Glenwood Springs Drainage Mapping

Overview

The City of Glenwood Springs has been growing in population significantly in the past few years. This means that the city increasingly needs to meet State Municipal Separate Storm Sewer System (MS4) criteria. The purpose of this project is to evaluate several components of the current stormwater infrastructure and determine if and what improvement is necessary for an MS4. Therefore, the team conducted code and site analyses to discover the current state of the infrastructure, i.e., pipe and culvert locations, sizes, and the required capacity of that infrastructure. Hydrologic analyses were performed using HEC-HMS and the EPA Stormwater Calculator to determine the expected flow in each area for the appropriate design storm. The data gathered was then used to construct HEC-RAS models that showed that improvement was necessary for two areas specifically. These models were then used to iteratively design new culvert dimensions necessary to pass the design storm flows. Finally, 10% design Civil3D drawings were produced specifying essential design criteria; and early cost estimates were made. The solution is comprised of 9 proposed concrete box culverts strategically located throughout the drainage system. These new culverts can dramatically increase the city’s safety from floods and are an improvement on the existing infrastructure because they are corrosion resistant and more durable than the already present CMP culverts.