Stormwater runoff poses a significant threat to water resources throughout Anoka County. Stormwater volume and pollutant loads carried to receiving water bodies via stormwater infrastructure can have devastating effects on water quality and surrounding habitats.
In response to these issues, ACD staff conduct subwatershed stormwater retrofit assessments to identify retrofit opportunities in subwatersheds that are significant contributors to the degradation of high-priority water bodies. Projects identified as part of the assessment process improve water quality, increase groundwater recharge, and reduce stormwater runoff volumes throughout Anoka
County.
Step 1: Assessment Scoping –Refine the retrofit strategy to meet local restoration objectives
- Define core retrofitting objectives. Identify preferred retrofit treatment options.
- Delineate the subwatershed focus area. Step 2: Desktop Analysis – Search for potential retrofit sites throughout the subwatershed; secure GIS and other mapping. Conduct a desktop search for potential retrofit sites. Prepare base maps for field reconnaissance.
Step 3: Subwatershed Reconnaissance –Investigate retrofit sites in the field
- Verify drainage areas and mapping data. Assess site constraints
- Search for additional retrofit opportunities
Step 4: Treatment Analysis/Cost Estimates –Create project concepts and model for treatment potential
- Develop project concepts and cost estimates
- Model for volume and pollutant reduction
Step 5: Evaluation and Ranking –Compare projects throughout the subwatershed
- Conduct cost/benefit analysis for project concepts
- Rank projects by cost-effectiveness
- Compare results to restoration objectives
Step 6: Reporting – Create a detailed report of assessment findings and recommended projects
- Deliver final report to project partners
- Conduct one verbal presentation of assessment findings to project partners
Since 2011, ACD staff have completed eight subwatershed stormwater retrofit assessments. Targeted high-priority water bodies have included creeks, rivers, and lakes. See the Projects tab for the complete reports. Cities, watershed districts, watershed management organizations, or other local groups contract with the ACD to complete these assessments. Often, these groups lack staff with stormwater expertise, so hiring the ACD is cost-effective for everyone.
Subwatershed Stormwater Retrofit Analysis Reports
ACD Contact :