Stormwater Management Takes The Field
Score a victory by incorporating infrastructure to mitigate flooding
By Thomas P. Shay
Photos: Woodard & Curran, Inc
Many parks, recreation, and athletic facilities serve as community hubs where residents gather to compete, play, socialize, and enjoy the outdoors. These prized community assets can play an even bigger role by incorporating infrastructure to manage stormwater, mitigate flooding, and achieve water-quality goals. Addressing stormwater challenges and needs in parks is a great opportunity for communities across the country, from the water-rich Northeast to the drought-stricken Southwest and everywhere in between.
Many of these facilities are in floodplains, near streams and rivers, or embedded in dense neighborhoods. This makes them ideal locations to house a wide range of infrastructure, including stormwater retention and treatment systems, or as a floodplain. When properly designed in alignment with stormwater-management goals, such facilities can become an essential piece of a community’s stormwater-management strategy.
From the perspective of those tasked with managing municipal parks, finding new ways to invest in these spaces can be powerful. Many communities struggle to fund ongoing maintenance and rehab of these spaces, which are often impacted by severe weather, rendering them unusable during and after heavy rains. Seeing parks as part of the solution to flooding and stormwater quality requires more sophisticated engineering on these properties, improving their performance and availability. If this is done properly, it creates powerful, multi-benefit projects that increase resiliency and create community.
This multi-benefit approach becomes possible when municipal departments collaborate on planning efforts. Parks and recreation facilities are municipally owned, abundant, and often larger open spaces in areas that tend to be low lying, with some form of drainage infrastructure present within or adjacent to the facility. The facilities also tend to need comprehensive maintenance or complete renovation. Municipal master-planning processes should evaluate parks and open space as potential locations for new infrastructure. Floodplain managers should also be aware of which public facilities are located within areas prone to flooding. Parks and recreation and public works departments should coordinate with floodplain managers to identify projects that can achieve as many objectives as possible for the community, especially where these outdoor facilities are often impacted by severe weather. This cooperative approach can create win-win scenarios that increase funding opportunities to improve amenities for the community, reduce stormwater runoff, improve water quality, and improve community resiliency.
Many communities consider multi-benefit projects but end up unsure how to fund the work or feel the work would be difficult, so they don’t take advantage of the opportunity to leverage infrastructure projects that can achieve many goals. These projects certainly necessitate greater capital investments, are more complex to design, require more permits, and take more effort overall. However, multi-benefit projects can generate more value and a greater return on investment if executed properly, and with consideration for the triple bottom line of financial, environmental, and social value. Well-executed (and coordinated) master planning efforts and feasibility studies are a means to increase the probability of a successful multi-objective or multi-benefit agenda.
Several communities have approached stormwater management as a joint effort with municipal departments, producing successful outcomes from which other municipalities can learn. In Portland, Maine, a combined sewer-overflow storage facility under an existing park will capture the first inch of rainfall to improve water quality while also creating a less flood-prone recreational soccer field. Officials in Quincy, Mass., purchased flood-prone properties to address resiliency while also expanding the campus and creating new athletic facilities for the public schools. Floodplain storage and water-quality improvement efforts were incorporated into redeveloping a public park owned and operated by Westchester County, N.Y. In Inglewood, Calif., residents will soon see improvements to a park as part of Los Angeles County’s initiative to improve surface-water quality.
Stormwater Management Under The Pitch
Combined sewer separation has been a critical part of the city of Portland, Maine’s Long-Term Control Plan for nearly three decades. City officials identified the Back Cove South Storage Facility in 2015 as an opportunity to reduce combined sewer overflows (CSOs) into Back Cove, which flows into Casco Bay and the Atlantic Ocean. The main goal of the project is to reduce the annual overflow volume of three CSO outfalls from 150-million gallons to approximately 18-million gallons. The four subterranean, cast-in-place concrete storage tanks will capture the first inch of rain during a storm event, or up to 3-million gallons prior to being pumped, treated, and discharged to Casco Bay. The tanks are located under an existing soccer field.
The scope of the project also included a redesign of the flood-prone soccer and multi-purpose fields and a segment of trail. Once complete, the new field will be reestablished above the 100-year flood level, landscaping will improve the trail-user experience, and underdrain and irrigation systems will help the city maintain the new field.
Dredging Up New Ideas
V. E. Macy Park, located in Ardsley, N.Y., along the Saw Mill River, is 172 acres of land owned and operated by Westchester County. As the county sought to redevelop a 10-acre area of the park, including new ballfields, improved vehicular and pedestrian access, and landscaping, the county also had to handle dredge spoils located in the river’s floodplain and incorporate stormwater-management and flood-mitigation measures.
Local and state regulations prohibited filling within a floodplain, and also required any dredge spoils to receive a minimum amount of cover soil and vegetation. The design included extensive cut and fill analyses to identify a solution that would balance floodplain impacts with soils-management costs, ensure a stable base for structures such as backstops, and create four better-performing, natural-grass athletic fields while avoiding settlement issues. The modeling and analyses informed a soils-management plan that avoided removing dredge spoils and provided additional flood storage capacity, while also improving ADA accessibility, safer pedestrian and vehicular circulation, and Low-Impact Development (LID) techniques, such as porous pavement in the parking lot and paths.
A Is For Athletic Fields
Situated on the coast just south of Boston, Quincy, Mass. has experienced frequent and severe flooding. The city has partnered with stormwater and floodplain experts to develop projects that both mitigate flooding and improve community facilities. One such project tied into the development of a new multi-sport, synthetic-turf athletic field for North Quincy High School. After evaluating four site options, the city chose to redevelop what became Creedon Field, and to do that, the city first had to rehabilitate an existing field to accommodate the increased activity while Creedon Field was under construction.
To begin developing the new Creedon Field and creating an expanded high school campus, the city needed to purchase nine homes to create adequate space. The homes acquired by the city sat within the floodplain, the subsurface conditions were less than ideal, and the presence of wetlands and soft soils throughout the site made it more challenging. However, the project allowed for significant infrastructure improvements, including compensatory storage within the floodplain that addressed these complex environmental, hydraulic, hydrologic, and geotechnical challenges, creating a better campus atmosphere and expanded programming opportunities for the community.
Historic Park Doubles As Watershed Juncture
In Inglewood, Calif., the 55-acre Edward Vincent Jr. Park was identified by a regional stormwater quality-management program as an ideal location for a regional stormwater-capture project. Funding through the Los Angeles County Safe, Clean Water Program supported a feasibility study, including hydrologic and hydraulic modeling for the contributing 895-acre drainage area. This analysis helped estimate the project’s pollutant load reductions to meet water-quality objectives established by the Los Angeles Regional Water Quality Control Board.
As a result, several opportunities were identified to reduce stormwater pollutant loads, while also improving the park. Now moving towards the design phase, the project will incorporate storm-drain diversions, an 8-million-gallon infiltration gallery beneath the rehabilitated baseball fields, a dry creek channel, and a bioretention area with trash capture and sediment forebay, as well as additional native vegetation and shade trees, new trails, a boardwalk, additional seating areas, improved public safety, and educational opportunities throughout the park.
Taking The Lead From Other Communities
While there is no one-size-fits-all solution or easy button, approaching this opportunity with a more diverse and inclusive team, engaging with stakeholders, completing and coordinating master planning, pooling funding, completing feasibility studies, and creating a phased implementation plan that prioritizes projects will increase the probability of generating multi-benefit solutions, a higher return on investment, and happy constituents. Communities looking to marry stormwater management with parks and recreation projects can look to other municipalities for inspiration to see what has and has not worked. Regardless of the approach, there are ample opportunities to leverage public open space for these multi-benefit projects to improve stormwater management and parks and vice versa. This type of multi-benefit approach is a win-win for all involved, financially, environmentally, and socially.
Thomas P. Shay, PE, is a principal and senior technical manager at Woodard & Curran, an integrated engineering, science, and operations firm. He specializes in site civil engineering and sports and recreation facility design. Contact him at tshay@woodardcurran.com.