►What is the National Pollutant Discharge Elimination System (NPDES) Storm Water Quality Management Program?
►What is stormwater, and why is it important?
►What should not enter a storm drain?
►What may enter a storm drain?
►What can I do to reduce pollution in storm water runoff?
►What are Best Management Practices (BMPs)?
►Glossary of Common Stormwater Terms
What is the National Pollutant Discharge Elimination System (NPDES) Storm Water Quality Management Program?
Mandated by Congress under the Clean Water Act, the NPDES Storm Water Quality Management Program is a comprehensive national program for addressing urban sources of storm water discharges which adversely affect the quality of our Nation's waters. The Program uses the NPDES permitting mechanism to require the implementation of controls designed to prevent harmful pollutants from being washed by storm water runoff into local water bodies.
What is stormwater, and why is it important?
Stormwater is water from rain or melting snow that does not soak into the ground. It flows from rooftops, over paved areas and bare soil, and through sloped lawns. As it flows, this stormwater runoff collects and transports the following pollutants:
•Automobile fluids (oil, grease, gasoline, antifreeze)
•Deicing products (road salt and fertilizers)
•Grass clippings, leaves, and other yard waste
Storm drains efficiently convey runoff from your neighborhood to the nearest body of water. Consider a rooftop connected to a gutter system that is adjacent to a sidewalk. This sidewalk may drain to a concrete-lined storm drain leading to a stream. This system can quickly transport pollutants into our rivers and streams. This series of connected impervious areas may be thought of as a "stormwater superhighway". Contrary to popular belief, storm drains do not carry stormwater to wastewater treatment plants - storm drains directly lead to streams and eventually the ocean.
Polluted stormwater degrades streams, rivers, ponds, wetlands, estuaries, sounds, and bays. Soil clouds water and deteriorates habitat for fish and plants. Nutrients such as nitrogen and phosphorus promote the growth of algae, which crowd out other aquatic life. Toxic chemicals, such as antifreeze and oil from leaking cars, carelessly applied pesticides, and zinc from galvanized metal gutters and downspouts, also threaten the health of fish and other aquatic life. Bacteria and parasites from pet waste and leaking septic tanks can make lakes and the ocean unsafe for wading and swimming after storms.
Across the country, public officials are directing their pollution control efforts to stormwater management in urban and rural areas. Preventing stormwater pollution presents unique challenges since pollutants come from many sources (see table below). Pollutants are carried by runoff from every street, parking lot, sidewalk, driveway, yard, and garden. The problem can only be solved with everyone's help!
Common Sources of Stormwater Pollutants
sand, and clay
sites; bare spots in lawns and gardens; wastewater from sediment
and other debris; washing cars and trucks on driveways or parking
lots; dirt roads and driveways; unprotected streambanks and
pet waste; grass clippings and leaves left on streets and sidewalks;
leaves burned in ditches; atmospheric deposition
and wildlife waste; garbage
and truck exhaust; leaks and spills of oil and gas; used oil
dumping; burning leaves and garbage
overapplied or applied before a rainstorm; spills and leaks
and trucks (brake and tire wear, exhaust); galvanized metal
gutters and downsprouts; industrial activities
What should not enter a storm drain?
•Oil, anti-freeze, paint, cleaning fluids
•Wash water from a commercial car wash
•Wash waters from commercial/industrial activities
•Contaminated foundation drains
•Sanitary sewer discharges
•Septic tank discharges
•Washing machine discharges
•Chlorinated backwash and draining associated with swimming pools
What may enter a storm drain?
•Diverted stream flows
•Flows from riparian habitats and wetlands
•Uncontaminated rising ground water
•Uncontaminated ground water
•Water from crawl space pumps
•Dechlorinated backwash and draining associated with swimming pools
•Fire fighting emergency activities
•Single residential car washing
What can I do to reduce pollution in storm water runoff?
Everybody can reduce pollution in stormwater by implementing a few good "housekeeping" practices.
•Maintain your automobile.
•Regular car maintenance can reduce oil drippings and other pollutants on the road.
•Use biodegradable products for landscaping, car washing, etc.
•Keep storm drains and street gutters clear of debris.
•Bag or mulch lawn clippings so they won't wash into nearby storm drains.
•Clean up after your pets.
•Store and dispose of household chemicals properly. Always use them in the way they were intended. Seal the product to prevent leakage. Take unwanted hazardous wastes to a proper disposal facility.
•Don't treat roofs or driveways with toxic chemicals used for cleaning or moss retardation.
•Plant native vegetation
•Reduce your use of fertilizers, herbicides and pesticides in your yard and garden. If you do apply fertilizer and chemicals to your lawn, follow the application instructions found on the label.
What are Best Management Practices (BMPs)?
Best Management Practices (BMPs) are activities, practices, maintenance procedures, and other management practices designed to prevent or reduce the pollution of waters of the United States. BMPs also include treatment technologies, operating procedures, and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw sewage. BMPs may include structural devices or nonstructural practices.
Glossary of Common Stormwater Terms
Earth refilling a trench or an excavation
An earthen mound used to direct flow of runoff around or through a structure.
Best Management Practices (BMPs)
Good housekeeping solutions that include the proper handling, storage, and disposal of toxic materials to prevent stormwater pollution.
Buffer strip or zone
Strip of erosion-resistant vegetation between a waterway and an area of more intensive land use.
Curbside opening that collects rainwater from streets and serves as an entry point to the storm drain system.
Clean Water Act (CWA) (33 U.S.C. 1251 et seq.)
Requirements of the NPDES program are defined under Sections 307, 402, 318 and 405 of the CWA.
Any pipe for collecting and directing storm water.
Any channel or pipe for collecting directing storm water.
Construction General Permit
A National Pollutant Discharge Elimination System (NPDES) permit issued by the State Water Resources Control Board for the discharge of storm water associated with construction activity from soil disturbance o five (5) acres or more.
A covered channel or a large-diameter pipe that directs water flow below ground level.
Land stripped of vegetation or land that has had its vegetation worn down due to the impacts from the elements or humans.
The release of storm water or other substance from a conveyance system or storage container
The wearing away of land surface by wind or water. Erosion occurs naturally from weather or runoff but can be intensified by land-clearing practices related to farming, residential or industrial development, road building, or timber-cutting.
The process of removing earth, stone, or other materials, usually by digging.
Textile of relatively small mesh or pore size that is used to (a) allow water to pass through while keeping sediment out (permeable), or (b) prevent both runoff and sediment from passing through (impermeable).
The first big rain after an extended dry period (usually summer) which flushes out the accumulated pollutants in the storm drain system and carries them straight to the ocean.
The cutting and/or filling of the land surface to a desired slope or elevation.
The edge of a street (below the curb) designed to drain water runoff from the streets, driveways, parking lots, etc. into catch basins.
1. Any material that poses a threat to human health and/or environment. Typical hazardous substances are toxic, corrosive, ignitable, explosive, or chemically reactive. 2. Any substance named by EPA to be reported is a designated quantity of the substance is spilled in the waters of the United States or if otherwise emitted into the environment.
Household hazardous waste
Common everyday products that people use in and around their homes - including paint, paint thinner, herbicides, and pesticides - that, due to their chemical nature, can be hazardous if not properly disposed. Illegal discharge Any activity or event which results in a release, leak, flow, escape or the placement of any material other than rain water (including liquids or solids) into the storm drain system.
Any connection to the storm drain system that is not permitted: or any legitimate connection that is used for illegal discharge. Inlet An entrance into a ditch, storm drain, or other waterway.
Material storage areas
On site locations where raw materials, products, final products, by-products, or waste materials are stored.
Non-point source pollution
Pollution that does not come from a single, identifiable source. Includes materials that wash from roofs, streets, yards, driveways, sidewalks and other land areas. Collectively, this is the largest source of stormwater pollution.
Non-storm water discharge
Any discharge to municipal separate storm sewer that is not composed entirely of storm water. Discharges containing process wastewater, non-contact cooling water, or sanitary wastewater are non-storm water discharges.
Notice of Intent (NOI)
A formal notice to the State Water Resources Control Board (SWRCB) submitted by the owner/developer that a construction project is about to begin. The NOI provides information on the owner, location, type of project, and certifies that the permittee will comply with the conditions of the construction general permit.
Notice of Termination (NOT)
Form to notify authorities when a construction project is complete.
An authorization, license, or equivalent control document issued by EPA or an approved State agency to implement the requirements of the NPDES program.
A thin, glistening layer of oil on water.
Substances containing carbon which may cause pollution problems in receiving waters.
Liquid organic compounds capable of dissolving solids, gases, or liquids.
A flow of water from one drainage system into a larger system, or into a body of water like a lake, bay, or the ocean.
The quality of a soil that enables water or air to move through it. Usually expressed in inches/hour or inches/day.
Pollution from a single identifiable source such as a factory or a sewage-treatment plant. Most of this pollution is highly regulated at the state and local levels.
Generally, any substance introduced into the environment that adversely affects the usefulness of a resource.
Any form of rain or snow.
The storage of storm water to prevent it from leaving the development site; may be temporary or permanent
Off-site flows which flows onto your site.
Water originating from rainfall and other sources (e.g., sprinkler irrigation) that is found in drainage facilities, rivers, streams, springs, seeps, ponds, lakes, wetlands, and shallow groundwater.
The erosive and digging action in watercourse by flowing water.
Structures, usually dikes or berms, surrounding tanks or other storage containers and designed to catch spilled material from the storage containers.
The process of depositing soil particles, clays, sands, or other sediments that were picked up by runoff.
Soil, sand, and minerals washed from land into water usually after rain, that pile up in reservoirs, rivers, and harbors, destroying fish-nesting areas and clouding the water so that needed sunlight might not reach aquatic plants. Careless farming, mining, and building activities will expose sediment materials, allowing them to be washed off the land after rainfalls.
Include, but not limited to, raw materials; fuels; materials such as solvents, detergents, and plastic pellets; finished materials such as metallic products; raw materials used in food processing or production; hazardous substances designed under Section 101(4) of CERLCA; any chemical the facility is required to report pursuant to Section 313 of Title III or SARA; fertilizers; pesticides; and waste products such as ashes, slag and sludge that have the potential to be released with storm water discharges.
The volume, concentrations, or mass of a pollutant in storm water discharge that can cause or threaten to cause pollution, contamination, or nuisance, that adversely impact human health or the environment, and cause or contribute to a violation of any applicable water quality standards for the receiving water.
Action to prevent pollution where it originates.
Source control BMPs
Everyday operational practices that prevent pollution by reducing potential pollutants at the source.
A device used to prevent spills of liquid materials from storage containers.
Storm drain system
A vast network of pipes and open channels designed for flood control, which discharges straight to the ocean.
Rainwater that enters the storm drain system and empties into lakes, rivers, streams or the ocean.
Water from rain, irrigation, garden hoses or other activities that picks up pollutants (cigarette butts, trash, automotive fluids, used oil, paint, fertilizers and pesticides, lawn and garden clippings and pet waste) from streets, parking lots, driveways and yards and carries them through the storm drain system and straight to the ocean.
An area of land that drains water or runoff to a single point. For example, the watershed of the Ventura River would be the surrounding neighborhoods and natural terrain.