University of South Florida Nets 2.3 Acres of New Land

On May 16th, 2013, the University of South Florida (USF) successfully installed Thirsty Duck’s ER-202 floating outlet and skimmer at its Tampa main campus. The floating outlet and skimmer was installed in a newly constructed, master planned, wet detention pond, which provides both water quality and flood control benefits for the East basin of the campus. By using the ER-202 to optimize the outlet hydraulics such that residence time in the pond’s permanent wet pool was maximized, the university was able to improve the system capacity to convert 2.3 acres of green space into directly connected impervious area (DCIA) from within the basin. Since expansion of the campus is limited due to the presence of four major thoroughfares around its perimeter, the conversion of green space to DCIA is an economic windfall for the university as it struggles to provide new facilities to accommodate its rapidly growing student population.

The project’s success depended on compliance with a recently adopted nutrient TMDL for Cypress Creek, an Outstanding Florida Waterway. “Meeting the TMDL criteria proved to be very challenging,” said Raymond Bellas, an engineer with Thirsty Duck. “The trick was to raise the outlet level from the permanent pool as high as possible while still maintaining the peak stage below the top of bank. It’s really tough to meet the nitrogen removal standard when using wet detention in Florida.” said Bellas.

The ER 202 was installed in an FDOT Type C precast concrete inlet and produces a constant discharge rate of 5.7 cfs over a total rise of 2.5 ft above its rim. The total installation time was less than two hours.

The project was designed by Tampa’s Ash Group Inc. and constructed by the Williams Co. from West Palm Beach, Fla., along with technical and permitting assistance provided by engineers from Thirsty Duck LP.

Source: Thirsty Duck LP