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Impaired Waters and TMDLs

What’s New in Impaired Waters and TMDLs

Final Rule –Treatment of Indian Tribes in a Similar Manner as States for Purposes of Section 303(d) of the Clean Water Act

The EPA has issued a final rule to establish a regulatory process for eligible tribes to apply to the EPA for authority to obtain TAS for the CWA Section 303(d) Impaired Water Listing and TMDL Program. The rule, “Treatment of Indian Tribes in a Similar Manner as States for Purposes of Section 303(d) of the Clean Water Act,” enables eligible tribes to obtain authority to identify impaired waters on their reservations and to establish TMDLs, which serve as plans for attaining and maintaining applicable water quality standards. The final rule was published September 26, 2016. The rule and supporting documents, including EPA’s response to public comments, are also available on using Docket ID No. EPA-HQ-OW-2014-0622.

August 2015: "Information Concerning 2016 Clean Water Act Sections 303(d), 305(b) and 314 Integrated Reporting and Listing Decisions" 

  • EPA released information to assist states in preparing and reviewing their 2016 Integrated Reports, in accordance with Clean Water Action (CWA) Sections 303(d), 305(b) and 314. The memorandum focuses on the following topics:
    • implementing the CWA 303(d) Program Vision;
    • identifying nutrient-impaired waters based on narrative nutrient water quality criteria and direct evidence of failure to support designated uses;
    • implementing the Water Quality Framework, including the Assessment and TMDL Tracking and Implementation ATTAINS redesign and reporting of statewide statistical survey data;
    • providing information about the update to the data in the variable portion of the Fiscal Year 2017 Clean Water Act Section 106 grant allocation formula and
    • clarifying how to assess and assign waters impaired by “pollution” not caused by a “pollutant” to Category 4C