New Mexico
Environment Department

Contact Information:
(505) 827-2855 MAIN // 1-800-219-6157 (toll free)
Environmental Emergencies:
505-827-9329 (24 hrs)

Surface Water Quality

2020 Triennial Review

Executive Summary: In accordance with Section 303(c)(1) of the CWA and New Mexico Administrative Code (“NMAC”), states are required to hold public hearings at least once every three years to review, amend, and adopt water quality standards, as applicable. This is referred to as a “Triennial Review”. Pursuant to Section 74-6-4(F) of the State’s Water Quality Act (“WQA”), the Water Quality Control Commission (“WQCC”) delegated the New Mexico Environment Department (“NMED”) the responsibility for organizing and proposing amendments to the State’s surface water quality standards, codified under 20.6.4 NMAC. This matter has been docketed under WQCC 20-51(R).

NMED is proposing several amendments as part of the Triennial Review which include, but are not limited to the following:

  • Updating definitions ( NMAC)
  • Clarification of language under Review of Standards ( NMAC)
  • Clarification of language under Use Attainability Analysis ( NMAC)
  • Several designated use amendments
    • Existing Use Analysis for non-perennial waters within Los Alamos National Laboratory currently classified under NMAC
    • Existing Use Analysis for perennial classified waters with a secondary contact recreational use
  • Updates to the numeric aquatic life and human health criteria ( NMAC)
  • Updates to the numeric ammonia criteria ( NMAC)


Document Author Date
Public Involvement Plan SWQB 08.11.2020
Notice of Public Comment Period on NMED’s Proposed Amendments English and Spanish (Español) SWQB 11.02.2020
Notice of Public Meeting English and Spanish (Español) SWQB 11.02.2020
Public Comment Draft of NMED’s Proposed Amendments to 20.6.4 NMAC SWQB 11.02.2020
Extension of Public Comment Period NMED’s Proposed Amendments English and Spanish (Español) SWQB 11.25.2020
Public Comments regarding proposed amendments to 20.6.4 NMAC, as submitted to NMED
Petition and Hearing Request SWQB 08.19.2020
Order for Hearing and Appointment of Hearing Officer WQCC 10.19.2020
Scheduling Order
Procedural Order
Hearing Notice in NM Register
WQCC 20-51(R) Pleadings Log Various Various
Final Order and Statement of Reasons
Integrated Rule 20.6.4 NMAC
Submittal Letter to EPA
EPA’s Response and Technical Support Document (TSD)