Industrial stormwater refers to water runoff related to certain business activities identified in the stormwater regulations of the Clean Water Act. The permits related to these types of activities are known as Multi-Sector General Permits. Some businesses in Denton are required to have these permits, use the decision tree and the questions and answers section to determine if your business needs a permit.
Determine whether your facility or site discharges to a municipal separate storm sewer system (MS4) or to waters of the U.S.
If your facility discharges to one or both go to Step 2, otherwise no stormwater permit is needed.
What is a Municipal Separate Storm Sewer System (MS4)?
A MS4 is a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains):
- Owned or operated by a state, city, county, district, or other public body, including special districts under state law such as a sewer district, flood control district or drainage district that discharges into waters of the U.S.
- Designed or used for collecting/conveying stormwater
- Which is not a combined sewer
- Which is not part of a publicly-owned treatment works
Industrial operators may ask their municipal government whether their facility discharges into an MS4 or into a sanitary sewer, which is not covered by the stormwater regulations.
Surface water in the state of Texas includes lakes, bays, ponds, impounding, reservoirs, springs, rivers, streams, creeks, estuaries, marshes, inlets, canals, the Gulf of Mexico inside the territorial limits of the state, and all other bodies of surface water, natural or artificial, inland or coastal, fresh or salt, navigable or non-navigable, and including the beds and banks of all watercourses and bodies of surface water, that are wholly or partially inside or bordering the state or inside the jurisdiction of the state (Section 26.001 of the Texas Water Code).
Determine if your facility's industrial activities fall within one of the eleven Categories of Industrial Activities. If your activities are listed, go to Step 3, otherwise no permit is needed. Industrial stormwater permits are required for specific types of activities. Some categories are defined by a Standard Industrial Classification (SIC) code and others are defined by a narrative description. If any of the following categories apply to your business, you may be required to obtain permit coverage.
Which industries are regulated?
- 40 CFR Subchapter N Industries: facilities subject to stormwater effluent limitations guidelines
- Heavy Industry: SIC 24 (except 2434), 26, (except 265 and 267), 28 (except 283), 311, 32 (except 323), 33, 3441, and 373 3) Mineral Industry: SIC 10, 12, 13, and 14
- Hazardous Waste Industry: hazardous waste treatment, storage, or disposal facilities
- Landfill Industry: industrial waste landfills, land application sites, and open dumps
- Recycling Industry: metal scrap yards, battery reclaimers, salvage yards, automobile junkyards, and SIC 5015 and 5093
- Power Generation Industry: steam electric power, including coal handling sites
- Transportation Industry: SIC 40, 41, 42 (except 4221- 4225), 43, 44, 45, 5171 that have vehicle maintenance shops, equipment cleaning operations, or airport deicing operations
- Wastewater (Municipal or Domestic Sewage) Treatment Industry
- Construction Industry: activities including clearing, grading, and excavation (NOTE: TCEQ has a separate permit for Construction Activities)
- Light Industry: SIC 20, 21, 22, 23, 2434, 25, 265, 267, 27, 283, 285, 30, 31 (except 311), 323, 34 (except 3441), 35, 36, 37 (except 373), 38, 39, 4221, 4222, and 4225
Determine if the listed facility or site may qualify for an exemption under the conditional no exposure exclusion and/or the ISTEA exemption. Facilities that can certify to having a condition of no exposure may be exempted from permit requirements upon completing and submitting a No Exposure Certification Form. If the facility cannot certify that a condition of exposure exists, then the facility must obtain coverage under and comply with, a stormwater permit.
No exposure means all industrial materials and activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt and/or run-off. Industrial materials or activities include, but are not limited to, material handling equipment or activities, industrial machinery, raw materials, intermediate products, byproducts, final products, or waste products.