Stormwater permits exist to regulate the runoff from various disturbance activities and protect waterways. Both state and local agencies are involved in Stormwater Compliance. Sorting out permits can slow a project down, cost time, and create unnecessary risk if something gets missed. In this blog, we will be specifically discussing the State of Colorado, its various local jurisdictions, and how they overlap.
The State of Colorado Agencies
The Colorado Department of Public Health & Environment (CDPHE) is the primary state agency for all environmental regulations. The CDPHE houses the Water Quality Control Division (WQCD). This department is responsible for maintaining water quality and enforcing state and federal water regulations under the Clean Water Act. The WQCD includes the Colorado Discharge Permit System (CDPS), which regulates discharges of pollutants into state waters and enforces water quality standards. When it comes to construction stormwater permits, the CDPS will ultimately issue the state stormwater permit. This permit sets the standards for Stormwater Management Plans (SWMPs), Best Management Practices (BMPs), and site inspections to minimize erosion and protect Colorado’s waterways during construction.
The Colorado Department of Transportation (CDOT) has its own Water Quality Program. This program has a separate permit and water quality/stormwater program which covers infrastructure and operations. Because CDOT’s operations often span multiple municipalities and watersheds, its permit includes additional, agency-specific Best Management Practices (BMPs), inspection procedures, and reporting requirements. These requirements build upon the standard CDPS permit conditions but are tailored to transportation infrastructure—focusing on erosion control, sediment transport prevention, and the proper management of highway runoff during both construction and maintenance activities.
Lastly, the Colorado Water Conservation Board (CWCB) is more oriented toward water quantity, planning, watershed & flood protection. While it doesn’t issue any stormwater permits, the CWCB’s work often overlaps with stormwater management through floodplain mapping, watershed restoration, and community resilience projects—making it an important part of Colorado’s broader water management network.
Local / Regional Agencies and Programs
Within the State of Colorado, municipalities and counties may have their own Municipal Separate Storm Sewer System (MS4) programs. These programs are public storm drainage systems tied to a city or county that collect stormwater runoff (through pipes, ditches, and other conveyances) and discharge it directly into local streams and rivers. Because of this, they may have more stringent regulations in addition to the CDPS permit requirements. Some examples include:
- City of Greeley has its own Stormwater Quality Unit, local ordinances, and handles the MS4 permit they hold via the state.
- Boulder County holds a MS4 permit and runs a stormwater-quality program including illicit discharge detection and public education.
- Weld County covers unincorporated urbanized areas and holds a federally-mandated MS4 permit issued through CDPHE.
Local agencies can also include special districts/regional stormwater authorities. These entities focus on a limited specialized function and often manage multiple jurisdictions that share a watershed. An example of this is the Southeast Metro Stormwater Authority (SEMSWA). SEMSWA operates via an intergovernmental agreement between Arapahoe County, City of Centennial, Arapahoe County Water and Wastewater Authority, East Cherry Creek Valley Water and Sanitation District, and Inverness Water and Sanitation District. These regional authorities help ensure consistent stormwater management practices across jurisdictional boundaries, improving efficiency and protecting shared waterways.
How They Overlap
When starting a construction project in Colorado, you will need a state stormwater permit if the disturbed area is over an acre. Depending on the jurisdiction and location of the project, you may also need a local permit. Local agencies often implement the requirements of state permits at the ground level and may have additional requirements to meet their specific regulations. It’s important to have all the required permits and be in compliance with both the state and local stormwater agencies.
At Summit, we take the pressure off your team by managing the permitting process from start to finish. We help identify what jurisdiction governs your project, the exact permits your project needs, keep you on track with compliance throughout the entire process (from pre-construction to post-construction), and handle permit closeouts. With Summit as your stormwater compliance contractor you can avoid delays, reduce the risk of violations, and keep your project moving forward. Reach out today to see how we can support your project!