Regulations
Weld County SWPPP Checklist: Concrete Washout & Construction Compliance
Weld County
Jurisdiction: Weld County MS4 Area (including unincorporated areas near Greeley, Windsor,
Permit / authority: Governing Permits: Weld County Grading Permit / CDPS General Permit
Firestone, and Erie) Weld County operates a strict Construction Sites Program coordinated between its Planning and Public Works departments to meet Colorado Discharge Permit System (CDPS) requirements. The county enforces highly specific thresholds for material management and BMP modifications.
1. The "Concrete Slobber" & Ground Wash Prohibition
The Rule: A designated washout structure must be provided during all concrete, stucco, and masonry work. Tools and chutes must not be washed off onto stockpiles or the ground. The Weld County Nuance: Weld County's official stormwater guidelines explicitly declare that "concrete 'slobber' is considered waste and must be removed". Inspectors will actively cite sites that allow incidental concrete spillage or "slobber" to accumulate outside of the approved Material Management (MM-1) Concrete Washout Area.
2. The Strict 2/3rds Capacity Mandate
The Rule: Washouts must be placed away from drainage areas or waterways and actively maintained to prevent illicit discharges. The Weld County Nuance: While the state permit allows for some interpretation of "adequate freeboard," Weld County explicitly mandates that washouts must be emptied at 2/3rds capacity. Allowing a washout pit or pan to exceed this threshold is a direct violation of the county's Construction Sites Program.
3. The 45-Day Routine & 14-Day Compliance Cycle
The Rule: The site's Qualified Stormwater Manager (QSM) must inspect temporary control measures at least every two weeks and after storm runoff events. The Weld County Nuance: Weld County Public Works independently conducts routine inspections of construction sites within the MS4 area at least every 45 days. If a washout violation is discovered during this routine check, the county triggers a mandatory Compliance Inspection within 14 days. These compliance inspections are subject to formal re-inspection fees.
4. BMP Modification & As-Built Re-inspection Fees
The Rule: Site conditions must reflect the county-approved Sediment and Erosion Control Plan. The Weld County Nuance: If washout locations or other BMPs need to be changed due to site phasing, Public Works must be contacted to determine if a formal Grading Permit modification is required. At the end of the project, the county verifies that the certified as-built drawings match the actual site conditions and any modifications made during construction. If they do not match, the site operator is charged a $50/hour re-inspection fee for follow-up verification.
