Our drinking water supplies, shellfishing waters and bathing beaches are fouled by uncontrolled pollution when rainwater and snowmelt wash over city streets, parking lots, and suburban lawns and pick up toxic chemicals, disease-causing organisms, and dirt and trash. This problem is called urban stormwater pollution. Recent studies have found that urban stormwater rivals and in some cases exceeds sewage plants and large factories as a source of damaging pollutants.

Two hundred years of unregulated, unmanaged urban stormwater have contributed to many severe public health problems and expensive natural resource losses in the United States. Left unregulated and uncontrolled, urban stormwater:

• pollutes drinking water sources, filling in reservoirs with clogging silt and oxygen-robbing nutrients and contributing to drinking water emergencies;
  
  
• fills in navigable waterways with contaminated sediment, leaving us with increased dredging and spoil disposal costs;
  
  
• closes or shrinks lucrative rockfish, shad, flounder, crab, oyster, and other commercial fisheries due to chemical contamination, oxygen starvation, and the resulting loss of habitat;
  
  
• fouls beaches and other recreational waters, causing losses in revenues from declines in boating, fishing, duck hunting and coastal tourism;
  
  
• scours smaller stream channels and dumps huge gravel and silt loads, ruining fish and amphibian habitat;
  
  
• obliterates small streams, springs and wetlands during development (these natural waterbodies are sources of clean ground and surface water and serve as habitat for aquatic life); and
  
  
• damages homes and businesses during the flash floods common where stormwater is left uncontrolled

Each of these problems carries heavy costs: increased spending on health care, higher insurance and drinking water rates, declining stocks of commercial fish, and loss of coastal tourism revenues. Americans are spending millions on these symptoms of stormwater pollution instead of trying to control the root cause.

For a collection of case studies documenting some of the most effective strategies being employed by communities around the country to control urban runoff pollution, see Stormwater Strategies.

last revised 11.10.00