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New Brighton/St. Anthony Basic Water Management Project – Phase 1 Rice Creek Watershed District 5555-221 Revised Final 18 June 10, 2014 Water Reuse is the process of capturing stormwater runoff and utilizing it for another purpose. A common reuse is for irrigation of managed turf areas such as athletic fields. Water reuse has been incorporated into the District volume control rules for development and redevelopment. Volume control BMPs should be considered as options to address the goals and objectives, but it is important to understand their limitations for addressing the existing regional flooding issues. Infiltration practices require specific site conditions, such as well-draining soils and sufficient separation from groundwater levels that are not commonly present in the RCD 2, 3, and 5 contributing drainage area. Evapotranspiration and water re-use practices generally treat runoff at site-level scale and thus have little impact regionally until numerous practices are in place. Volume control BMPs typically provide little relief for larger (>50-year recurrence) rainfall events since the storage volume provided by these practices is a fraction of the runoff volume generated by these events. 4.4 FLOODPROOFING Flood proofing is any measure, structural or non-structural, intended to prevent or reduce damage from flooding to structures. Flood proofing is typically utilized when other project types cannot sufficiently or feasibly mitigate the flood risk. The factors that dictate whether flood proofing can provide adequate protection include: x The height of maximum flood level on the structure x Velocity of water near the structure x Duration and frequency of floods x Economic considerations 4.5 PROJECT TYPE ASSESSMENT SUMMARY It is clear that conveyance modifications and the addition of detention storage in a system can be effective at lowering flood elevations and reducing peak flows when site conditions allow doing so. Floodproofing is also seen as a viable alternative when it’s economically feasible, and volume control potentially can reduce smaller-scale flood flows when it can be implemented effectively on a large enough scale. Factors such as adverse downstream impacts and their mitigation costs will be considered during the comprehensive analysis. It is likely a combination of project types will be recommended during the Phase 2 analysis to address the local and regional flooding issues and meet the defined goals and objectives in Section 2. The project types recommended in Phase 2 will depend on a flood prone area’s site constraints such as location, land availability, soils, sensitivity of downstream areas and the ability of regional approaches to effectively address issues. 80