&EPA United States Environmental Protection Agency Office of Water (45G3F)' Washington, DC 20460 EPA841-F-95-G1G December 1995 Water Quality Conditions in the United States A Profile from the 1994 National Water Quality Inventory Report to Congress Findings Based on the latest information reported to EPA by States, Tribes, and other jurisdictions with water quality responsibili- ties, about 40% of the Nation's surveyed rivers, lakes, and estuaries are not clean enough for basic uses such as fishing or swimming. The results are consistent with data last reported in 1992 and show that rnore work is needed if waters are to be made clean and healthy in all communities.; These results are based on water quality surveys conducted in 1992 and 1993. Nationwide, 1 7% of rivers, 42% of lakes, and 78% of estuaries were surveyed. Polluted runoff from rainstorms and snowmelt is the leading cause of impairment in rivers, lakes, and estuaries. For rivers and lakes, runoff from agricultural lands is the biggest source of pollution. Storm sewers and urban runoff are the leading sources of pollution in estuaries. Bacteria, which can cause illnesses in swimmers and others involved in water-contact sports, are the rnost common pollutants impacting rivers. Nutrients, such as phosphates and nitrates, are the most often reported pollutant in Jakes and estuaries. In excess, nutrients can create a chain of impacts that include algal blooms, fish kills, foul odors, and weed growth. I = Background Water quality surveys are conducted to determine a " waterbody's overall health, including whether or not basic uses are being met. States, Tribes, or other jurisdictions define appropriate uses for a waterbody and incorporate these uses into water quaNty standards that are approved by EPA. States and other jurisdictions conductwater quality surveys and report the findings to EPA every 2 years. EPA then prepares a biennial Report to Congress, which represents the most complete and up-to-date snapshot of water quality conditions around the country. This report is the tenth in a series of reports that have been prepared and submitted to Congress since 1975. . About 40% of the Nation's surveyed rivers, lakes, and estuaries are not clean enough to meet basic uses such as fishing or swimming. How Our Waters Are Used Aquatic Life Fish Consumption Shellfishing Swimming Other Recreational Uses Drinking Water ssgair -Agriculture ------- Leading Causes ! of Pollution i 1 2 3 4 5 ; Bacteria Siltation ', Nutrients ! Oxygen-Depleting Substances Metals About 36% of surveyed rivers are impaired - about the equivalent of 100 Mississippi Rivers. The U.S. has 3.5 million miles of rivers and streams. Surveys were conducted on 615,806 miles, or 17%. Leading Sources ' of Pollution 1 2 3 4 5 Agriculture Municipal Sewage Treatment Plants Hydrologic/Habitat Modification Urban Runoff/ Storm Sewers Resource Extraction Leading Causes of Pollution 1 2 3 4 5 Nutrients Siltation Oxygen-Depleting Substances Metals Suspended Solids About 37% of surveyed lakes are impaired - about the equivalent of 6 Great Salt Lakes. The U.S. has 41 million acres of lakes. Surveys were conducted on about 17 million acres, or 42%.* *Excludes the Great Lakes. Leading Sources of Pollution 1 2 3 ' 4 5 Agriculture Municipal Sewage Treatment Plants Urban Runoff/ ' Storm Sewers Unspecified Nonpoint Sources Hydrologic/Habitat Modification Leading Causes of Pollution Nutrients Bacteria Oxygen-Depleting Substances Habitat Alterations Oil and Grease M Estuary Profile • About 37% of surveyed estuaries are impaired - about the equiva- lent of 3 Chesapeake Bays. • The U.S. has 34,400 square miles of estuaries.* • Surveys were conducted on about 27,000 square miles, or 78%. *Excludes an unknown number of estuaries in Alaska. Leading'Sources of Pollution 1 2 3 4 5 Urban Runoff/ Storm Sewers Municipal Sewage Treatment Plants Agriculture Industrial Point Sources Petroleum Activities ------- |