United States Government Publishing Office publisher pbl distributor dst United States Government Accountability Office author aut Government Organization text government publication eng GAOREPORTS Legislative Agency Publications gao legislative 2010-08-12 U.S. Government Printing Office 2002-01-11 monographic deposited born digital 44 p. GA 1.13:GAO-02-186 https://www.govinfo.gov/app/details/GAOREPORTS-GAO-02-186 P0b002ee1803882cd f:d02186 DGPO 2010-08-12 2011-03-24 GAOREPORTS-GAO-02-186 machine generated eng fdlp REPORT GAOREPORTS-GAO-02-186 GAO-02-186 Data integrity Information resources management Quality assurance Water quality Web sites EPA National Water Quality Inventory EPA TMDL Tracking System EPA Total Maximum Daily Loads Program EPA Watershed Assessment Tracking and Environmental Results System Other Written Product A02657 The Environmental Protection Agency (EPA) believes that more than 20,000 bodies of water throughout the country are too polluted to meet water quality standards. States use different approaches to identify impaired waters. This variation has led not only to inconsistencies in the listing of impaired waters but also to difficulties in identifying the total number of impaired waters nationwide and the total number of total maximum daily loads (TMDL) needed to bring such waters up to standards. Under the Clean Water Act and its regulations, EPA has given the states some flexibility to develop listing approaches that are tailored to their circumstances. However, some of the approaches have no appropriate scientific basis. States apply a range of quality assurance procedures to ensure the quality of data used to make impairment decisions. Although states have long used quality assurance procedures for the data they collect directly, they have become increasingly vigilant about applying such procedures to data from other sources. Because of inconsistencies in states' approaches to identifying impaired waters, the information in EPA's database of impaired waters is of questionable reliability. The number of impaired waters cannot be compared from one state to the next, and EPA cannot reliably tally the number of TMDLs that must be completed nationwide. EPA's database also distorts the size of some of the states' impaired waters when they are mapped on EPA's website. https://www.govinfo.gov/content/pkg/GAOREPORTS-GAO-02-186/html/GAOREPORTS-GAO-02-186.htm https://www.govinfo.gov/content/pkg/GAOREPORTS-GAO-02-186/pdf/GAOREPORTS-GAO-02-186.pdf GAO-02-186 https://www.govinfo.gov/app/details/GAOREPORTS-GAO-02-186 Other Written Product GAO-02-186; Water Quality: Inconsistent State Approaches Complicate Nation's Efforts to Identify Its Most Polluted Waters; Data integrity Information resources management Quality assurance Water quality Web sites EPA National Water Quality Inventory EPA TMDL Tracking System EPA Total Maximum Daily Loads Program EPA Watershed Assessment Tracking and Environmental Results System Title 40 Part 130.7 40 CFR Part 130.7