Stormwater runoff from construction activities can have a significant impact on water quality. As stormwater flows over a construction site, it picks up pollutants like sediment, construction debris, and chemicals such as gasoline, fertilizer, and paint. Polluted stormwater runoff can harm or kill fish and other wildlife. Sedimentation can destroy aquatic habitat and high volumes of runoff can cause stream bank erosion.
Land disturbance activities that occur during grading and construction remove the natural vegetation and allow the bare dirt to erode, unless erosion and sediment control devices are installed at the site. Eroded sediment that is flushed or allowed to flow into the storm sewer network is the main stormwater pollutant in Jefferson County.
Required Land Disturbance Permits
Most land disturbance activities in unincorporated Jefferson County require a Grading Permit or a Notice of Intent. The first step in determining what your project will require is to read Section 16 Land Disturbance from the Jefferson County Zoning Resolution and the Do I Need a Land Disturbance Permit checklist.
A fee will be required at the time of application. To be in regulatory compliance the application must be received at least 45 calendar days prior to the proposed land disturbance activity for a grading plan review and at least 10 calendar days prior for a Notice of Intent.
If the area of disturbance is greater than one (1) acre you must also obtain a Construction Site Stormwater Permit from the Colorado Department of Public Health and Environment (CDPHE). Detailed permit information can be found on the Colorado State Water Quality Permitting page.
Erosion & Sediment Control
Eroded soil at construction sites can pollute rivers, streams and lakes via stormwater runoff. One way to keep this pollution to a minimum is by implementing erosion and sediment control structural best management practices.
Erosion control devices make physical contact with the soil to prevent it from eroding. Examples are:
- Turf Reinforced Matting (TRM)
- Erosion Control Blankets
- Compost Blankets
- Bonded Fiber Matrix
Sediment control is a method that traps or filters sediment that has eroded and is being carried by runoff. Examples are:
- Sediment Pond
- Silt Fence
- Straw Wattles
Successful stormwater management during construction contains erosion control to prevent soil from being dislodged AND sediment control to limit the amount of sediment transported offsite. (See Tips for Controlling Sediment at Construction Sites (PDF))
Additional design and installation specifications for construction site best management practices can be found in the Jefferson County Grading, Erosion and Sediment Control Standard Notes and Details and Urban Drainage and Flood Control District Criteria Manual. Please refer to Volume 3 for design specifications on construction site best management practices.