Denver, CO Environmental Rules: Stormwater Management (2026)

Denver requires every developer of land to provide on-site drainage and detention facilities adequate to control stormwater, groundwater, and runoff contributed from neighboring property. Before the city issues a building permit, the owner or applicant must submit a detailed storm drainage plan to the manager of transportation and infrastructure covering drainage courses, channels, conduits, detention ponds, and water-quality facilities, and the permit cannot issue until that plan is approved. Separately, every lot or parcel pays an annual storm drainage service charge based on its impervious surface area, funding operation and maintenance of the citywide storm drainage system: since Denver is a consolidated city and county, the requirement and the charge apply everywhere within its boundaries, not just unincorporated land.