Regulations
San Miguel County SWPPP Checklist: Concrete Washout & Alpine Stormwater
San Miguel County
Jurisdiction: San Miguel County (Telluride, Mountain Village, and unincorporated areas)
Permit / authority: Governing Permits: San Miguel County Land Use Code / CDPHE-WQCD General Permit
areas) Operating in San Miguel County requires navigating some of the tightest logistical spaces in Colorado, bounded heavily by the San Miguel River watershed. The county strictly enforces state-level protections on an extreme local level to protect alpine riparian zones and wetland habitats.
1. The Strict 50-Foot Waterbody Mandate
The Rule: Concrete waste must be placed in a designated temporary concrete washout facility. The San Miguel Nuance: San Miguel County Planning Commission explicitly dictates that any concrete washout facility must be located a minimum of 50 feet from state waters. Because Telluride and the surrounding canyon plots run directly parallel to the San Miguel River and its tributaries, finding a compliant 50-foot buffer on these tight mountain lots is exceptionally difficult. An in-ground pit dug within this setback will fail initial site inspection.
2. The CDOT Right-of-Way (ROW) Prohibition
The Rule: Discharges to the MS4, public roads, or drainage systems are prohibited. The San Miguel Nuance: In steep canyon environments, flat staging space is practically nonexistent, pushing contractors toward the street. However, San Miguel County explicitly mandates that concrete washout "shall NOT be allowed to flow into the drainage ways, inlets, receiving waters, or in the CDOT ROW". Staging a leaky washout setup or a washout pan on the shoulder of Highway 145 (a CDOT ROW) is an immediate violation of both county land use and state highway regulations.
3. Separate CDPS Permits for On-Site Batching
The Rule: Standard construction stormwater permits cover basic earth-disturbance runoff. The San Miguel Nuance: Due to the extreme remoteness of San Miguel sites (often requiring long hauls from Montrose or Ridgway), contractors frequently utilize on-site mobile concrete batch plants. The county explicitly flags this in their land use approvals: concrete batch plants require a separate, distinct CDPS Stormwater Permit through the CDPHE-WQCD (Water Quality Control Division). The washout containment for an on-site batch plant is scrutinized under a much heavier industrial standard than a standard foundation pour.
4. Alpine Revegetation & Development Standards (LUC Article 5)
The Rule: Sites must be permanently stabilized upon completion to prevent long-term erosion. The San Miguel Nuance: High-elevation topsoil takes years to recover from disturbance. Under Article 5 of the San Miguel County Land Use Code, the county enforces strict environmental and visual impact regulations. If a temporary, in-ground washout pit is excavated, the scarred earth must be fully restored to its native state. The county routinely requires the contractor to post a financial security (letter of credit or bond) to cover the estimated revegetation costs. Digging a temporary pit directly threatens this bond, as the vegetation must successfully re-establish before the county releases the financial hold.
