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HomeMy WebLinkAboutChapter 14 Chapter 14 Wastewater and Stormwater Programs 14.1 NPDES Wastewater Discharge Permit Summary Discharges that enter surface waters through a pipe, ditch or other well-defined point of discharge are broadly referred to as 'point sources'. Wastewater point source discharges include municipal (city and county) and industrial wastewater treatment plants and small domestic wastewater treatment systems serving schools, commercial offices, residential subdivisions and individual homes. Stormwater point source discharges include stormwater collection systems for municipalities that serve populations greater than 100,000 and stormwater discharges associated with certain industrial activities. Point source dischargers in North Carolina must apply for and obtain a National Pollutant Discharge Elimination System (NPDES) permit. Discharge permits are issued under the NPDES program, which is delegated to DWQ by the Environmental Protection Agency. The primary pollutants associated with point source discharges are: * oxygen-consuming wastes, * nutrients, * color, and * toxic substances including chlorine, ammonia and metals. Currently, there are 77 permitted wastewater discharges in the Roanoke River basin. Table 14 provides summary information (by type and subbasin) about the discharges. Various types of dischargers listed in the table are described in the inset box. Facilities are mapped in each subbasin chapter. For a complete listing of permitted facilities in the basin, refer to Appendix VI. Types of Wastewater Discharges Major Facilities: Wastewater Treatment Plants with flows ≥1 MGD (million gallons per day); and some industrial facilities (depending on flow and potential impacts to public health and water quality). Minor Facilities: Facilities not defined as Major. 100% Domestic Waste: Facilities that only treat domestic-type waste (from toilets, sinks, washers). Municipal Facilities: Public facilities that serve a municipality. Can treat waste from homes and industries. Nonmunicipal Facilities: Non-public facilities that provide treatment for domestic, industrial or commercial wastewater. This category includes wastewater from industrial processes such as textiles, mining, seafood processing, glass-making and power generation, and other facilities such as schools, subdivisions, nursing homes, groundwater remediation projects, water treatment plants and non-process industrial wastewater. The majority of NPDES permitted wastewater flow in the Roanoke River basin is from minor municipal wastewater treatment plants (WWTP). Nonmunicipal discharges also contribute substantial wastewater flow into the Roanoke River basin. Facilities, large or small, where recent data show problems with a discharge are discussed in each subbasin chapter. Chapter 14 – Wastewater and Stormwater Programs 143 Table 14 - Summary of NPDES Dischargers and Permitted Flows for the Roanoke River Basin (as of 04/21/05) Roanoke River Subbasin Facility Categories 01 02 03 04 05 06 07 08 09 10 Total Total Facilities 21 10 11 4 7 3 10 0 8 3 77 Total Permitted Flow (MGD) 1.29 5.37 20.26 0.66 26.02 6.00 41.69 0.0 85.98 1.30 188.57 Major Discharges 1 1403130 2 116 Total Permitted Flow (MGD) 0.0 4.5 19.2 0.0 26.02 6.0 37.54 0.0 84.5 1.15 178.91 Minor Discharges 20 9 7 4 4 2 7 0 6 2 61 Total Permitted Flow (MGD) 1.29 0.87 1.06 0.66 0.01 0.0036 4.15 0.0 1.48 0.15 9.67 100% Domestic Waste 14 3 4 1 1 1 2 0 0 0 26 Total Permitted Flow (MGD) 0.63 0.07 0.05 0.02 0.01 0.0036 0.13 0.0 0.0 0.0 0.91 Municipal Facilities 2 2221140 4 220 Total Permitted Flow (MGD) 0.6 5.28 14.5 0.63 5.0 6.0 9.77 0.0 3.03 1.3 46.11 Nonmunicipal Facilities 19 8 9 2 6 2 6 0 4 1 57 Total Permitted Flow (MGD) 0.69 0.10 5.76 0.03 21.02 0.0036 31.93 0.0 82.95 0.0 142.48 14.2 DWQ Stormwater Programs There are several different stormwater programs administered by DWQ and local jurisdictions. One or more of these programs affects many communities in the Roanoke River basin. The goal of the DWQ stormwater discharge programs is to prevent pollution from entering the waters of the state via stormwater runoff. These programs try to accomplish this goal by controlling the source(s) of pollutants. These programs include NPDES Phase I and II, HQW/ORW stormwater requirements, and requirements associated with the Water Supply Watershed Program. Local governments that are or may be affected by these programs are presented in Table 15. 14.2.1 NPDES Phase I Phase I of the EPA stormwater program started with Amendments to the Clean Water Act (CWA) in 1990. Phase I required NPDES permit coverage to address stormwater runoff from medium and large stormwater sewer systems serving populations of 100,000 or more. There are no NPDES Phase I stormwater permits issued to communities in the basin. Phase I also had requirements for eleven categories of industrial sources to be covered under stormwater permits. Industrial activities which require permitting are defined in ten categories ranging from sawmills and landfills to manufacturing plants and hazardous waste treatment, storage or disposal facilities. Construction sites disturbing greater than five acres were also 144 Chapter 14 – Wastewater and Stormwater Programs required to obtain an NPDES stormwater permit under Phase I of the EPA stormwater program. Excluding construction stormwater general permits, there are 106 general stormwater permits and 6 individual stormwater permits. Refer to the subbasin chapters for more information on stormwater programs and permits and a complete listing of individual permits in Appendix VI. 14.2.2 NPDES Phase II The Phase II stormwater program is an extension of the Phase I program that expands permit coverage to include smaller municipalities below 100,000 populations. The local governments permitted under Phase II are required to develop and implement a comprehensive stormwater management program that includes six minimum measures. 1. Public education and outreach on stormwater impacts; 2. public involvement/participation; 3. illicit discharge detection and elimination; 4. construction site stormwater runoff control; 5. post-construction stormwater management for new development and redevelopment; and 6. pollution prevention/good housekeeping for municipal operations. Construction sites greater than one acre will also be required to obtain an NPDES stormwater permit under Phase II of the EPA stormwater program in addition to erosion and sedimentation control approvals. Those municipalities and counties required to obtain a NPDES stormwater permit under the Phase II rules are identified using 1990 US Census Designated Urban Areas and the results of the 2000 US Census. Based on federal census data, EPA identified 123 cities, including, and 33 counties in North Carolina that would be required to obtain permits for stormwater management. The EPA delegated Phase II implementation to each state and then in 1999 the Division of Water Quality and the Environmental Management Commission (EMC) initiated a rulemaking process. Stormwater Management Rule Update: In 2002, the EMC adopted temporary stormwater rules and by 2003 had adopted permanent rules that were to become effective August 1, 2004. In early 2004, the Rules Review Commission (RRC) objected to the rules for failure to comply with the Administrative Procedures Act and lack of statutory authority. The EMC challenged the decision of the RRC in court (EMC v. RRC 04 CVS 3157). A Wake County Superior Court ruled in the EMC’s favor and the RRC subsequently approved the EMC’s rules. However, while the case was pending the legislature enacted a separate set of requirements in 2004 that were designed to replace the EMC rules. These rules include NPDES stormwater rules covering owners and operators of storm sewer systems and State stormwater rules covering activities in urbanizing areas. The EMC amended the rules at their November 10, 2005 meeting to address objections raised by the RRC at their October 2005 meeting. The inconsistency between the legislative requirements and the EMC rules necessitated consideration of Senate Bill 1566 in the 2006 short session. The legislature approved Session Law 2006-246, Senate Bill 1566 in 2006. Chapter 14 – Wastewater and Stormwater Programs 145 Senate bill 1566 provides that development projects in Phase II municipalities and counties that cumulatively disturb one acre or more of land must comply with the post-construction stormwater standards set out in the bill. The bill sets out criteria whereby unincorporated areas of counties will be subject to Phase II requirements. Under these criteria 25 counties are fully covered, while 8 counties have portions that are subject to the stormwater requirements. The bill also provides a designation and petition process by which additional local governments and other entities may be required to obtain a stormwater management permit. The bill sets out stormwater controls that are based on a project’s level of density and its proximity to Shellfish Resource Waters. Shellfish Resource Waters are waters classified by the EMC as Class SA waters (shellfish growing waters) that contain an average concentration of 500 parts per million of natural chloride ion (saltwater). The Water Quality Committee (WQC) met in November 2006 and directed DWQ Staff to return in January 2007 WQC meeting with proposed amendments to the State Stormwater Rules. These rules will extend the coastal post-construction stormwater controls in Session Law 2006- 246 to all 20 Coastal Counties. Low Density Projects Development projects that are located within one-half mile of and draining to Shellfish Resource Waters are considered low density if they contain no more than 12 percent built-upon area. A project that is not located within one-half mile of Shellfish Resource Waters is a low density project if it contains no more than 24 percent built-upon area or no more than two dwelling units per acre. Low density projects must use vegetated conveyances to the maximum extent practicable to transport stormwater runoff from the project. High Density Projects Projects that are located within one-half mile of and draining to Shellfish Resource Waters are considered high density if they contain more than 12 percent built-upon area. A project that is not located within one-half mile of Shellfish Resource Waters is a high density project if it contains more than 24 percent built-upon area or more than two dwelling units per acre. High density projects must use structural stormwater management systems that will control and treat runoff from the first one inch of rain unless the project is in a coastal county, in which case the project must use structural stormwater management systems that will control and treat runoff from the first one and one-half inches of rain. In addition, projects that are located within one- half mile and draining to Shellfish Resource Waters must control and treat the difference in the stormwater runoff from the pre-development and post-development conditions for the one-year twenty-four hour storm as well as meet certain design standards. Implementation The bill provides an implementation schedule that requires regulated entities to apply for an NPDES stormwater management permit within 18 months of being notified that it is a regulated entity subject to the requirements of this act. A regulated entity must implement its post- 146 Chapter 14 – Wastewater and Stormwater Programs construction program no later than 24 months from the date the permit is issued and fully implement its permitted program within five years of permit issuance. City of Jacksonville and Onslow County have both submitted applications for Phase II. The bill authorizes the EMC to adopt Phase II stormwater management rules. If the EMC does adopt rules, the rules must be substantially identical to the provisions of this act and will be automatically subject to review by the General Assembly and not subject to review by the RRC. The bill became effective retroactively to July 1, 2006. Major Post-Construction Stormwater Controls in SL 2006-246 Shellfish Resource Waters* (SA Waters w/ > 500 ppm chlorides) SA Designated Waters – Not Shellfish Resource Waters* Coastal County – Not SA Designated Waters Non – Coastal County Low Density Threshold 12% 24% 24% 24% Storm Design for High Density Difference in pre and post- development for 1-yr, 24- hour storm** Runoff from first 1.5 inches of rain Runoff from first 1.5 inches of rain Runoff from first 1 inch of rain Setback 30 feet 30 feet 30 feet 30 feet Other Controls No new points of s/w discharge No increase in rate, volume, or capacity in existing conveyances Infiltration up to 1-yr, 24-hr storm Diffuse flow in excess of 1-yr, 24-hr storm No new points of s/w discharge No increase in rate, volume, or capacity in existing conveyances Infiltration up to 1-yr, 24-hr storm Diffuse flow in excess of 1-yr, 24-hr storm *These controls apply within ½ mile and draining to these waters. **Amount of Runoff that would need to be controlled in inches for the difference in pre- and post-development conditions for the 1-year, 24-hour storm. For additional information on stormwater programs please go to http://h2o.enr.state.nc.us/su/ 2006 Recommendations DWQ recommends that the local governments that will be permitted under Phase II develop programs that go beyond the six minimum measures. Implementation of Phase II, as well as the other stormwater programs, should help to reduce future impacts to streams in the basin. Local governments, to the extent possible, should identify sites for preservation or restoration. DWQ and other NCDENR agencies will continue to provide information on funding sources and technical assistance to support local government stormwater programs. 14.2.3 State Stormwater Program The State Stormwater Management Program was established in the late 1980s under the authority of the North Carolina Environmental Management Commission (EMC) and North Carolina General Statute 143-214.7. This program, codified in 15A NCAC 2H .1000, affects development activities that require either an Erosion and Sediment Control Plan (for disturbances Chapter 14 – Wastewater and Stormwater Programs 147 of one or more acres) or a CAMA major permit within one of the 20 coastal counties and/or development draining to Outstanding Resource Waters (ORW) or High Quality Waters (HQW). The State Stormwater Management Program requires new developments to protect these sensitive waters by maintaining a low density of impervious surfaces, maintaining vegetative setbacks, and transporting runoff through vegetative conveyances. Low-density development thresholds vary from 12-30 percent built-upon area (impervious surface) depending on the classification of the receiving stream. If low-density design criteria cannot be met, then high- density development requires the installation of structural best management practices (BMPs) to collect and treat stormwater runoff from the project. High density BMPs must control the runoff from the 1 or 1.5-inch storm event (depending on the receiving stream classification) and remove 85 percent or 90 percent of the total suspended solids. Current Status Table 15 shows the communities in the Roanoke River basin where permits may be required under the state stormwater management program. All development in the three coastal counties requiring an Erosion and Sediment Control Plan (for disturbances of one or more acres) or requiring a CAMA major permit must obtain a stormwater permit. 2006 Recommendations DWQ will continue implementing the state stormwater program with the other NCDENR agencies and local governments. Local governments should develop local land use plans that minimize impervious surfaces in sensitive areas. Communities should integrate state stormwater program requirements, to the extent possible, with other stormwater programs in order to be more efficient and gain the most water quality benefits for protection of public health and aquatic life. 14.3 Water Supply Watershed Stormwater Rules Current Status The purpose of the Water Supply Watershed Protection Program is to provide a proactive drinking water supply protection program for communities. Local governments administer the program based on state minimum requirements. There are restrictions on wastewater discharges, development, landfills and residual application sites to control the impacts of point and nonpoint sources of pollution. The program attempts to minimize the impacts of stormwater runoff by utilizing low-density development or stormwater treatment in high-density areas. All communities in the Roanoke River basin in water supply watersheds have EMC approved water supply watershed protection ordinances. 2006 Recommendations DWQ recommends continued implementation of local water supply protection ordinances to ensure safe and economical treatment of drinking water. Communities should also integrate water supply protection ordinances with other stormwater programs, to the extent possible, in order to be more efficient and gain the most water quality benefits for both drinking water and aquatic life. 148 Chapter 14 – Wastewater and Stormwater Programs Table 15 - Communities in the Roanoke River Basin Subject to Stormwater Requirements Local Government NPDES Phase I and Phase II State Stormwater Program Water Supply Watershed Stormwater Requirements Municipalities Askewville X Aulander Danbury X Eden Likely in the Future X Garysburg Gaston X Halifax Hamilton Hassell Henderson Hobgood X Jackson Jamesville X Kelford X Kernersville Phase II X Lewiston Woodville Littleton Macon Madison X Mayodan X Middleburg Milton Norlina Oak City Plymouth X Reidsville Likely in the Future X Rich Square Roanoke Rapids Likely in the Future X Roxobel X Roxboro X Rural Hall Phase II X Scotland Neck Stokesdale X Stoneville X Chapter 14 – Wastewater and Stormwater Programs 149 Stovall Walkertown Phase II, has applied for a waiver from permit requirements X Walnut Cove X Weldon Wentworth Williamston Windsor X Yanceyville X Counties Beaufort A coastal county Bertie A coastal county Caswell X Forsyth Phase II, in Process X Granville X Guilford Phase II, in Process X Halifax X Martin X Northampton X Orange Phase II X Person X Rockingham X Stokes Phase II X X Surry X Vance X Warren Washington A coastal county 150 Chapter 14 – Wastewater and Stormwater Programs