LEARN MORE about storm water management
Know the fundamentals of managing storm water runoff
The EPA Clean Water Act (CWA) of 1972 (amended in 1977 and 1987) includes as a key component regulations for managing storm water runoff to protect the quality of waterways by reducing discharge of sediment, oil and chemicals into storm drains, surface water and groundwater.
Three main categories of required participant
Industrial – 450 Standard Industrial Classification (SIC) codes including manufacturing, mining and service industries
Government – municipalities, counties, states, plus military bases, national parks and other Federal government operations
Construction – residential, commercial, road and highway
Phase II of the regulations (effective March 2003) requires any construction site that disturbs one acre or more of land to have an EPA-issued National Pollutant Discharge Elimination System (NPDES) Construction Storm Water Permit in place before construction can begin. The NPDES permit program controls water pollution by regulating point sources and non-point sources that discharge pollutants into waters of the United States.
Some facts of interest
-
Approximately 70% of all storm drains lead directly, without treatment, to open waterways.
-
Of all impaired rivers and lakes in the United States, 46% are polluted by uncontrolled storm water runoff.
-
Just a single quart of spilled oil can cause a two-acre oil slick on polluted water bodies.
-
If not properly managed, soil erosion from just a one-acre construction site could discharge as much as 20 to 150 tons of sediment in one year into surface waters.
-
Under Section 309 of CWA, for a first offense of criminal negligence, the minimum fine is $2500, with a maximum of $25,000 per day of violation and up to a year in jail. For a second offense there's a maximum fine of $50,000 per day. For a knowing endangerment violation (placing another person in imminent danger of death or serious bodily injury) the fine may be up to $250,000 and/or imprisonment up to 15 years for an individual, or up to $1,000,000 for an organization. In 2001 a major retail chain actually was fined $1 million by the EPA for storm water violations during construction.
Key definitions
NPDES – National Pollutant Discharge Elimination System – The technical name for EPA's storm water management regulations. Regulated entities must comply with NPDES, 40 CFR 122.26 (1999).
SWPPP – Storm Water Pollution Prevention Plan, an erosion, sediment and waste chemical control plan that all regulated entities must file with the EPA to be granted a storm water permit.
BMP – Best Management Practices, including operating procedures and products to control site runoff, spills, leaks and drainage from raw material storage. Any SWPPP requires inclusion of a detailed description of BMP planned for use at the site.
MEP – Maximum Extent Practicable. Storm water permits require the discharge of pollutants into storm drains be reduced to the ''Maximum Extent Practicable.''
Non-point source pollution – Contamination from storm water runoff. Point source pollution can be easily traced to a single source, such as a catastrophic leak from a storage tank. Non-point source pollution, in contrast, has many contributors; for example, oil leaks from vehicles in parking lots, sediment from multiple sources, a chemical or oil sheen from drums, tanks, equipment or raw materials stored outdoors.
WQS – Water Quality Standards. Risk-based requirements that set site-specific allowable pollutant levels for individual water bodies, such as rivers, lakes, streams and wetlands. States set WQS by designating uses for the water body (for example, recreation, water supply, aquatic life, agriculture) and applying water quality criteria to protect the designated uses. An anti-degradation policy is also issued by each state to maintain and protect existing uses and high-quality waters.
TMDL – Total Maximum Daily Load. Water bodies that are repeatedly out of compliance with applicable water quality standards are subjected to a Total Maximum Daily Load – a calculation of the maximum amount of a pollutant that a water body can receive and still meet WQS. The TMDL is determined after study of the specific properties of the water body and the pollutant sources that contribute to the non-compliant status. Once the TMDL assessment is completed and the maximum pollutant loading capacity defined, an implementation plan is developed that outlines the measures needed to reduce pollutant loading to the non-compliant water body and bring it into compliance. Over 60,000 TMDLs are proposed or in development for U.S. waters in the next 15 years. Following issuance of a water quality standard or TMDL for a water body, implementation of the requirements involves modification to NPDES permits for facilities discharging to the water body. While the effluent guidelines have been largely successful because they apply to specific sources and are enforceable the WQS have been much less successful.
As of 2007, approximately half the rivers, lakes and bays under EPA oversight were still not safe enough for fishing and swimming.
Erosion and sediment controls must be designed to retain sediment and process byproducts on-site, adequately fit for your facility's needs, and properly maintained. These controls may effectively include tools such as:
Back