The State of New Mexico is taking a major step toward expanding state oversight of surface water discharges and impacts through proposed amendments to 20.6.2 NMAC and adoption of a new 20.6.5 NMAC rule. Together, these proposals would establish a new state surface water permitting program and create the regulatory framework necessary for New Mexico to assume administration of the federal NPDES program from EPA. These proposals stem from legislation enacted during the 2025 New Mexico Legislative Session and would give the New Mexico Environment Department (NMED) authority to implement significant new surface water permitting programs across the state.
If adopted, the proposed rules could affect a wide range of industries, including municipal wastewater systems, mining operations, industrial facilities, utilities, construction projects, aggregate operations, and energy development. While much of the attention has focused on New Mexico’s effort to assume administration of the federal National Pollutant Discharge Elimination System (NPDES) program, the rulemaking goes beyond NPDES delegation and proposes a new state permitting framework for certain discharges and dredge-and-fill activities affecting New Mexico surface waters.
NMED petitioned the Water Quality Control Commission (WQCC), New Mexico’s rulemaking body for water quality regulations, to adopt the proposed rules. Following the completion of the June 2026 rulemaking hearing, the proposed regulations remain under Commission deliberation. As a result, now is an appropriate time for regulated facilities to understand the proposed requirements and begin evaluating potential compliance and permitting implications.
Why Is New Mexico Developing These Rules?
The proposed regulations were developed following passage of Senate Bill 21 during the 2025 legislative session. According to NMED, the objective is to create a comprehensive state surface water permitting framework while addressing regulatory gaps related to waters that may not be subject to federal Clean Water Act jurisdiction.
To accomplish this goal, NMED has proposed two complementary regulatory programs:
- Amendments to 6.2 NMAC establishing a state permitting program for certain surface water discharges and dredged or fill activities regulated under the New Mexico Water Quality Act.
- New 6.5 NMAC, which would establish New Mexico’s Pollutant Discharge Elimination System (NMPDES) program and provide the regulatory framework necessary for New Mexico to obtain and maintain EPA authorization to administer the NPDES program within the state.
Although these programs are related, they serve different purposes and could affect facilities in different ways.
Proposed Changes to 20.6.2 NMAC
The proposed amendments to 20.6.2 NMAC would create a new state surface water permitting program that includes requirements for surface water discharges, individual permits, general permits, dredged-and-fill activities, permit modifications, public participation, mitigation, and permitting fees.
New Permitting Requirements for Waters of the State
One of the primary drivers behind the proposed rulemaking is the distinction between federally regulated “waters of the United States” (WOTUS) and the broader category of “surface waters of the state.” While federal Clean Water Act permitting programs apply only to waters meeting the federal WOTUS definition, New Mexico’s proposed 20.6.2 NMAC amendments would establish permitting requirements for certain discharges and dredge-and-fill activities affecting state waters that may not be federally jurisdictional. As a result, some activities that may not currently require federal permitting could become subject to state permitting requirements.
New Surface Water Discharge Permitting Framework
One of the most significant elements of the proposal involves activities that discharge dredged or fill material into surface waters of the state. While the rule includes numerous exemptions and is intended to avoid duplicative permitting where federal permits already exist, it creates a state-level regulatory program that did not previously exist in this form.
Dredge-and-Fill Activities
One of the most significant elements of the proposal involves dredged and fill materials into surface waters of the state. Under the proposed rule, applicants may be required to demonstrate:
- Avoidance of impacts to aquatic resources where practicable.
- Minimization of unavoidable impacts.
- Use of best management practices.
- Compensatory mitigation for certain unavoidable impacts to aquatic resources
These provisions mirror many concepts familiar to facilities that have previously navigated federal Clean Water Act Section 404 permitting requirements.
Expanded Public Participation Requirements
The proposed amendments would also establish extensive public notice and participation requirements. Depending on the project, applicants may be required to notify nearby landowners and provide site postings. NMED would be responsible for distributing notices to agencies, tribes, pueblos, land grant organizations, ditch associations, and interested stakeholders.
For facilities pursuing projects that may require authorization under the proposed state surface water permitting program, these requirements could influence project schedules, stakeholder engagement efforts, and permitting timelines.
What Is the New 20.6.5 NMAC Rule?
While 20.6.2 NMAC focuses on a state surface water permitting program, proposed 20.6.5 NMAC establishes the framework for New Mexico’s future New Mexico Pollutant Discharge Elimination System (NMPDES) program.
The rule is designed to closely align with federal NPDES requirements and incorporates numerous federal regulations by reference. NMED developed the program to satisfy the requirements necessary for EPA authorization under the Clean Water Act.
Under the proposed framework, NMED would ultimately be responsible for:
- Issuing discharge permits.
- Renewing permits.
- Processing permit modifications.
- Approving general permit coverage.
- Conducting compliance and enforcement activities.
- Administering public participation procedures.
Importantly, the permit requirement would not become effective until EPA delegation and transition agreements are in place. This means facilities with existing EPA-issued permits are not expected to immediately transition to NMED administration upon adoption of the state rules alone. However, the proposal clearly signals New Mexico’s intent to assume a larger role in surface water permitting.
New Fees May Affect Future Permit Holders
Both rule packages include proposed fee structures intended to support implementation of the state’s permitting programs. Proposed fees include permit application fees, annual permit fees, permit modification fees, antidegradation review fees, mitigation review fees, and general permit fees.
The proposal would establish state permit application and annual fees for activities regulated under the new programs. Given that fee structures and implementation details remain under review, facilities are recommended to continue to monitor future developments as the rulemaking progresses.
Potential Impacts on Regulated Facilities
Although the final rules remain under consideration, facilities should begin evaluating how the proposed programs may affect future operations and permitting strategies.
Industries most likely to be affected include:
- Municipal wastewater treatment facilities
- Industrial wastewater dischargers
- Mining operations
- Aggregate and construction materials facilities
- Construction and development projects
- Electric utilities
- Manufacturing facilities
- Oil and gas facilities subject to stormwater permitting requirements
Potential impacts may include:
- Greater interaction with NMED during future permitting actions.
- Reevaluating activities into previously exempt waterways to determine if they will require a permit under the new State system.
- Revising operations currently permitted under a Federal NPDES system, once operators are required to transition to a state permit.
- Expanded public participation and stakeholder engagement requirements.
- New permitting fees and administrative procedures.
- Changes to permit application and renewal processes over time.
Current Status of the Rulemaking
NMED released draft rules for public review in August 2025 and subsequently petitioned the WQCC to adopt the regulations. The WQCC conducted a rulemaking hearing from June 8 through June 18, 2026. At the time of publication, the Commission has not issued a final decision, and the proposed rules remain under deliberation.
As a result, the final regulatory requirements, implementation timelines, and permit transition processes could change before adoption.
What Should Facilities Do Now?
Even though the rules are not yet final, facilities should consider taking the following steps:
- Monitor ongoing developments in the WQCC rulemaking process.
- Identify existing NPDES permits that may require future renewals.
- Evaluate upcoming projects that could affect streams, wetlands, or other aquatic resources.
- Assess potential permitting timelines and budget impacts associated with the proposed fees.
- Develop a strategy for future interactions with NMED, should New Mexico ultimately assume NPDES authority.
Early evaluation can help facilities avoid project delays and better prepare for future compliance obligations if the proposed programs are adopted.
How Trinity Can Help
Trinity Consultants is actively tracking New Mexico’s evolving surface water permitting landscape. Our team can assist facilities with applicability evaluations, permitting strategy, regulatory impact assessments, project planning, public participation planning, NPDES compliance support, and interpretation of final rule requirements as they become available.
For assistance evaluating how the proposed amendments to 20.6.2 NMAC and proposed 20.6.5 NMAC may affect your facility, please contact Trinity’s Albuquerque Office at 505.266.6611.
