​Construction Site

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 gas, fertilizer, and paint. Polluted stormwater runoff can harm or kill fish and other wildlife. Sedimentation can destroy aquatic habitats, and high runoff can cause stream bank erosion.

Before obtaining a City of Thornton construction permit, the owner/contractor must obtain a Colorado Department of Public Health and Environment (CDPHE) Stormwater Discharges Associated with Construction Activity Permit Application. Under current regulations, this permit application covers construction sites disturbing one or more acres that include construction activities such as clearing, grading, excavation, and other ground disturbance activities.

Please access the Colorado Department of Public Health and Environment Website, where more information can be obtained.