Challenge

When Con Edison Development began working with its affiliate, Newington Energy, LLC, in October 2000 to design a new 525-megawatt gas- and oil-fired combined cycle power plant in Newington, New Hampshire, the company wanted to make sure the cooling intake structure for the new plant met Best Technology Available (BTA) requirements.  Meeting these requirements would ensure compliance with future U.S. Environmental Protection Agency (EPA) regulations.

Solution

The Envirex^® Modified Ristroph fish screen safely removes fish from intake systems.  Designed specifically for environmentally sensitive conditions, the screen has been approved as BTA in several states.  The Smooth-tex^® flat wire screen surfaces minimize fish injury, and slots sized to the nearest 0.04-inch exclude even very small fish.

Results

In May 2001, Siemens Water Technologies provided the Newington plant with Modified Ristroph fish screens, grab-style trash rakes, stop logs, wash water pumps and bar racks. 

Marine Resources, Inc. conducted fish impingement studies at the Newington site from October 2002 to January 2004, and reported the findings to the EPA.  Thirteen species with an extrapolated annual total of 324 fish were represented in the samples collected.  An analysis of the high and low-pressure return system showed that the low-pressure screening system recovered 85 percent of all fish impinged.