Authority to Administer Standards Program

This tribe was granted treatment in a manner similar to a state (TAS) on January 20, 2006.  The tribe was also granted TAS on May 23, 2019, based on a supplemental TAS application, for additional lands.

• [See Decision Document for EPA’s Approval of the Navajo Nation’s Supplemental Application for Treatment in a Similar Manner as a State ]

Tribe Standards in Effect for CWA Purposes

The tribe’s initial water quality standards were approved on April 11, 2006. The standards include designated uses, antidegradation, and other policies and procedures establishing water quality standards for waters of the tribe.

• [See Navajo Nation Water Quality Standards ]
  (Effective March 26, 2009)

Federally Proposed or Promulgated Standards

At this time, there are no federally proposed or promulgated standards applicable to this tribe.

• Navajo Nation Water Quality Standards (PDF)(43 pp, 274 K)
• Decision Document for EPA’s Approval of the Navajo Nation’s Supplemental Application for Treatment in a Similar Manner as a State (PDF)(12 pp, 522 K)