Retrofitting Stormwater Management Facilities – Benefits and Challenges

Presentation: PowerPoint 

Author: Juni Shahjabin Alam, P.E. Greenman-Pedersen, Inc. (GPI)

Abstract: This presentation focuses on the benefits of retrofitting existing stormwater management facilities and associated challenges. It highlights steps and considerations necessary in determining the feasibility of stormwater retrofitting as well as various criteria associated with proper implementation of stormwater retrofit projects. Retrofitting stormwater management facilities that had originally been designed for quantity control provides opportunity for water quality improvements while controlling downstream stormwater runoff. One of the main benefits of retrofitting is the ability to improve the performance of existing stormwater facilities while addressing additional existing deficiencies within and adjacent to the facilities. Although retrofitting appears to be the most obvious solution to improving stormwater pollutant discharge, there are several challenges that often eliminate retrofitting as a feasible option. These challenges include subsurface soil and groundwater conditions, locations of existing utilities, impacts to natural resources, neighboring land use conflicts, objections from adjacent property owners, and capital and maintenance costs – to name a few.