Regulations
La Plata County SWPPP Checklist: Concrete Washout & Stormwater Controls
La Plata County
Jurisdiction: La Plata County (including City of Durango)
Permit / authority: Governing Permits: City of Durango Stormwater Quality Permit / CDPS General Permit
Operating in La Plata County, specifically within the City of Durango limits, requires adherence to strict Animas River watershed protections. City Code Enforcement and the county building division enforce rigorous site staging rules that differ significantly from standard state MS4 baselines.
1. The 1/2 Acre Stormwater Permit Trigger
The Rule: The State of Colorado generally requires a formal stormwater discharge permit for construction activities that disturb one or more acres of land. The Durango Nuance: The City of Durango imposes a much stricter threshold. Under municipal guidelines, a formal Stormwater Quality Permit is required for any disturbance of land in excess of ½ (one-half) acre. If temporary excavation for washout pits, material staging, and mass grading exceeds this half-acre mark, full municipal SWPPP oversight is immediately triggered.
2. Authorized Washout & The "Wind-Tip" Mandate (Sec. 10-10-16)
The Rule: Prevention of concrete and mortar washout materials from accessing stormwater drainage areas is strictly mandated under City Code Sec. 11-71 and 25-176. The Durango Nuance: Durango enforces a strict "authorized pit" requirement alongside heavy wind regulations. Under Chapter 27, Sec. 10-10-16(8)i, only explicitly authorized concrete washout pits or containment shall be utilized. Additionally, this same subsection dictates that any temporary containment (including porta-johns and light site equipment) must be physically anchored to prevent tipping by high mountain winds or vandals. Unanchored containment that spills alkaline water is prosecuted as an accidental discharge violating state water laws.
3. The Revocable Right-of-Way (ROW) $5,000 Bond
The Rule: Equipment and materials should ideally be staged on private property. The Durango Nuance: Due to the tight, historic lot lines in downtown Durango, staging in the street is often unavoidable. However, any work or storage of materials/equipment (such as a steel washout pan) in the City Right-of-Way explicitly requires a Revocable Right-of-Way Permit. Under Sec. 21-69, the applicant must hold a business license, general liability insurance, and post a $5,000 bond or letter of credit with the city prior to placement.
4. Daily Street Maintenance & Tracked Vehicle Ban
The Rule: Vehicle tracking of sediment onto paved roadways must be mitigated. The Durango Nuance: Durango code dictates a hard daily deadline. Any mud, concrete debris, or track-out deposited onto city right-of-ways must be removed and disposed of properly on a daily basis to prevent access to stormwater drainage areas. Furthermore, the city explicitly states that tracked vehicles (such as excavators digging out temporary pits) shall not be operated on paved surfaces without physical street protection (like heavy mats or tires).
