ES&S was engaged to evaluate the City’s storm water management system, offer recommendations for storm drainage improvements (SDI), and provide design services for the implementation of projects. The initial project scope called for analysis of an approximate 300-acre study area encompassing the bulk of the city’s east side. In scoping discussions, it was decided to focus on a 60-acre segment on the south end of the study area where there were known drainage issues.
The study evaluated potential improvements (diversion, stabilization, enclosure) of some natural drainage paths within this sub-basin, mitigating impediments along 14th Street, and the potential benefit of redirecting portions of the flow to a 20-acre City-owned parcel that might serve a dual recreational purpose. A HEC-RAS model was created to determine the flooding impacts in the south study area associated with various storm intensities, concept-level drainage system improvements to mitigate these storm events, and opinions of cost developed to allow the City data to determine how to fund future capital projects. Downstream impacts will need to be considered with removal of flow impediments along 14th Street.
The City’s Storm Water Committee served as the management group for the Next Step Study, and wished to identify localized drainage issues to be considered in the study recommendations. The public outreach effort was primarily focused around a GIS-driven “virtual input portal” as a means to gain public comments over an extended period in a more efficient and cost-effective manner than holding a single (or multiple) public meeting. The site was active in early February 2020 and was open for several weeks. Coincidentally, in the weeks that followed, this turned out to become a much more routine means of stakeholder outreach due to the restrictions associated with the Covid pandemic.