Green infrastructure is an approach to managing rain water and stormwater runoff in a way that protects, restores, or mimics the natural water cycle.
Green infrastructure combines natural and engineered systems (plants as well as pipes, soil, and stone) to slow down the flow of stormwater runoff, filter it, and, where possible, soak up water or infiltrate runoff back into the ground. It's a revolution in stormwater management that will be a big part of the solution to reducing runoff and protecting and restoring the health of Long Island Sound and its tributaries.
Save the Sound collaborates with grassroots organizations and municipalities across Connecticut and eastern New York to help develop, design, and implement green infrastructure projects in high priority watersheds. Our projects range from small to large and include installing residential rain gardens to capture and infiltrate roof runoff for groundwater recharge in Southington and New Haven, CT, collaborating with city officials in coastal Connecticut to evaluate the feasibility of green infrastructure (read the Hazen & Sawyer report here), helping to design and build bioswales to reduce stormwater runoff and combined sewer overflows to urban rivers and the Sound, and partnering with Sunken Meadow State Park and numerous agency partners to restore floodplains and riparian buffers by removing unnecessary impervious surfaces and replacing pavement with enhanced green space.
Follow the image links below to learn more about our green infrastructure projects in Connecticut and eastern New York.
Save the Sound facilitated the preliminary design process for four large-scale green infrastructure projects in downtown Bridgeport. The Bridgeport Water Pollution Control Authority along with project engineers at Arcadis honed in on four sites where green infrastructure could help to disconnect impervious surface from the combined sewer system including sites at Housatonic Community College, on State Street, John Street and in the plaza in front of People's Bank on Main Street.
The project concept for Housatonic Community College involves capturing stormwater runoff from the roof deck of the campus parking garage. Once built, the project will capture runoff from over 2 acres of impervious surface and divert up to 1 million gallons of stormwater from the combined sewer system each year. The design for the project is complete and is under review at the Connecticut Department of Energy and Environmental Protection.
The design calls for retrofitting the lawn on the south side of the parking garage with a large rain garden. The rain garden, as designed, will receive overflow from a special rain water retention planter on the west side of the garage as well as some runoff from Lafayette Avenue. The garden will enhance the currently grass covered lawn with a plethora of native plants, which will provide habitat for birds and pollinators while soaking up and filtering stormwater runoff.
The concept for State Street, on the north side of the US District Courthouse, calls for replacing a paved buffer zone with stormwater bump-outs--or planted depressions that will soak up and infiltrate rain water that flows off of the road way and sidewalk between Route 8 and Lafayette Boulevard.
The four conceptual designs include plans for a retrofit to the large impervious plaza at People's Bank.
While this is private property, retrofitting the plaza with bioswales and tree planters would benefit the public by reducing the volume of stormwater water getting into the combined sewer system, which causes overflows of untreated stormwater and raw sewage into the nearby Pequonnock River.
A fourth project is in design for downtown Bridgeport, which calls for enhancing John Street with improved tree pits and porous sidewalks. The retrofits, which would be carried out on city property, would help to manage runoff from John Street as well as from a private parking lot just uphill of the site.
The sidewalk on John Street is in bad shape. Green infrastructure retrofits along this corridor would capture and divert stormwater from the combined storm sewer system, while also enhancing and improving conditions for pedestrians.
Connecticut's Beardsley Zoo, Bridgeport
In November 2015, Save the Sound launched our collaboration with the City of Bridgeport and Connecticut's Beardsley Zoo. The project is a part of the Zoo's Green Infrastructure Long Range Plan, which aims to develop projects that will capture and filter stormwater runoff to help protect water quality in Bunnell's Pond and the Pequonnock River, downstream.
Save the Sound kicked off our efforts to retrofit the parking area at Connecticut's Beardsley Zoo in November 2015. For the project, we helped design and construct green infrastructure retrofits identified in the Zoo's Long Range Plan.
Green infrastructure retrofits to the parking lot will help to educate over 275,000 annual visitors to the zoo about the function and efficacy of porous pavement and rain gardens.
Eventually, the zoo hopes to carry out all phases of their Master Plan.
We constructed a walkway with porous pavers--which are like regular bricks that allow rain and stormwater runoff to flow through the spaces between them, and into the ground below. The gravel layer filters the stormwater before it seeps into the ground below.
The porous walkway and rain garden work together to capture and filter stormwater runoff from 1/4 of an acre of parking lot at the Beardsley Zoo.
Youth from Groundwork Bridgeport, the Beardsley Zoo Conservation Discovery Corps, Beardsley Explorers, and the Mayor's Conservation Discovery Corp joined Save the Sound for a full day green infrastructure workshop and rain garden planting.
With the help of over 35 youth from four Bridgeport-based environmental groups, we planted over 80 perennials and four trees that will intercept rain water and filter stormwater runoff from a parking lot at the zoo.
Some of the perennials that we planted in the rain garden include arrowwood viburnum, northern bayberry, winterberry, heavy metal switch grass, and black-eyed Susans.
We planted four trees, including two types of native dogwood, a serviceberry, and a red maple cultivar.
Save the Sound staff collaborated with Beardsley Zoo and Groundwork Bridgeport to lead a rain garden and tree planting workshop for over 35 teenagers.
The rain garden and porous walkway will capture and filter over 200,000 gallons of stormwater runoff, annually.
West River Watershed, New Haven
Cities are full of impervious surfaces like roof tops, sidewalks, and roadways that prevent rain water from soaking into the ground. Rain flows over streets picking up grease, oil, metals, and other contaminants and then flows into our rivers and the Sound untreated. In cities like New Haven, where stormwater and sewage travel through the same pipes called combined sewers, which are designed to overflow, even small storms can cause untreated effluent to overflow into rivers and the Sound.
Save the Sound's first green infrastructure project in New Haven was a bioswale, located in front of the Edgewood Interdistrict Magnet School. We collaborated with the City of New Haven Engineering Department to draft designs, and then hired the Urban Resources Initiative, who worked with the Emerge workforce reentry crew to construct and plant the 280 square foot bioswale.
An assortment of bird and pollinator friendly native grasses, sedges and other perennials were included in the planting plan.
The bioswale captures runoff from over 11,000 square feet of roadway and sidewalk, and disconnects the last section of combined storm-sewer system along Yale Avenue.
This is the bioswale in full bloom during its first growing season.
We worked with a designer and illustrator to create a fun educational sign next to the bioswale.
A bioswale is like a filter and a sponge. Plants and mulch on the surface capture pollutants that rain picks up off of the road surface. The plants soak up the water and use it to grow. Their roots and the soil and stone below the surface help to filter the water even more before it soaks into the ground.
Save the Sound worked closely with the City of New Haven Department of Engineering and Department of Parks Recreation and Trees to design and build two rain gardens along Edgewood Avenue between Ella T Grasso Boulevard and Ellsworth Avenue. The two rain gardens will intercept stormwater and help reduce the occurrence of combined sewer overflows to the West River, downstream.
Save the Sound collaborated with the City of New Haven, the Friends of Edgewood Park and the East Edge Gardeners to design two 400 square foot rain gardens in New Haven's West River Watershed.
Over 30 volunteers from the neighborhood and throughout the region helped up to plant 450 plants in the two rain gardens.
Volunteers joined Save the Sound staff to construct the two rain gardens, which capture stormwater runoff from Edgewood Avenue and prevent it from entering the cities combined sewer system.
The bioswale was bursting with color during its first growing season.
Sunken Meadow State Park, Long Island
Save the Sound and our project partners are working to reduce runoff from a 14-acre parking lot at New York's Sunken Meadow State Park. The parking lot is closed to visitors with the exception of peak days, such as the 4th of July. We are working with the park to identify alternatives to impervious pavement in order to reduce stormwater runoff while still accommodating the parks many visitors.
Our next phase of work in the park will build on the success of the post-Sand tidal reconnection and bridge installation project completed by Save the Sound and the New York State Office of Parks, Recreation and Historic Preservation (OPRHP) at the park in the fall of 2013. Using a design managed by Save the Sound, OPRHP replaced two deteriorated culverts washed out by Storm Sandy with an open channel pedestrian bridge. That returned natural tidal flow to 132 acres of deteriorated salt marsh.
Our project at Sunken Meadow State Park is a part of a mulit-year multi-faceted restoration effort, and includes parking lot retrofits to reduce runoff as well as marsh restoration plantings that will enhance recently reconnected salt marsh with over 10,000 native plants.
Sunken Meadow State Park features include 483 acres of coastal forest, 81 acres of low salt marsh, two acres of marine eelgrass, 54 acres of tidal creek, and 34 acres of maritime dunes.
Quinnipiac River Watershed Aquifer Recharge Project
Contamination of groundwater aquifers by a leaky landfill in the Quinnipiac River Watershed led to the closure of important water supplies and drinking water resources. Save the Sound partnered with UCONN, CT DEEP and several watershed towns to use techniques like rain gardens and porous pavement to capture, filter and infiltrate stormwater to help replenish groundwater, recharge aquifers and protect drinking water resources.
Save the Sound developed a comprehensive outreach campaign to connect with homeowners in Aquifer Protection areas throughout Southington, the town hardest hit by the closure of the drinking water aquifer. We reached out to 3,000 residents with a combination of informative mailers and public presentations. 60 households applied to be a part of our rain garden incentive program. 12 households met all of the incentive program criteria. We planted 9 rain gardens in the summer of 2013.
Dozens of volunteers participated in nine residential rain garden planting workshops.
We collaborated with homeowners in the town of Southington to capture roof water, disconnect downspouts, and divert flow into rain gardens. This rain garden, on Tanglewood Drive, fills up with rain water during a storm. The plants, mulch and soil filter the water before it soaks into the ground.
Save the Sound also collaborated with the towns of Wallingford and Plainville to retrofit public parking lots with porous asphalt.
Porous pavements, like the porous asphalt shown here, allow water to seep through the pavement and into the ground below. Pore spaces in the pavement trap sediments and filter out pollutants. Additional filtration is provided by layers of gravel and stone before the stormwater enters the ground below.
Save the Sound worked with the Town of Plainville to pull up 3,000 square feet of pavement and replace it with porous asphalt. A gravel bed, like the one being installed in this picture, is an integral part of a porous pavement installation. The gravel provides stability for the porous material, while providing a storage area and filtration for water that soaks through the pavement.
Once installed, porous asphalt resembles standard asphalt--but has numerous environmental benefits. If properly maintained, porous pavements can be an effective way to mitigate stormwater runoff from parking lots, sidewalks and city streets.