Abstract Archive Select a year below to view:

Hydrologic Performance and Life-Cycle Cost Analyses of Green Stormwater Infrastructure
Proceedings of the 2022 Mississippi Water Resources Conference

Year: 2022 Authors: Abera L.E., Surbeck C.Q., Alexander K.

Urbanization increases impermeable land cover by diminishing other permeable land covers such as grass and forests. This change affects the hydrology of urban areas and results in excess stormwater runoff or flooding events. A sustainable way to reduce the amount of impermeable surfaces and allow stormwater to infiltrate into the ground is to use green stormwater infrastructure (GSI). In this study, computer simulations were performed to assess the hydrologic performance of GSI in runoff reduction. Life-cycle cost analyses (LCCA) of stormwater infrastructure were also performed to determine the cost-effectiveness of GSI practices, considering capital and operation and maintenance (O&M) costs.

This presentation will show the economic and hydrologic analyses results of green stormwater infrastructure for a proposed development site in Oxford, Mississippi. The HydroCAD stormwater modeling tool was used to perform hydrologic modeling for three types of GSI: permeable pavement, rain garden, and grassy ditch. The site was modeled using the curve number reduction method, which reduced the weighted average curve number of the site when GSI was implemented. The peak flow and volume of stormwater runoff were estimated for multiple scenarios based on the city's design storms. Depending on the type and size of the GSI and the storm intensity, the simulation results showed that applying GSI reduced the volume of excess runoff by 12% on average. Of the three GSI scenarios, the rain garden resulted in the highest reduction in the volume of stormwater runoff. A life-cycle cost analysis was performed using the Water Environment Research Foundation (WERF) Low Impact Development Cost Analysis Tools. Based on the LCCA results, the net present cost of GSI scenarios is higher than for traditional stormwater infrastructure. However, the LCCA does not include other external factors, such as environmental and health benefits. A co-benefit analysis was conducted using the Community-enabled Life-cycle Analysis of Stormwater Infrastructure Costs (CLASIC) tool to quantify these benefits.

Tweets by @MS_WRRI