Epa Offers Nonpoint Source Guidance For Wetlands, Streams
The U.S. Environmental Protection Agency (EPA) has published a technical guidance and reference document for use by state, territory, and authorized tribal managers as well as the public in the implementation of nonpoint source pollution management programs.
The new guidance contains information on the best available, economically achievable means of reducing nonpoint source pollution through the protection and restoration of wetlands and riparian areas, as well as the implementation of vegetated treatment systems.
The most recent national water quality inventory, conducted in 2000, shows that nearly 39 percent of assessed rivers and streams, 45 percent of lakes, reservoirs, and ponds, and 51 percent of estuaries in the United States remain too polluted for fishing, swimming, and other uses.
Habitat alterations, such as hydromodification, dredging, streambank destabilization, and the loss or degradation of wetlands, contribute to the impacts on quality.
Many pollutants are delivered to these surface waters and to ground water from no single point. These nonpoint sources include urban runoff, agricultural runoff, and atmospheric deposition of contaminants.
The leading causes of impairment are nutrients, pathogens, siltation, oxygen-depleting substances, metals, and suspended solids, the EPA says.
Wetlands and streamside areas can protect water quality and reduce adverse water quality impacts associated with nonpoint source pollution, and they help decrease the need for costly storm water and flood protection facilities.
So, the EPA advises in this guidance document, wetlands and riparian areas are an important component of a combination of management practices that can be used to reduce nonpoint source pollution pollution.
In their natural condition wetlands and riparian areas provide habitat for feeding, nesting, cover, and breeding to many species of birds, fishes, amphibians, reptiles, and mammals.
Although wetlands have long been recognized for their water quality improvement functions, unrestricted use of natural wetlands as receptacles for point and nonpoint source pollution, such as urban stormwater and other sources of runoff, could have an adverse effect on wetlands and wetland organisms, the EPA cautions.
The guidance provides a brief introduction to NPS pollution and the national effort to control it. It introduces wetlands, riparian areas, and vegetated treatment systems, explaining what they are, how they function, and what their importance is in terms of nonpoint source pollution.
It defines what management measures are and how they work to prevent nonpoint source pollution, and it describes four management practices for the protection of wetlands and riparian areas.
The document explains what restoration is and discusses three practices to implement the management measure for restoration of wetlands and riparian areas. Finally, it describes the management measure and three practices related to vegetated treatment systems.
Use of the information in the guidance is voluntary, the EPA says, though many states have requirements for protecting wetlands and riparian areas from nonpoint source pollution.
National Management Measures to Protect and Restore Wetlands and Riparian Areas for the Abatement of Nonpoint Source Pollution is online at www.epa.gov/owow/nps/wetmeasures/.
Provided by the Environmental News Service.
