Clinton Storage Facility

Project Description:

In January 2008, Onondaga County Executive Joanie Mahoney halted the construction of a sewage treatment facility in Armory Square. As an alternative, the County is now building this state-of-the-art, six and a half million gallon stormwater storage facility and simultaneously investing millions of dollars in green infrastructure throughout the City of Syracuse to capture stormwater before it enters our sewer system.

Facility Details: The Clinton CSO Storage Facility Project is a 6.5 million gallon combined sewer overflow storage facility constructed under the parking area between the elevated rail tracks and Onondaga Creek just south of the Armory Square area of downtown Syracuse (known as the Trolley Lot). During wet weather events, the facility’s three, parallel 18-foot diameter, underground storage tunnels capture flow from 9 combined sewer overflows (CSOs) in the vicinity of the Trolley Lot. The wastewater is stored in the tunnels until it can be conveyed via the main interceptor sewer to the Syracuse Metropolitan Sewage Treatment Plant (Metro) for treatment. The off-site conveyance piping, which will transmit the flow to the facility, was installed under the Clinton CSO Phase 1 and 2A conveyances projects completed in 2009. There is additional on-site conveyance piping installed under this project to connect the existing sewers to the new facility. In addition to the tunnels, there are two above-ground structures located at either end (east and west) of the parking lot, which provide access to the tunnels and house the pumping, grit collection and odor control facilities.

Greening the Gray: To further enhance the sustainability of the facility, the project included green infrastructure components. The stormwater runoff from the entire site that measures approximately 275,000 square feet (SF) or 6.3 acres is managed by green infrastructure. The stormwater from the area surrounding the main structure on the western half of the site is collected by a series of catch basins and stormwater piping that will outfall into two bioretention basins. The bioretention basins allow the stormwater to infiltrate into the ground rather than immediately runoff to the creek. In addition, stormwater runoff from the eastern half of the project site, which was restored as a parking area, is directed to a subsurface collection facility and used to flush the storage tank to clear them of grit and debris that may have settled or been left behind after the stored combined sewage was transmitted to Metro.

Operation of the Facility: The Clinton CSO Storage Facility was placed on line on December 27, 2013. The first large event occurred on March 29, 2014 with nearly 2” of rainfall in the City of Syracuse as well as significant snow melt. The snowpack was concentrated with water due to the very wet late season snow storms. The Clinton Storage Facility functioned essentially as designed with the effluent pumps activating when the tank reached a preset level. The Trolley Lot parking area was restored in 2014 and will be the location for the 2016 Save the Rain Clean Water Fair on September 10, 2016!

Presentation to the Onondaga County Legislature – December 2013 (PDF)