Quick Answer
The City and County of Denver’s Wastewater Engineering Department has final say over any new major development and redevelopment in the county that results in the discharge of stormwater or wastewater. Developments of half an acre or more, projects involving sanitary sewer lines, storm lines, drainage channels, or water quality facilities all require permit review. The process runs through four stages: Construction Activities Stormwater Discharge Permit (CASDP), Sewer Use and Drainage Permit (SUDP), technical design standards compliance, and standard fee payment. A licensed professional engineer must lead the technical submittal at each stage. Engaging a Colorado civil engineering firm with direct Denver Wastewater Engineering Department experience before site planning begins is what keeps the submittal process on a predictable timeline.
Who Needs a Denver Wastewater Engineering Permit
The City and County of Denver’s Wastewater Engineering Department has final say over any new major development and redevelopment in the county. This includes development requiring a permit that results in the discharge of stormwater or wastewater, such as those resulting from the following:
- Sites and development of one-half acre or more
- Sanitary sewer lines
- Storm lines
- Drainage channels
- Water quality facilities
The Wastewater Engineering and Permitting Division provides services to meet Denver’s current and future needs for safe and effective wastewater collection, transport, and treatment. Applications for construction permits are processed as either minor construction or major construction through the combined efforts of Development Services and the Denver Department of Transportation and Infrastructure (DOTI).
For Colorado developers working across the Front Range, including projects in Broomfield, Thornton, Parker, Castle Rock, and Commerce City, each jurisdiction operates under its own review framework while referencing state-level CDPHE stormwater standards. The same core principles apply: stormwater and wastewater must be engineered, permitted, and inspected before a project can be built.
Construction Activities Stormwater Discharge Permit (CASDP)
A Construction Activities Stormwater Discharge Permit (CASDP) is required for any project that meets the criteria listed below, or at the discretion of the Development Services engineer. Stormwater Management Plans are required for development activities that include:
- The disturbance of one acre or more
- Site development or redevelopment that is part of a larger plan
- Site development or redevelopment which has significant potential for erosion
- Construction activities on soils contaminated by hazardous pollutants
The Construction Plan and Drainage Report or the Sanitary Sewer Study are required at the discretion of the Development Services engineer. This study must be done by a licensed professional engineer like Michael Groselle, P.E. from Modern Engineering Solutions, who will prepare a site plan to show the extent of work proposed, existing topographical contours, grades and drainageways, proposed grades and profiles for roads, channels, and foundations, locations of existing drains and manholes, plans for structures, proposed treatment facilities, and proposed landscaping features such as curbs, sidewalks, and fences.
Note: Developments and projects over one acre (both residential and commercial) will also require a Construction Activities Stormwater Discharge Permit (CASDP).
For Colorado developments outside Denver’s jurisdiction, the Colorado Department of Public Health and Environment (CDPHE) administers the Colorado Discharge Permit System (CDPS) stormwater program. Projects disturbing one acre or more statewide are required to obtain CDPS permit coverage under the Construction General Permit, submit a Stormwater Management Plan, and maintain a site-specific erosion and sediment control program throughout construction.
What the Stormwater Management Plan Must Cover
A Stormwater Management Plan (SWMP) prepared for Denver or Colorado CDPS permit coverage is a site-specific engineering document that must address the full lifecycle of stormwater management from initial grading through final stabilization. A well-prepared SWMP is not a checklist. It is a technical document that reflects actual site conditions, drainage patterns, soil characteristics, and the specific construction sequencing planned for the project.
Key elements that belong in every Colorado construction Stormwater Management Plan include:
- Site map showing existing topography, drainage patterns, and proposed disturbance limits
- Best management practices (BMPs) for erosion and sediment control including silt fence, inlet protection, stabilized construction entrance, and temporary seeding
- Sequence of BMP installation relative to construction phasing
- Inspection and maintenance schedule for all installed BMPs
- Permanent stabilization plan showing final grades, seeding, and landscaping
- Spill prevention and response procedures for fuels and construction materials
For projects involving permanent detention and water quality facilities, the SWMP must also document how permanent infrastructure will be maintained after construction is complete. Denver’s Wastewater Engineering Department provides guidance for designing aesthetically enhanced detention ponds that meet both technical performance requirements and visual standards for urban and suburban development sites.
Step-by-Step: The Four-Stage Submittal Process
Step 1: Storm Drainage and Sanitary Sewer Submittal Requirements. The initial submittal package for Denver Wastewater Engineering review includes the Application to Construct (TEP Application), engineer’s certification, irrevocable letter of credit, certificate of inspection letter, title block, and Development Services Sanitary and Storm General Submittal Guidelines documentation. Each document must be prepared and certified by a licensed professional engineer. The submittal package establishes the engineering basis for the project and initiates DOTI’s technical review.
Step 2: Sewer Use and Drainage Permit (SUDP). The Sewer Use and Drainage Permit is the wastewater-specific permit for the project. SUDP review covers the sanitary sewer connection, capacity confirmation, and any required sewer main extensions or modifications needed to serve the development. For projects that require sanitary sewer main extensions, the engineering drawings must demonstrate that the proposed connection meets Denver’s sanitary design and technical criteria manual requirements, including minimum pipe slope, depth of cover, manhole spacing, and material specifications.
Step 3: Standards and Compliance. All technical design work must conform to Denver DOTI’s published standards and details, including the sanitary design and technical criteria manual, the sanitary sewer master plan, the storm drainage design and technical criteria manual, and the storm drainage master plan. Wastewater detail and technical specifications and standard detail drawings are available through the DOTI document center and must be incorporated into construction documents. For Colorado projects outside Denver, applicable state and local design standards govern in place of or in addition to DOTI requirements.
Step 4: Standard Fees. DOTI standard fees apply to all permit applications. Fee schedules are published by Denver’s Building and Land Development Fee schedule under DOTI/SUDP. Fee amounts vary by project type, size, and the scope of infrastructure being permitted. Confirming applicable fees before submittal prevents delays in permit processing caused by incomplete fee payment.
How MES Supports Colorado Developers Through the Process
The Denver Wastewater Engineering Department review process requires engineering expertise across storm drainage design, sanitary sewer engineering, stormwater management planning, and permit coordination. Each stage of the submittal has specific technical requirements that must be met correctly the first time. Submittals that arrive incomplete or with deficient technical documentation generate revision requests that add weeks to the review timeline.
Modern Engineering Solutions, led by Michael Groselle, P.E., works with Colorado developers across the Front Range to prepare complete, technically defensible submittal packages for Denver Wastewater Engineering review and CDPS stormwater permit applications. Our Colorado civil engineering practice includes direct experience with DOTI review requirements, CDPS stormwater permitting, and the coordination between Development Services and the Wastewater Engineering Department that determines how quickly a project moves through review.
Engaging a Colorado-licensed PE with Denver submittal experience before site planning begins allows the stormwater and sanitary sewer infrastructure to be designed into the project from the start, not retrofitted after the site plan is finalized. That sequencing protects the project schedule and prevents the redesign costs that consistently arise when infrastructure constraints are discovered after architectural and civil layouts are already complete.
Frequently Asked Questions
Does every Colorado development project need a CASDP?
A CASDP is required for projects disturbing one acre or more in Denver and for projects meeting CDPS Construction General Permit thresholds statewide. Projects between half an acre and one acre in Denver may require DOTI review and stormwater management planning even without a full CASDP, depending on the nature of the work and the receiving drainage system. The Development Services engineer has discretion to require stormwater management documentation on smaller projects with significant erosion potential or sensitive receiving water conditions.
What is the difference between a CASDP and a SUDP in Denver?
A CASDP (Construction Activities Stormwater Discharge Permit) covers stormwater management during construction: erosion and sediment controls, drainage infrastructure, and post-construction water quality. A SUDP (Sewer Use and Drainage Permit) covers the permanent wastewater connection: sanitary sewer design, connection authorization, and capacity confirmation. Most development projects of meaningful scale in Denver require both, and the two permit processes run through different DOTI divisions but must be coordinated to support a unified construction schedule.
Can MES prepare both the drainage report and the sanitary sewer study for a Denver project?
Yes. MES prepares both the storm drainage report and the sanitary sewer study required for Denver Wastewater Engineering review, as well as the Construction Plan, Stormwater Management Plan, and permit application documentation. Preparing all technical submittal documents within a single engineering firm eliminates the coordination gaps that arise when drainage and sewer design are split between separate consultants.
Need Engineering Support for a Denver or Colorado Development Submittal?
Modern Engineering Solutions, led by Michael Groselle, P.E., works with Colorado developers to prepare complete storm drainage reports, sanitary sewer studies, stormwater management plans, and permit applications for Denver Wastewater Engineering Department review and Colorado CDPS permitting.
We specialize in:
- Storm drainage design and Denver DOTI submittal preparation
- Sanitary sewer engineering and SUDP documentation for Denver developments
- Construction Activities Stormwater Discharge Permit (CASDP) preparation
- Colorado CDPS Construction General Permit stormwater management plans
- Civil-utility design coordination for Colorado Front Range development projects
Modern Engineering Solutions, McKinney, Texas and Golden, Colorado. Contact: (214) 833-6748 or mod-eng.com
