Loading...
HomeMy Public PortalAboutNorth-Sarah-Phase-II_FINAL North Sarah Phase II North Sarah, a Central West End mixed-use development managed by the St. Louis Housing Authority, completed a rainscaping project in 2016. The project disconnected downspouts and redirected them into catch basins, piping the flow through a French drain infiltration system, and redirecting overflow into a drainage aggregate under the development’s parking lots. In addition, bump-outs with rain gardens were added to filter rainwater runoff before it enters the sewer system. The project proposed to retain nearly 138,000 cubic feet of rainwater each year. “The St. Louis Housing Authority and its development partner, McCormack Baron Salazar, have a dedicated team that has designed many development projects to be a beacon in the community representing the best practices in environmental sustainability,” said Cheryl Lovell, executive director of the St. Louis Housing Authority. “The MSD program allowed the team to pursue projects that even further reduced the development’s impact on the environment with techniques that may not have otherwise been economically feasible.” Rainscaping type: Permeable pavement and curb bump-outs Challenges: The major goal of the project was to capture as much water as possible on the site, said project engineer David Johnson of David Mason & Associates. This was especially challenging considering the parking lot’s location behind the building – typically developments are graded back to front and down to the street level. Directing water to the lot instead of down the street to the sewer system required an unconventional design. In addition, there was a learning curve with this project, particularly in implementing fairly new best management practices (BMP) technology. For instance, when it was discovered that previously installed pervious asphalt pavement was not installed according to the BMP, it needed to be removed and replaced. Solution: To maximize water capture, the project took advantage of the entire footprint of the parking lot – the stalls are permeable pavement, the drive aisles are conventional pavement, and the area underneath the lot serves as the drainage aggregate. “There is a clean rock layer underneath the lot where water can collect and be filtered before slowly releasing to the sewer system,” said Johnson. Because most rain events in St. Louis are 1.18 inches or less, he added, the system is designed to retain and filter water up to 1.18 inches of rainfall. What makes this project unique: North Sarah Phase II gave MSD an opportunity to partner on a project that meets affordable housing needs in the urban core. It also provides good visibility of the benefits of rainscaping – all residents will receive information and training on the sustainable features included in their new community. “The North Sarah Phase II project demonstrates how green infrastructure features can not only be applied to the redevelopment of distressed urban neighborhoods, but also reduce runoff while enhancing the neighborhood’s appearance,” Lovell said. About MSD’s Rainscaping Large-Scale Grant Program: This rainscaping grant program (previously called the Early Action Program) seeks to engage partners to identify joint opportunities to incorporate rainscaping into ongoing programs and future redevelopment projects. Each grant awarded allows MSD to create a public- private partnership that contributes to the environmental, social, and economic health of the St. Louis region. For more information or to learn how to apply for your organization, visit projectclearstl.org.