The National Pollution Discharge Elimination System (NPDES), established through the Federal Water Pollution Control Act (FWPCA) Amendments of 1972 (later amended and known collectively as the Clean Water Act), regulates water quality by requiring a permit for point source pollution discharges to waters of the United States. Point sources are pollution sources from a specific, defined point such as a pipe or manmade ditch. Under NPDES, all facilities which discharge pollutants from any point source into waters of the United States are required to obtain a permit. Early pollution prevention successfully focused on point sources such as industrial sites and sewage treatment plants. In 1990, the NPDES premitting system moved on to include point sources of stormwater runoff pollution.
Stormwater pollution may include sediments, nutrients, acids and salts, heavy metals, toxic chemicals and pathogens which all eventually affect lakes, ponds and streams. The regulatory bottom line for this system focuses on reducing water pollution to the Maximum Extent Practicable (MEP), overall protection of water quality, and satisfying the appropriate water quality requirements of the Clean Water Act.
Although not regulated under NPDES, non-point source pollution, or runoff pollution, is a significant source of water quality impairment. Non-point source pollutants are picked up and carried by rainfall and snow melt. Non-point source pollution can come from a potentially wide area and a delineated point of the pollution discharge can't be identified.
The NPDES is administered through the Nebraska Department of Environmental Quality (NDEQ) in Nebraska. There have been two phases of implementation for stormwater permitting.
The Phase I Stormwater Rule (1990) required NPDES permits for stormwater discharges from:
- Medium and Large Municipal Separate Storm Sewer Systems (MS4s) in cities with a population of over 100,000
- 11 industrial categories
- Construction activities disturbing 5 or more acres (construction activity is one of the 11 industrial categories but permits for construction activity have specific requirements)
The Phase II Stormwater Rule (early 2003) extended the requirement for NPDES stormwater permit coverage to include:
- Small Municipal Separate Storm Sewer Systems (MS4s) located within urbanized areas based on the latest Census.
- Small MS4s located outside of an urbanized area if the permitting authority determines their stormwater discharges could have an adverse impact on water quality.
- Small MS4s located outside of an urbanized area designated by the permitting authority as contributing substantially to the pollutant loading of a physically interconnected MS4 regulated by the NPDES stormwater program. In other words, the small MS4 directly discharges into the regulated MS4.
Regulated MS4s in Nebraska now include Douglas County, Dakota County, Sarpy County, Beatrice, Bellevue, Boy's Town, Columbus, Dakota City, Fremont, Grand Island, Hastings, Kearney, La Vista, Lexington, Lincoln, Norfolk, North Platte, Omaha, Papillion, Ralston, Scottsbluff, South Sioux City, Offutt Air Force Base, University of Nebraska-Lincoln, Nebraska Department of Roads. The Phase II Rule is having a significant impact in many areas of Nebraska that had previously not focused on stormwater management improvements. There are six minimum control measures required by the NPDES permitting program for all Phase II communities and entities:
- Public Education and Outreach
- Public Participation and Involvement
- Illicit Discharge Detection and Elimination
- Construction Site Runoff Control
- Post-Construction Runoff Control
- Pollution Prevention and Good Housekeeping
- In addition, Phase II also covers discharges from construction activity which disturbs between 1 and 5 acres (or less than 1 acre if part of a larger common plan of development or sale). Because of the relatively small area of disturbance, most construction sites must be in compliance with state and local requirements for minimized erosion and limited sediment movement.
Additional information on Nebraska stormwater regulations and policies can be found at the following links:
Information presented within the Stormwater Management section of this Water Web site has been reviewed by the University of Nebraska Stormwater Management Team. Please contact Katie Pekarek, Kelly Feehan, or Thomas Franti with questions.