Managing stormwater with Greenstreets

Two weeks ago we first ran a story about Curbolution, Team Sang-ayuna's submission to the Minds in the Gutter search for stormwater capture technologies.  Today we follow-up with a profile of the City's Greenstreets Program.

What: Greenstreets for stormwater capture

Furmanville Ave, 80th St and Dry Harbor Rd, Queens

Who: New York Parks and Recreation Department in partnership with the Department of Transportation.  DOT owns the roadways -- roadways are used because they offer greater storage capacity than sidewalks -- and Parks provides design services, designation, maintenance, and assumes liability.

Inlet (Furmanville Ave)

How: Greenstreets for runoff mitigation differ from the City's conventional greenstreets in their physical design and location.  While both types of Greenstreets are landscaped with trees, shrubs, and herbaceous perennials, the stormwater ones are located in flooding hotspots and in neighborhoods adjacent to areas with "troubled" water quality.  Stormwater Greenstreets are designed to meet a performance standard of 1.7 inches of rain.  This is accomplished with elements such as inlets and outlets (curb cuts), bioswales, and layered engineered soil profiles (two feet of soil, geotextile, and one foot of bluestone) to capture, store, and infiltrate stormwater.  Future design elements will include concrete weirs with gravel for sediment filtration.

In May of this year, I went on a tour of Greenstreets with Adriana Jacykewycz and Nandan Shetty of NYC Parks (thank you!). The stormwater-capture Greenstreet at Furmanville Ave in Queens was an early project and was completed in 2007. It is composed of a "bumpout with curb cut inlet, deep excavation, bioswale, and crushed bluestone reservoir; soil moisture sensors have been installed as part of a rainwater and evaporation monitoring collaborative of Drexel University, NYC Soil and Water Conservation District, and Atlas Scientific and funded by NYS DEC and NYS DOS.  The Church Ave Greenstreet in Brooklyn was completed in the spring of 2009 and is a triangular space with a "curb cut inlet, deep excavation, bioswale, and crushed bluestone reservoir."

Outlet and bioswale at Church Ave, 14th Ave and 35 St, Brooklyn

Under the 2007 PlaNYC initiative, the Greenstreets Program was charged to develop a total of 800 new greenstreets  All Greenstreets will contribute to the City's goal of a 30% reduction in "global warming emissions."  The program received $2 million in federal stimulus money (ARRA) to construct 26 new stormwater greenstreets in the next two years.

We missed Adriana Jacykewycz  webinar about Greenstreets via the Urban Natural Resources Institute.