EPA must approve the WQS adopted by states, authorized tribes, and territories. If EPA ultimately decides that it cannot reach agreement with a state, tribe, or territory, the Agency can promulgate substitute WQS by going through the formal federal rulemaking process.

Opportunities for public comment on proposed WQS are provided at a minimum of two steps in the approval process.

The responsibility for establishing WQS has always been vested in the states and territories, however EPA must assign WQS authority to tribes. Tribes must meet certain tests before they can assume WQS programs. Before the tribes are given such authorization, EPA must set WQS on Indian lands.

For more information on water quality standards, please visit EPA-Office of Science and Technology's Water Quality Criteria and Standards Program web site.