Storm Water Systems Installed at Work Trade Center Transportation Hub

Work continues on the World Trade Center Transportation Hub (HUB) and the Terre Kleen storm water treatment and recycling structures (WQS) are in place, capturing and recycling storm water runoff.  Set to open in 2015, design work on the Hub was started in 2005 by the Downtown Design Partnership (DDP). As a result of a rigorous design process, Terre Hill Stormwater Systems (THSS) worked closely with the DDP to design and manufacture a highly efficient, compact treatment unit that captures pollutants such as hydrocarbons, grease, floatable trash and debris as well as sediment. The final design was a specially designed Terre Kleen inclined plate hydrodynamic separator. The stacked inclined plate sedimentation technology used by Terre Kleen enabled THSS to meet to continually shrinking dimensions imposed upon the water quality treatment devices. As part of a treatment train design, the goal was to create sufficient sedimentation surface area to remove sediment and to capture trash, debris and hydrocarbons before the storm water enters a filtration device to prepare it for recycling onsite.

"The key to this project was to design and manufacture WQS that would fit within a 4 ft vertical space located between the roof slab of the top underground floor and the surface of the pedestrian plaza at grade level; be watertight and have performance capabilities to remove sediment, trash, debris and hydrocarbons to meet NPDES requirements," said Dale Groff director of Terre Hill Stormwater Systems.. 

The World Trade Center Transportation Hub project was not a typical storm water treatment and recycling design. Below the pedestrian plaza there is a five-level complex of mass transit facilities, retail stores and pedestrian walkways. THSS was charged with developing a WQS that could receive and treat 1,750 gal per minute of storm water while remaining waterproof. The project specifications called for the design, manufacture and delivery of two AASHTO HS-20 load rated precast concrete hydrodynamic separators for pre-treatment of storm water for reuse. Each structure was required to be waterproofed with an AGRU Sure Grip high-density polyethylene liner cast on the interior surfaces of the structure. Each structure contained 158 sq ft of sedimentation surface area within an interior area of 82 sq ft.  Water quality treatment flows were specified at 3.84 cfs (1,724 gpm) and 3.9 cfs (1,750 gpm) with no loss of capture pollutants. 

Source: Terre Hill