 2C Chlorophyll a MS4 NPDES BL13 CE Chlora 27 From Chatham County SR 1008 to Haw River Arm of B. Everett Jordan Lake, Haw River Ntirtlieast Cei k YY u } 1641-I-17-(0.7)a WS-IV NS 3.3 FW Miles I BA197 CE Low DO 11.3 S BA197 NCE Turbidity MS4 NPDES BA197 CE Turbidity 14.E BA197 NCE Low Dissolved Oxygen MS4 NPDES From US I lwy 55 to Durham Triangle W WTP 16A1-1-17-(0.7)bl WS-IV NS 3.3 FW Miles I BA209 CE Turbidity 10.3 I BA209 CE Turbidity MS4 NPDES BA209 NCE From Durham Triangle WWTP to Kit Creek 16-41-1-17-(0.7)b2 WS-IV NS 3.2 FW Miles I BA210 CE Turbidity 14.E S BA210 NCE Turbidity MS4 NPDES BA210 NCE From Kit Creek to a point 0.5 mile downstream of Panther Creek 1641-1-12-(2) WS-IV NS 3.9 FW Miles I BA178 NCE NR' BA178 NCE Turbidity MS4 NPDES BA178 CE Turbidity 12.2 Low Dissolved Oxygen MS4 NPDES From a point 2.0 miles upstream ofNC I IWY. 54 to New Fecal Coliform Bacteria MS4 NPDES Hope Creek 'White Oak Creek 1641-6-(0.3) C NSW 3.7 FW Miles NR NO Habitat Degradation From source to a point 0.6 mile upstream of Jack Branch BB314 NR '2003 BB314 NR '2003 1641-6-(0.7) WS-IV NS 5.9 FW Miles NR NO Habitat Degradation MS4 NPDES From a point 0.6 mile upstream of Jacks Branch to a BB314 NR '2003 point 0.3 mile upstream ofNC Ilwy 751 BB314 NR '2003 _ CAPE FEAR Subbasin 03-06-05 Table 8 CAPE FEAR Subbasin 03-06-05 AU Number Classification Length/Area Aquatic Life Assessment Recreation Assessment Year/ Description AL Rating Station Result Parameter %Exe REC Rating Station Result Stressors Sources AL - Aquatic Life BF - Fish Community Survey E - Excellent S - Supporting, I - Impaired REC - Recreation BB - Benthic Community Survey G - Good NR - Not Rated BA - Ambient Monitoring Site GF - Good -Fair NR*- Not Rated for Recreation (screening criteria exceeded) BL- Lake Monitoring F - Fair ND -No Data Collected to make assessment S- DEH RECMON P - Poor Results NI - Not Impaired CE-Criteria Exceeded > 10% and more than 10 samples Miles/Acres S- Severe Stress NCE-No Criteria Exceeded FW- Fresh Water M-Moderate Stress S- Salt Water N- Nat urat Aquatic Life Rating Summary S m 18.6 FW Miles NR m 13.9 FW Miles 1 m 21A FW Miles I • m 8,288.8 F W Acres NR a 13.2 FW Miles ND 121.2 FW Miles ND 2,613.6 FW Acres Recreation Rating Summary S m 10.5 FW Miles NR* to 7A FW Miles I m 3.3 FW Miles ND 166.8 FW Miles ND 10,902.4 FW Acres Fish Consumption Rating Summar3 I e 187.9 FW Miles I e 10,902.4 FW Acres CAPE FEAR Subbasin 03-06-05 5.2 Use Support Assessment Summary Use support ratings were assigned for waters in subbasin 03-06-05 in the aquatic life, recreation, fish consumption and water supply categories. All waters are Impaired on an evaluated basis in the fish consumption category because of fish consumption advice that applies to the entire basin.. In the water supply category, all WS classified waters (10,902.4 acres and 124.9 miles) are Supporting on an evaluated basis based on reports from DEH regional water treatment plant consultants. Refer to Appendix X for a complete list of monitored waters and more information on Supporting monitored waters. There were 53.6 stream miles (28.5 percent) and 8,288.8 freshwater acres (76 percent) monitored during this assessment period in the aquatic life category. There were 21.1 miles (11.2 percent) and 8,288.8 acres (76 percent) of Impaired waters in this category. There were also 3.3 miles (1.7 percent) Impaired for recreation in this subbasin. 5.3 Status and Recommendations of Previously and Newly Impaired Waters The following waters were either identified as Impaired in the previous basin plan (2000) or are newly Impaired based on recent data. If previously identified as Impaired, the water will either remain on the state's 303(d) list or will be delisted based on recent data showing water quality improvements. If the water is newly Impaired, it will likely be placed on the 2006 303(d) list. The current status and recommendations for addressing these waters are presented below, and each is identified by an assessment unit number (AU#). Refer to the overview for more information on AUs. Information regarding 303(d) listing and reporting methodology is presented in Appendix VII. 5.3.1 B. Everett Jordan Reservoir New Hope Creek Arm iAU # 16-41-1-(14)] New Hope River Arm [AU # 16-41-(0.5) and (315)al Morgan Creep Arm [AU # 16-41-2-(9.5)1 (Subbasin 03-06-06) Haw River Arm JAU # 16-(37.3) and (37.5)] (Subbasin 03-06-04) 2000 Recommendations The 2000 basin plan recommended that DWQ continue to monitor Jordan Reservoir to assess impacts from increasing wastewater discharges and development in the watershed and to update the NSW strategy for the reservoir and its watershed. Current Status Jordan Reservoir (9,766.5 acres) is Impaired because the chlorophyll a standard was violated at stations in all mainstem segments of the reservoir and because modeling indicated violations of the chlorophyll a standard in the New Hope Creek, Morgan Creek and Haw River Arms of the reservoir. The highest chlorophyll a levels were collected from August to November. Chlorophyll a levels exceeded the standard in 73 percent of samples in the New Hope River Arm and in 13 percent of samples in mid reservoir. Blooms of blue-green algae associated with taste and odor problems in drinking water were observed in July 2003. The reservoir has been eutrophic since 1982. The Beaver Creek, Parkers Creek and White Oak Creek Arms (2,613.5 Chapter 5 — Cape Fear River Subbasin 03-06-05 55 acres) are Not Rated for aquatic life. Data to assess recreation use support were not collected in the reservoir. 2005 Recommendations Refer to Chapter 36 for complete discussions of the Jordan NSW strategy, TMDLs, modeling, monitoring, HB5l 5 and SB 1366. DWQ, with the Jordan stakeholders, will continue to monitor the reservoir to assess water quality changes associated with implementation of the NSW strategies. Segments 16-41-1-(14), 16-41-1-(0.5) and 16-41-2-(9.5) will remain on the 303(d) list. The Haw River and New Hope River Arms will be added to the 303(d) list. TMDLs are currently being developed to address the Impairment in Jordan Reservoir (Chapter 36). 5.3.2 New Hope Creek JAU# 16-41-1-(0.5)a, b, and (I 1.5)a, b and cl 2000 Recommendations The 2000 basin plan recommended that DWQ work with the stormwater programs to help improve water quality in New Hope Creek. DWQ also encouraged smaller facilities to connect to the regional WWTP where possible. Current Status . New Hope Creek [I6-41-1-(0.5)a] from source to Sandy Creek (17.4 miles) is Supporting aquatic life because of a Good -Fair benthic community rating at site 1313324. New Hope Creek [I 6-41-1-(0.5)b and (I 1.5)a] from Sandy Creek to SR 2220 (1.1 miles) is Supporting aquatic life because of a Good -Fair fish community rating at site BF57. The creek had no intolerant species indicating degraded water quality. New Hope Creek [16-41-1-(11.5)b] from SR 2220 to I-40 (3.5 miles) is Impaired for aquatic life because the dissolved oxygen standard was violated in 13 percent of samples and the turbidity standard was violated in 12 percent of samples collected during the assessment period at site BA 177. This segment is Not Rated for recreation because fecal coliform bacteria screening criteria were exceeded at site BA177. DWQ performed a statistical trend analysis at site BA177 using total nitrogen, total phosphorus and total suspended solids data collected from 1990 to 2004. There was a significant decrease in total nitrogen of 0.17 mg/1 per year in New Hope Creek. Downward trends were noted for total phosphorus and total suspended solids, although these trends were not significant. New Hope Creek [16-41-1-(11.5)c] from I-40 to SR 1107 (4 miles) is Impaired for aquatic life because of a Fair benthic community rating at site 136238. The riparian zone was intact at site 1313238, but the banks were steep and eroding and there was little pool and riffle habitat. The stream also contains trash from the surrounding urban watershed. DWQ completed a fecal coliform study in New Hope Creek in 2000 and determined that fecal coliform bacteria did not exceed the standard in this segment. This segment is Supporting recreation because of this sampling. There are many single family NPDES permitted discharges in this watershed that may contribute oxygen -consuming wastes as well as bacteria and nutrients. Chapter 5 — Cape Fear River Subbasin 03-06-05 56 2005 Recommendations DWQ will continue to monitor the New Hope Creek to identify stressors to the benthic community. DWQ will continue to work with Durham stormwater program to pursue funding for BMPs in the New Hope Creek watershed to further decrease nutrient loading into Jordan Reservoir. Further recommendations to protect streams in urbanizing areas and to restore streams in existing urban areas are discussed in Chapter 31. Segment 16-41-1-(11.5)b and c remain on the 303(d) list. Segments 16-41-(0.5)a and b and 16- 41-(11.5)a will be removed from the 303(d) list. TMDLs (Chapter 35) will be developed for identified stressors within 8-13 years of listing. Water Quality Initiatives In 1997, Durham County received a $750,000 CWMTF (Chapter 34) grant to purchase 340 acres of conservation easements along New Hope Creek [16-41-1-(0.5)a] and Mud Creek [16-41-1-10] in this watershed. The Triangle Land Conservancy (Chapter 34) also received a $2,750,000 CWMTF grant to acquire 392 acres along the New Hope Creek Greenway. In 1998, Chapel Hill received a $502,000 CWMTF grant to acquire 105 acres of permanent easements along Dry Creek. In 1999, NCEEP (Chapter 34) received a $582,500 CWMTF grant to stabilize and restore 450 linear feet of Sandy Creek [16-41-1-11] in Duke Forest and to construct a bioretention areas to treat runoff from 25 acres of urban area. This grant also included restoration of 8.2 acres of bottomland hardwood wetlands in the New Hope Creek watershed. The NCEEP completed 3,000 linear feet of stream enhancement in the Sandy Creek watershed. 5.3.3 Northeast Creek [AU # 16-41-1-17-(0.7)a, bl and b2] 2000 Recommendations The 2000 basin plan recommended that DWQ work with the stormwater programs to help improve water quality in Northeast Creek. Current Status Northeast Creek [16-41-1-17-(0.7)a] from US 55 to Durham Triangle WWTP (3.3 miles) is Impaired for aquatic life because the turbidity standard was violated in 15 percent of samples and the dissolved oxygen standard was violated in 11 percent of samples at sites BA197. This segment is Supporting recreation because the fecal coliform bacteria standard was not violated during intensive sampling to assess the standard at site BA197. Northeast Creek [ 16-41-1-17-(0.7)b 1 ] from Durham Triangle WWTP to Kit Creek (3.3 miles) is Impaired for aquatic life because the turbidity standard was violated in 10.3 percent of samples at site BA209. This segment is Impaired for recreation because the fecal coliform bacteria standard was violated during intensive sampling to assess the standard at site BA209. J� I Northeast Creek [16-41-1-17-(0.7)b2] from Kit Creek to downstream of Panther Creek (3.2 miles) is Impaired for aquatic life because the turbidity standard was violated in 15 percent of samples at site BA209. This segment is Supporting for recreation because the fecal coliform bacteria standard was not violated during intensive sampling at site BA209. DWQ developed a fecal coliform bacteria TMDL that was approved by EPA in September 2003. The TMDL recommended a 90 percent reduction in bacteria loading from urban stormwater in Durham (Chapter 35). Chapter 5 -- Cape Fear River Subbasin 03-06-05 57 2005 Recommendations DWQ will continue to monitor Northeast Creek. DWQ will work with Durham stormwater services where possible to help reduce the impacts of stormwater and to reduce bacteria loading by 90 percent. Further recommendations to protect streams in urbanizing areas and to restore streams in existing urban areas are discussed in Chapter 31. All three segments will remain on the 303(d) list. TMDLs (Chapter 35) will be developed for identified stressors within 8-13 years of listing. 5.3.4 Third Fork Creek [AU # 16-41-1-12-(1) and (2)J 2000 Recommendations The 2000 basin plan recommended that DWQ continue to monitor Third Fork Creek to determine the impacts of development in the watershed. Current Status i "AP? �-e 'ZOO(, �,o; Cct) �-► 5}-: Third Fork Creek [16-41-1-12-(1)] from source to 2 miles upstream of NC 54 (5.2 miles) is N Rai on an evaluated basis because Brenntag Southeast Incorporated (NC0086827) failed whole effluent toxicity (WET) tests five times during the last two years of the assessment period. The facility is in the headwaters of Third Fork Creek and instream impacts of these failures could not be assess6d. Chemical leaching at Brenntag may be a potential source of toxicity. Third Fork Creek [16-41-1-12-(2)] from 2 miles upstream of NC 54 to New Hope Creek (3.9 miles) is Impaired for aquatic life because the turbidity standard was violated in 12 percent of samples collected at site BA l78 during the assessment period. This segment is Not Rated for recreation because the fecal coliform bacteria screening criteria were exceeded at site BA178. TMDL Chapter 35) was approved in January 2005 for total suspended solids that 1+rvC.�� z5 re ended a 56 percent reduction in TSS mostly from i e Durham stormwater system. ,in k +Z'/ 2005 Recommendations -TMnL. DWQ will continue to monitor Third Fork Creek. DWQ will work with Durham stormwater services where possible to help reduce the impacts of stormwater. DWQ will determine if intensive sampling is needed to assess the fecal coliform bacteria standard in this creek (Appendix X). The NPDES compliance process will be used to address the significant permit violations noted above. Segment 16-41-1-12-(2) will be added to the 303(d) list. TMDLs (Chapter 35) will be developed for identified stressors within 8-13 years of listing. Water Quality Initiatives The NCEEP completed 3,200 linear feet of stream restoration in this watershed (Chapter 34). Chapter 5 —,Cape Fear River Subbasin 03-06-05 58 5.4 Status and Recommendations for Waters with Noted Impacts The surface waters discussed in this section are not Impaired. However, notable water quality problems and concerns have been documented for some waters based an this assessment. While these waters are not Impaired, attention and resources should be focused on these waters to prevent additional degradation or facilitate water quality improvement. Waters in the following section are identified by assessment unit number (AU#). See overview for more information on AU#s. 5.4.1 Beaver Creek JAU# 16-41-10-(0.5)1 Current Status and 2005 Recommendations Beaver Creek from NC 55 to SR 1141 (6 miles) was not assigned a use support rating during this assessment period. Beaver Creek drains urbanized areas in and around Apex and is likely impacted by runoff. Further recommendations to protect streams in urbanizing areas and to restore streams in existing urban areas are discussed in Chapter 31. Water Quality Initiatives The Town of Apex (Chapter 34) received a $387,000 CWMTF grant to acquire 43.2 acres of riparian tloodplain to add to 81.6 acres already owned by the town as part of a greenway system. 5.4.2 Cub Creek [AU # 16-41-2-10-(0.5)1 Current Status and 2005 Recommendations Cub Creek from the source to downstream of SR 1008 (8 miles) is currently Not Rated for aquatic life on an evaluated basis because Cole Park Plaza (NC0051314) had significant violations of surfactant permit limits, which could have adversely impacted. aquatic life in the creek. The NPDES compliance process will continue to be used to address significant permit violations. 5.4.3 White Oak Creek EAU# 16-41-6-(0.3) and (0.7)] Current Status and 2005 Recommendations White Oak Creek from source to NC 751 (9.6 miles) is Not Rated for aquatic life, and a benthic community rating could not be assigned at site BB314 because the stream dries in summer months. The benthic community was impacted by 2002 drought conditions. The upper portions of White Oak Creek drain urbanized Cary. Further recommendations to protect streams in urbanizing areas and to restore streams in existing urban areas are discussed in Chapter 31. Water Quality Initiatives The Town of Cary (Chapter 34) requires 100-foot buffers on all USGS mapped perennial and intermittent streams. The buffer requirements will help minimize water quality impacts in the White Oak Creek watershed as development proceeds. In 2000, Cary (Chapter 34) received an $86,000 CWMTF grant to produce a greenway feasibility study in the White Oak Creek watershed. In 2001, Cary received a $1,084,000 CWMTF grant to purchase conservation easements along 197 acres of White Oak Creek to be part of a greenway system. Chapter 5 -- Cape Fear River Subbasin 03-06-05 59 5.5 Additional Water Quality Issues within Subbasin 03-06-05 The following section discusses issues that may threaten water quality in the subbasin that are not specific to particular streams, lakes or reservoirs. The issues discussed may be related to waters near certain land use activities or within proximity to different pollution sources. 5.5.1 Jordan Haw River Watershed Nutrient Sensitive Waters Strategy All land uses and discharges of wastewater and stormwater in subbasin 03-06-05 potential] contribute nutrients to Jordan Reservoir to su astns - an - - 5. The reservoir is mpaired for aquatic ecause lorophyll a violated the standard in all segments of the reservoir. Refer t Chapter 36 for ore information on this strategy. K'tjvit";� Mfl't'�Jwn 9 jOYj2'i'— 7-M()L, Chapter 5 — Cape Fear River Subbasin 03-06-05 60 Turbidity and Fecal Coliform TMDL: Haw River, Deep River, Third Fork Creek, and Dan River 1. Introduction This report presents the development of Total Maximum Daily Loads (TMDLs) for four water bodies in North Carolina: Haw River, Deep River, Third Fork Creek, and Dan River. The first three water -bodies are located in the Cape Fear River Basin (CFRB) (Figure 1.1) while the Dan River is located in the Roanoke River Basin (RRB) (Figure 1.2). As identified by the North Carolina Division of Water Quality (DWQ), the impaired segments of the four water bodies are as follows (NCDENR 2003), • The Haw River in the CFRB is impaired due to fecal coliform and turbidity. The impaired segment is located in sub -basin 30602 from NC 87 to NC 49. This section of the river runs approximately 13 miles and is designated as a class C waterl. • The Deep River in the CFRB is impaired due to fecal coliform. The impaired segment is located in sub -basin 30608 from SR 1113 to SR 1921. This section of the stream runs approximately 7 miles and is designated as a class WS-IV waterl. • The Third Fork Creek in the CFRB is impaired due to turbidity. The impaired segment is located in sub -basin 30605 from 2.0 miles upstream of NC Hwy 54 to New Hope Creek. This section of the stream runs approximately 4 miles and is designated as a class WS-IV waterz. • The Dan River in the RRB is impaired due to turbidity. The impaired segment is located in sub -basin 30203 from a point 0.7 mile upstream of Jacobs Creek to a point of 0.8 mile down stream of Matrimony Creek. This section of the stream runs approximately 14 miles and is designated as a class WS-IV waterl. Section 303(d) of the Clean Water Act (CWA) requires States to develop a list of water bodies that do not meet water quality standards or have impaired uses. The list, referred to as the 303(d) list, is submitted biennially to the U.S. Environment Protection Agency (USEPA) for review. The 303(d) process requires that a Total Maximum Daily Load (TMDL) be developed for each of the waters appearing on Category 5 of the 303(d) list. t Class C waters are protected for secondary recreation, fishing, wildlife, fish and aquatic life propagation and survival, agriculture and other uses suitable for class C. There are no restrictions on watershed development or types of discharges. 2 Class WS-IV waters are used as sources of potable water supply where WS-1, WS-II or WS-III classification is not feasible. WS-IV waters are generally in moderately to highly developed watersheds or Protected Areas, and involve no categorical restrictions on discharges. Turbidity and Fecal Coliform TMDL: Haw River, Deep River, Third Fork Creek, and Dan River r `r' Y i 30 . at � j` .r •y�� 0 30 hlyd fork C+®rk W 60 Mile® Figure 1.1. Upper Cape Fear River Basin showing Haw River, Deep River, and Third Fork Creek and water quality stations along the main water bodies. 4 Turbidity and Fecal Coliform TMDL; Haw River, Deep River, Third Fork Crack, and Dan River t"J"41 Am 0 '\,; ' Third pork Crook Lad Use Mass Barren Land Forest Land N Urban or Built-up Land Water • Outlet �4r � E Su bbas ine County Boundaries a lisle■ Figure 1.5. Mid 70's land use distribution in the Third Fork Creek watershed. 10 Turbidity and Fecal Coliform TMDL: Haw River, Dcep River, Third Fork Creek, and Dan River 5. Third Fork Creek Impairment 5.1. Source Assessment The DWQ staff noticed several developing activities such as land clearing and site preparation for residential buildings, commercial areas, roads, and highways being conducted in the Third Fork Creek watershed. These activities are the main sources of turbidity. Surface runoff carries sediments and solids from these lands to the creek and increases turbidity level. In addition, point sources such as waste water treatment plants (WWTP) and MS4 areas are also responsible for TSS increment in a water body. 5.1.1. NPDES Wastewater Permits There was only one facility, Brenntag Southeast, Inc., under the NPDES program that discharged wastewater to the Third Fork Creek (Table 5.1). The facility was permitted to discharge up to 30 mg/L of TSS daily. Table 5.1. NPDES Wastewater Perinits in the Third Fork Creek * qi r a, 'u F Daily Permitted ~Permitted ., ;= , Limit Permtt?No. Facili ame ,: Flow 1VIGQ; TS$1(m L) NCO086827 Brenntag Southeast, Inc. 0.0144 30 5.1.2. NPDES General Permits All construction activities in the Third Fork Creek watershed that disturb one or more acres of land are subject to NC general permit NCGO10000 and as such are required to not cause or contribute to violations of Water Quality Standards. As stated in Permit NCGO10000, page 2, "The discharges allowed by this General Permit shall not cause or contribute to violations of Water Quality Standards. Discharges allowed by this permit must meet applicable wetland standards as outlined in 15A NCAC 2B .0230 and .0231 and water quality certification requirements as outlined in 15A NCAC 2H .0500". Monitoring requirements for these construction activities are briefly explained in Section 3.1.2. 5.1.3. NPDES Stormwater MS4s The City of Durham in the Third Fork Creek watershed falls under the Phase I NPDES storm water program for MS4. All of the urban lands in the watershed were, therefore, occupied by the city. 49 Turbidity and Fecal Coliform TNIDL: Haw River, Deep River, Third Fork Creek, and Dan River 5.2. Technical Approach As discussed in Section 3.2, a load duration approach was adopted to determine impairment loads under different flow conditions to identify source types, specify assimilative capacity of a stream, and to estimate magnitude of load reduction required to meet the water quality standard. Following paragraphs explains its application for developing turbidity TMDL for the Third Fork Creek. 5.2.1. Endpoint for Turbidity As discussed in Section 3.2.1, total suspended solid (TSS) was selected as a surrogate measure for the Third Fork Creek. In order to observe relationship between TSS and turbidity in the creek, a regression equation between the two parameters was developed using the observed data collected from April 2004 through September 2003 in the ambient station, B3025000. The equation is shown in Equation 5,1, The coefficient of determination between the two parameters was 0.73, suggesting a significant relationship. Y = 0.0068 X z + 0.0827X + 7.7524 R-Square = 0.73----------------------(5.1) Where, Y = TSS in mg/l and X = turbidity in NTU. Equation 5.2 suggests that the Third Fork Creek yielded approximately 7.75 mg/L of TSS during natural condition (NTU = 0). However, the creek showed a polynomial relationship between TSS and turbidity. Therefore, the corresponding TSS value at the turbidity standard of 50 NTU was 29 mg/L. 5.2.2. Flow Duration Curve Daily stream data collected from .January 1982 through September 2003 at the USGS gage station, 0209741955, at SR1100 near Glenlce, was used to develop flow duration curves. The gage station drains about 21 sq. miles of the Northeast Creek watershed. The watershed area is slightly bigger than the Third Fork Creek watershed (16.5 sq mi). The watershed is almost similar in characteristic and is adjacent to the Third Fork Creek at the Eastern side. Therefore, flows of the Third Fork Creek were estimated using "area ratio method." In the method, the area ratio is first estimated by dividing the area of the Third Fork Creek watershed by the area of the Northeast Creek watershed. The flows of the Northeast Creek are then multiplied by the ratio to estimate the flows for the Third Fork Creek. The flow duration curve for the Third Fork Creek 50 Turbidity and Fecal Colifortn TMDL: Haw River, Deep River, Third Fork Creek, and Dan River watershed is shown in Figure 5.1. Flow statistics as generated by the curves are presented in Table 5.2. Table 5.2: Flow Statistics for the Third Fork Creek, High Flow Typ>cal Flow t, a;(< 10`h percentile) WiWai�gfttii4MMlaw and 30`h (+Between 30`and` ercenkila 47 -2616 cfs 5 — 47 cfs 3 — 5 cfs 1 —3 cfs 10000 1000 100 0 10 U.1 0. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Percent flow exceeded High Transitional Typical Flow Low Flow Flaw Flow Figure 5.2. Flow Duration Curve for the Third Fork Creek. Flows from the Northeast Creek at USGS 0209741955 were used to estimate flows for the Third Fork Creek. The flow duration curve was used to determine the seasonality and flow regimes during which the exceedances of the pollutants occurred. It was also used to determine maximum daily pollutant load based on the flow duration and applicable standard. 5.2.3. Load Duration Curve As discussed in Section 3.2.4, a load duration curve is developed by multiplying the flow values along the flow duration curve by the pollutant concentrations and the appropriate conversion factors. As seen in Figure 5.2, allowable and existing loads are plotted against the flow 51 Turbidity and Fecal Coliform TMDL: Haw River, Deep River, Third Fork Creek, and Dan River recurrence interval. The allowable load is based on the water quality numerical criteria, margin of safety, and flow duration curve. Following paragraphs discusses procedures to estimate endpoints for turbidity in the Third Fork Creek in order to identify assimilative capacity of the creek in each flow conditions and to identify the flow regime during which exceedances occur. 5.2.4.1. Turbidity Assimilative Capacity Existing TSS loads to the Third Fork Creek was determined by multiplying the observed TSS concentration by the flow observed on the date of observation and converting the result to daily loading values. The assimilative capacities of the water bodies were determined by multiplying the TSS concentration that is equivalent to a turbidity value of 50 NTU by the full range of measured flow values. Figure 5.2 present the calculated load, (scatter plot) power line (dotted line), and the TMDL target loading (solid line) for the creek. r. 1000 N 100 ❑ 2 10 -- !] V 0 Cl Ell CO0.1 0�p — �" 0.01 0 0 0 o a o a o o a o 0 0 0 0 0 0 0 0 0 0 o 0 0 o a o 0 r lV M Nt ui 0 0 0 0 0 co 1- Go rn o C Dnrnnh_C Intu_Cvrnnrinel ❑ Existing load -Allowable load • Summer Existing Load - - - Power (Existing load) Figure 5.2. TSS Load duration curve for Third Fork Creek at the coalition station, B3025000, from April 2000 through September 2003. 52 Turbidity and Fecal Coliform TMDL: Flaw River, Deep River, Third Fork Creek, and Dan River Except during low flow periods, the assimilative capacity of the Third Fork Creek exceeded the targeted values (Figure 5.2). The result, therefore, suggests that non -point sources alone could have increased turbidity level in the creek. Furthermore, the power line that represented average existing TSS loads clearly explicated that' the TSS loads under natural background condition did not exceed the turbidity standard of 50 NTU (29 mg/L) in the Third Fork Creek (Figure 5.2). The power line. passed underneath the targeted line except during high flow period (<10% flow exceeded), which is indeed unmanageable and hence is excluded in the TMDL estimation in this study. 5.3. Total Maximum Daily Loads (TMDL) Sections 5.2 described the processes and rationale to identify the endpoints, assimilative capacity, potential sources, and target loadings for each pollutant in the Third Fork Creek watershed. These efforts formed the basis for the TMDL process. The key components required by the TMDL guidelines to set the final TMDL allocation for the watershed is defined by the equation 5.2. TMDL = Y,WLAs + YLAs + MOS---------------(5.2) Where, WLA is waste load allocation (point source), LA is load allocation (non -point source), and MOS is marginal of safety. Detail explanation of the equation is given in Section 3.3. Following sections describe the key components required by the TMDL guidelines to set the final TMDL allocation for the Watershed. 5.3.1. Margin of Safety (MOS) The Margin of Safety was explicitly included in following TMDL analysis by setting the TMDL target at 10 percent lower than the water quality target for turbidity. 5.3.2. Target Reduction To determine the amount of turbidity reduction necessary to comply with the water quality criteria, exceedances of the estimated standard (29 mg TSS/L) were identified within the 10`h to 95`h percentile flow recurrence range. A power curve through the data point violating the water quality criterion was overlaid on the graph (Figure 5.3). The power curve equation is presented 53 Turbidity and Fecal Coliform TMDL: Haw River, Deep River, Third Fork Creek, and Dan River in Equation 5.2. The correlation coefficient, R-Square, for the power curve is 0.71; thus suggesting a reasonable fit of the curve. Y = 0.3208 # X "1 "') R-Square = 0.71---------------------------(5.2) Where, Y = Turbidity (mg/L) and X = Percent Flow Exceeded. The criteria violations occurred through out the typical flow regime (Figure 5.3). As described in Section 3.3, the loading estimates based on the power curve are presented in Appendix 4. Approximately 53 percent reduction in turbidity is required in order to meet the water quality standard and to account for the 10 percent of MOS. A summary of reductions required is provided in Table 5.3. Table 5.3. Reduction Required for TSS in the Third Fork Creek Pollutants Target Existing Load ' Allowale. Load Reduction �Requircd . , s TSS' < 26 mg/L, 1.58 tons/day 0.75 tons/day 53 % 'TSS is used as a surrogate variable for turbidity' 10 'a y � O -c 0 J � N H 0.1 10.00% 30.00% 50.00% 70.00% 90.00% Percent Flow Exceeded Allowable Load ■ Existing Load Violated 7 Power (Existing Load Violated) Figure 5.3. Load duration curve showing allowable and existing loads violation of the Third Fork Creek. 54 a Turbidity and Fecal Coliforni TMDL: Haw River, Deep River, Third Fork Creek, and Dan River 5.3.3. TMDL Allocation As identified by the above load duration curve method, significant amounts of TSS are required to be reduced in the Third Fork Creek. In order to meet the TMDL objectives, the reduction should be targeted towards non -point sources and MS4 areas. 5.3.3.1. Waste Load Allocation (WLA) All TSS transported from the MS4 areas and waste load facility, Brenntag Southeast, were assigned to the WLA components. The relative loading rates from the MS4 areas are discussed in Section 3.3.3. A summary of the report and a description of method that was used to estimate relative percent contribution of TSS from the urban and rural sources are presented in Appendix 11.3. The estimated relative percent contribution from the MS4 and rural areas (non -point sources including non-MS4 area) are presented in Table 5A, Table 5.4. Relative TSS Contribution Rates for the Third Fork Creek. Pollutants �. „Load t�-v -d'' .M. �:. ��He.'.�i , . _" � 'V> t o, w from,MS4'areas {./o) L 1 �I-�{ a' / +y �Y. g F ,' Loa�dqIY, fro,yyyynri other areas(/o) :.I+R Y'!gtli'Ff . ♦ S': TSS 48 52 The assimilative capacity determined in Section 5.2.3 was split based on the relative contributions presented in Table 5.4 to determine the allocation for the MS4 areas. The results of these calculations are summarized in Table 5.5. The WLA associated with construction and other land management activities, as discussed in Section 5.1.2, is equivalent to the surface water quality standard for turbidity in that any construction activity cannot cause or contribute to a violation of the water quality standard. As discussed, these WLAs are and will be expressed as BMPs in the general or individual constriction permits rather than as numeric effluent limits. 5.3.3.2. Load Allocation (LA) All TSSloadings from non -point sources such as non-MS4 urban land, agriculture land, and forested land were reported as LAs. The relative loading rates from these areas were determined using the similar procedures as described in Section 3.3.2. (See also Appendix 1 1.3.) The 55 Turbidity and Fecal Coliform Ttvl DL: Haw River, Deep River, Third Fork Creek, and Dan River estimated relative percent contribution of TSS from the non -point sources is presented in Table 5.5. Table 5.5. Estimated TMDL and Load Allocation for TSS for the Third Fork Creek, Watershed. Pollutants 'Existing nstruc"t'NPWiA' is15c LVI®STI'vIDL Activltie5. d a,, ; r.'. nl';° TSS 1.58 50 NTU 0.002 0,36 0.36 0.39 Explicit 0.75 (tons/day) - 10 % 'WLA = MS4 -+- NPDES (including construction activities) 5.3.3.3. Study Limitation The available land cover for this study is outdated and fails to represent current land use condition. Therefore, the estimation of WLA in Table 5.5 is not authoritative. The primary focus of efforts to minimize future impairment should be on the percent reductions and control of sources identified in the Source Assessment (see § 2). 5.3.4. Critical Condition and Seasonal Variation According to the load duration curve (Figure 5.2), the greatest frequency of exceedances of turbidity occurred during high -flow periods throughout the season. The result shows that wet weather under high -flow period is the critical period for turbidity in the Third Fork Creek. M