8.1 SR 10-18-2021 - Laserfiche WebLink

Home Browse Search

Stormwater The City of Elk River is responsible for its stormwater management system. Through the city's Stormwater Management Plan, Elk River maintains a system of catch basins, pipes, ditches, and detention ponds. There is no Watershed District or Water Management Organization with jurisdiction in the city. This means the city is regu- lated as a Municipal Separate Storm Sewer System (MS4) community, responsible for compliance with National Pollution Discharge Elimination System (NPDES) permit- ting requirements, including its Stormwater Ordinance and the Stormwater Pollution Prevention Plan (SWPPP). Encourage the Integration of Ponds in Developments as a means for Stormwater Management With nearly 400 stormwater ponds in the city's system, ponds are a major component of water management in Elk River. Stormwater ponds enable treatment of drainage in ways, such as the settling of sediment particles, which can accumulate over time and require maintenance to ensure performance of the system. The city should continue to monitor its stormwater ponds and incorporate pond issue resolution into other development projects like it did with the 269 Redefine project. Implement Green Infrastructure As the State of Minnesota has experienced more intense rain events, green infrastructure offers cost-effective, resilient approaches to management of wet weather impacts. The definition of "green infrastructure" goes back to the Clean Water Act, in which it is identified as a range of measures such as plant or soil systems, permeable surfaces, or landscaping to store or infiltrate stormwater and reduce flows to sewer systems or to surface waters. Single purpose "gray stormwater" infrastructure (conven- tional piped drainage) works to move stormwater away from the built environment. Conversely, green infrastruc- ture reduces and treats stormwater at its source, while often providing other environmental, social, or economic benefits. Most of Elk River has soils that are conducive to green infrastructure principles; that is, the soils tend to drain well. In some locations near water supply wells, the application of green infrastructure infiltration measures needs to be done with care to ensure contaminants are not introduced to the water supply. The schematic below provides an overview of the spectrum of stormwater control practices from green to gray infra- structure. As Elk River grows and considers new opportu- nities for optimizing its investments in the built environ- ment, green infrastructure practices should be evaluated. While helping to mimic or restore natural hydrology to areas, it may also create secondary ecosystem benefits with natural habitat, water purification, erosion protection, and a more sustainable urban environment. Stormwater Control Measures (SCM) Natural Areas Stormwater Ponds Rain Filtration & & Wetlands Garden Infiltration Basin Intact forests, SCMs capable of vegetated SCMs in Surface SCMs like Wetlands, and other providing habitat and urban or suburban sand fitters within undeveloped areas resembling natural settings minimal vegetation areas Green Infrastructure Temporary Underground Conventional Flood Storage Storage Drainage Surface SCMs like Underground SCMs, Urban drainage dry ponds with potentially including strategies, primarily minimal vegetation storage, filtration, or concrete-basedwith or infiltration infiltration limited infiltration or storage Gray Infrastructure Source, Taguchi W, Weiss PT, GullrverJ$ Klein MR, Hozalski RM BakerLA, nclaiJC, KeelerBL, NieberJL.Itls NotEasyBeing Green Remgnizing Unintended Consequences ofGmen Stororwaterinfiustructure Water. 202012(2).522, https.Ildoi.org4o.3390IM2020522 100 Infrastructure • Elk River Comprehensive Plan I97CL\aIII M91A0:051IMAVE9701wo