Regulations
Douglas County SWPPP Checklist: Concrete Washout & GESC Compliance
Douglas County
Jurisdiction: Douglas County (including Castle Rock and overlapping MS4 areas like Lone
Permit / authority: Governing Authority: Douglas County Public Works Engineering / Grading, Erosion, and
Tree) Sediment Control (GESC) Program Douglas County operates under strict Grading, Erosion, and Sediment Control (GESC) permitting. Municipalities within the county, such as Lone Tree, formally adopt the Douglas County GESC Manual into their municipal codes (e.g., Section 15-1-30) to regulate construction runoff.
1. The GESC "Locked Location" Mandate
The Rule: The cleaning of concrete delivery truck chutes is restricted exclusively to the approved concrete washout locations designated on the job site. The Douglas County Nuance: The placement of BMPs must precisely match the Douglas County accepted GESC Plan. If you need to move the washout area due to site phasing, any variation in the location, material, or type of BMP requires prior approval from an Accountable Representative of Douglas County Public Works Engineering. Unilaterally relocating washout containment without this authorization violates the accepted plan.
2. The "No Rebar Support" Prohibition
The Rule: Erosion and sediment control BMPs must be installed per the accepted GESC Plan and GESC Manual. The Douglas County Nuance: Douglas County General Notes explicitly prohibit the use of rebar, steel stakes, or steel fence posts for staking or supporting any erosion or sediment control BMP (with the sole exception of steel tee-posts for construction fencing). If a site builds a temporary washout pit or lined structure, securing the 10-mil liner or perimeter bales with scrap rebar is a direct violation of the GESC notes.
3. Strict Dewatering Coordination
The Rule: The discharge of water containing waste concrete to the storm sewer system is prohibited, and all concrete waste must be properly cleaned up and disposed of at an appropriate location. The Douglas County Nuance: In the event that a washout area accumulates excess stormwater requiring dewatering, all on-site dewatering must be explicitly coordinated with a Douglas County Erosion Control Inspector and be free of sediment in accordance with the GESC Manual. Site Supers cannot independently pump out a flooded concrete washout area.
4. Preconstruction Inspections & Reinspection Penalties
The Rule: Initial-stage erosion and sediment control BMPs must be installed and inspected before major construction activities begin. The Douglas County Nuance: The GESC Manager, General Contractor, and Grading Subcontractor must attend a scheduled preconstruction meeting with the Douglas County Engineering Permits staff. If the physical GESC Field Manual is not maintained on-site, or if the initial washout/BMP installations are not approved by the Douglas County Erosion Control Inspector during this meeting, the county halts progress and charges a mandatory Reinspection Fee before work can proceed.
