Water Quality: Key EPA and State Decisions Limited by Inconsistent and Incomplete Data

One of the states’ key responsibilities under the Clean Water Act is to
collect data to monitor the condition of the nation’s waters. The act further
requires states to submit reports on the condition of their waters to the U.S.
Environmental Protection Agency (EPA), which then compiles the states’
submissions into a report called the National Water Quality Inventory.
These data, and EPA’s report, have become increasingly important as
national attention has focused on the most effective and efficient way to
target the nation’s water pollution problems and, in particular, on the
soundness of the regulatory decisions that will be required to deal with the
nation’s most heavily polluted waters.

Concerned about the adequacy of the data to support water quality policy
and key regulatory decisions, the Chairman, Subcommittee on Water
Resources and Environment, House Committee on Transportation and
Infrastructure, asked GAO to examine several issues relating to EPA’s
report on water quality and water quality management. Specifically, GAO
was asked to (1) determine whether the information in EPA’s National
Water Quality Inventory is reliable and representative of water quality
conditions nationwide and (2) determine if available data are sufficient to
allow state officials to make key decisions about activities required by the
Clean Water Act, such as identifying waters that do not meet water quality
standards and developing strategies to address those waters.