Approximately 2.5 acres of land at Hamden Town Center Park are being upgraded from lawn to a large-scale rain garden to help filter stormwater, restore habitat, and create a greener and more resilient town of Hamden. Construction for this transformation, led by Save the Sound, has started and will continue through May. Volunteer opportunities will be announced early summer to engage the community in this green infrastructure effort by planting over 7,000 native grasses, flowers, and shrubs.
Currently, stormwater runoff from an 88-acre urban watershed flows from impervious surfaces along Dixwell Avenue and neighboring streets and homes into storm drains and through a pipe which directly discharges stormwater into Town Center Park. After even moderate rainfall —less than one inch— this system quickly becomes inundated, offering little to no treatment of sediment or pollutants. In heavy rains, runoff often sheet flows onto the lawn and directly into Pardee Brook diversion channel, which flows into the Mill River. Untreated stormwater that enters our waters leads to health hazards such as E. coli outbreaks and other pollution-derived ecological reactions. Treating this runoff will improve the water quality of the Mill River and Long Island Sound.
To treat runoff at Town Center Park, Save the Sound will work with the Town of Hamden to construct a large-scale rain garden at the outfall of the drainage pipe. Rain gardens are a form of green infrastructure that help filter pollutants from stormwater as it flows from hard, impervious surfaces such as roads, sidewalks, and roofs to the nearest waterway. They are strategically designed with layers of soil, sand, and rock and include native plants, which together act as a sieve to remove a variety of pollutants. Fertilizers, road salt, and chemicals are trapped in these layers and in roots of plants, cleaning the water before it enters the waterbody.
“The project is expected to manage over 20 million gallons of stormwater each year from the surrounding drainage area, improving the water quality and restoring the natural hydrology of Shepard Brook and the Mill River,” says project lead, Nicole Davis. “In addition to water treatment, this rain garden will restore habitat for native flora and fauna and provide a pocket of nature to be enjoyed by the community.”
During April, Hamden Department of Public Works will enhance the pool at the base of the stormwater pipe, create a stormwater channel, and install a larger rain garden to capture stormwater. In May and June, two volunteer planting events will be announced as the work comes to a close. We welcome you to join us at the Hamden Earth Day Festival on April 22, from 10 a.m. to 3 p.m. at Hamden Town Center Park at 2761 Dixwell Avenue to visit the site and learn more about the project.