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Case Study Location: Colorado: Douglas County

Case Study Title: A Comprehensive Erosion Control Permit Program

Minimum Control Measure: Construction site stormwater runoff control

Ten Elements of an Effective GESC PlanDouglas County, Colorado, is one of America’s fastest growing counties. In the decade between 1990 and 2000, its population nearly tripled. To address its high growth rate, the Douglas County Construction Site Runoff Control Program (hereafter referred to as The Program) developed a successful permit review, issuance and inspection process, and wrote a comprehensive Grading, Erosion and Sediment (GESC) Control manual.

Location: Colorado: Douglas County
Annual Rainfall: 17 inches
Population: 175,766
Year the Program Started: 1993

Contact Information:

Douglas County Public Works
100 Third St
Castle Rock, CO 80104
Phone: (303) 660-7490  


Scenic image of Douglas County

Douglas County's new Grading, Erosion and Sediment Control Manual (hereafter referred to as the Manual) has streamlined the review and approval process for Stormwater Pollution Prevention Plans (SWPPP), increasing the effectiveness of submitted plans and reducing the number of violations.

Issuing Permits

Under state law, Colorado may accept only SWPPPs developed by state-registered engineers or by qualified designers under the direct supervision of professional engineers.

Before a SWPPP is developed, the applicant and the applicant’s engineer are encouraged to conduct a presubmittal meeting with Douglas County staff. During the meeting, all parties discuss Douglas County ’s requirements, which helps accelerate the plan review and approval process.

Staff members and the applicant's engineer complete checklists contained in the Manual. Standard notes and references contained on the Program's website discuss each sediment and erosion control measure. Additionally, staff ensures that the applicant understands the initial and long-term costs of the best management practices (BMP).

After the presubmittal meeting, staff pre-reviews the SWPPP for completeness. The process takes about seven days. If incomplete, the application is returned to the applicant for revision. Staff members then conduct a 25-day-long comprehensive review of both the SWPPP and the completed permit application. Program staff members follow up with a second review of the corrected plan, a process lasting up to 25-days.

Once approved, Program staff approves the SWPPP and the applicant submits a permit fee of $250 plus $25 per acre of disturbance. The applicant also must post a fiscal security fee prior to scheduling the preconstruction meeting. The fee - a letter of credit or a cash deposit – is deposited in a non-interest bearing account for at least two years.

In contrast to a bond, Program staff members have found letters of credit or cash deposits convenient when remediation for excessive violations is necessary. Although rare, staff members have in the last two years used an applicant's security fee. One developer, for example, couldn't finish the project because he went bankrupt.


Scenic image of Douglas County The Program employs three full-time grading, erosion and sediment control inspectors, six engineering inspectors, seven review engineers, a development review manager, environmental, drainage and stormwater management engineers, water quality technician, agreements technician, permits and inspections manager, and Director of Engineering Services.

To satisfy the Program's rigorous specifications, staff members conduct several types of inspections.

  • Preconstruction Inspection – The GESC inspector, applicant, contractor and subcontractors working under the SWPPP meet at the site. There the inspector makes sure the applicant understands the permit's requirements and confirms the placement of all pre-construction BMPs.
  • Topsoil Stripping Inspection – After the topsoil is removed, an inspector verifies that the topsoil is preserved, properly protected and prevented from running-off the site.
  • Periodic BMP Inspection – An inspector certifies that the SWPPP’s BMPs have been installed and maintained.
  • Change-in-Manager Inspection – An applicant must inform CSRC staff within seven days if the SWPPP manager changes. An inspector then visits the site and makes sure the new manager understands their responsibilities under the permit.
  • Phased Construction Inspection – Required for projects 40 acres or larger, phased construction inspections occur during each phase of construction, if phased construction is part of the SWPPP plan.
  • Initial Close-out Inspections – An inspector confirms the removal of all unnecessary BMPs.
  • Periodic Vegetation Inspection – An inspector verifies the planting and satisfactory growing of final vegetation. Applicants must inspect seeded areas monthly for two years.
  • Vegetation Acceptance Inspection – An inspector ensures the growth of required vegetation, to a standard of three plants per square foot, with no bare areas larger than two-square-feet.
  • Final Close-Out Inspection – After the removal of temporary sediment and erosion controls, the inspector confirms the removal of all temporary BMPs, the installation of all permanent BMPs, and the return of the fiscal security deposit.

Applicants must pay a $50 re-inspection fee for missed appointments with Program inspectors, or for site violations requiring re-inspection. The fee offsets increased taxpayer costs resulting from multiple inspections of non-compliant sites. If issued a stop-work-order, the applicant must immediately correct the deficiencies, reapply for a GESC permit, and then repay the fee. If the applicant conducts on-site work without a valid Program permit, the applicant's permit fee triples. Chapter 5 of the GESC manual outlines all enforcement procedures.


The CSRC staff has seen significant reductions in review and plan-approval times. Many plans are now approved on their first submission. Staff members have also seen an increase in the comprehensiveness and effectiveness of submitted Program plans. And finally, staff members have seen violations drop significantly, a trend they attribute to the new GESC manual and the longevity of the program.

Additional Materials Related to this Case Study:

Additional Resources and Tools for this Minimum Control Measure

EPA presents this case study as an example to which Phase I and Phase II municipal stormwater programs can refer as they develop their own stormwater programs. Although EPA has reviewed the case studies, they should not be considered officially endorsed by the Agency and are not intended to represent full compliance with EPA’s stormwater Phase II minimum control measures. Each community must decide on the appropriate BMPs necessary to meet its unique permit requirements and local conditions.

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Last updated on June 08, 2007 9:09 AM