EPA Regulation of Stormwater in Santa Fe County
Programs in place
These programs regulate the stormwater discharges of Santa Fe County as part of Phase II regulations issued in 1999. These regulations require that small Municipal Separate Storm Sewer Systems (MS4s) apply for permits.
New Mexico is one of three states that do not have authorization to issue permits under the Clean Water Act, including Massachusetts and New Hampshire. This means that the Federal agency, EPA, issues permits directly to local governments (cities and counties) and to New Mexico businesses and construction sites.
While new stormwater regulations have not yet been formally proposed or codified, EPA has incorporated many new features into the General Permit for New Mexico. This Watershed General Permit was proposed on Feb. 12, 2013.
The proposed permit can be found on the Federal Register :: New Mexico Statewide Municipal Separate Storm Sewer System (MS4) General Permit Proposal.
NMED State Permitting Program
NMED is pursuing delegation of the federal permitting program from the EPA under the authority of the New Mexico Pollutant Discharge Elimination System (NMPDES) Act. The NMED Surface Water Quality Bureau (SWQB) is also developing the State Permitting Program under the authority of the New Mexico Water Quality Act to regulate both point source and dredge and fill discharges into Surface Waters of the State (SWOTS).
Additional information and updates on the development of the program can be found on the NMED Surface Water Quality webpage.
Additional materials prepared by the NMED are below:
Santa Fe County's Stormwater Program
Santa Fe County's stormwater program is driven by the goals identified in the Stormwater Management Program. This program is a requirement of the MS4 permit, but is applied county-wide in an effort to incorporate the best practices beyond the Santa Fe urban area.
Map Pending
As the operator of a small MS4, Santa Fe County must develop, implement, and enforce a SWMP to reduce the discharge of pollutants from all sources to the “maximum extent practicable” (MEP) to protect water quality and to satisfy applicable surface water quality standards using Best Management Practices (BMPs).
The Santa Fe County SWMP includes measurable strategies and goals for each of the six minimum control measures within the current NMR040000 NPDES Small MS4 Permit for New Mexico, May 2007. This permit expired June 30, 2012, and has been in administrative continuance since. EPA issued a draft proposed NPDES Small MS4 Permit for New Mexico in July 2015, started discussing a Statewide MS4 Permit with New Mexico permittees in March 2024, and issued a proposed state-wide permit in 2026. No permit changes have been implemented since 2007.
Supporting Documentation
EPA Annual Reports (in Compliance with MS4 Permit NMR040000)
Supporting Reports & Figures
Figures
- Santa Fe Urban Area Map
- MS4 Priority Areas Map (supplemental to urban area map)
- Santa Fe River Impairments & TMDL Information Map
- County Outfalls and Conveyances Map
- MS4 Dry Weather Field Screen Locations
- Proposed Wet Weather Monitoring Locations
- Santa Fe County Pollutant Sources and Priority Areas
Reports
- Santa Fe County Stormwater Monitoring Program Recommendations (6.24..2026)
- Field Samlping Plan for Stormwater Quality Monitoring (supplemental to Monitoring Program recommendations)
- Quality Assurance Project Plan for Stormwater Quality Monitoring (supplemental to Monitoring Program recommendations)
- Recommendations or Alterations to Santa Fe County Codes Related to Stormwater Management (2.21.2026)
- Stormwater Program Summary and Recomendations for Compliance with the MS4 permit (5.9.2025)
- MS4 Outfall Screening Report (2.12.2025)
- County Code Review and Recommendations Related to MS4 Permit Requirements (7.7.2023)
Administrative Comments
On March 4, 2026 the EPA published a proposed state-wide New Mexico Municipal Seterate Storm Sewer System (MS4) General Permit. This permit, if codified, would replace the existing NPDES Permit NMR04000. The porposed permit can be found on the Federal Register :: New Mexico Statewide Municipal Separate Storm Sewer System (MS4) General Permit Proposal.
Santa Fe County Comments on proposed NPDES Permit No. NMR04B000
On March 6, 2024, the EPA Region 6 NPDES Permitting and Wetlands Section shared a New Mexico Strawman MS4 Permit with operators across New Mexico. This document served as a working space to develop an updated draft permit to replaced the 2007 permit.
Santa Fe County Comments on the 2024 EPA MS4 Strawman Permit