The New Jersey Department of Transportation recently embarked on a road improvement project to streamline traffic flow along the busy Route 73 corridor. Route 73 is a major artery connecting southern New Jersey and Philadelphia via the Tacony Bridge over the Delaware River.
One particularly challenging aspect of this project is road drainage. Widening access ramps and bridges is counterproductive if road flooding brings traffic to a halt during every rain event. Southern New Jersey is flat, and is crisscrossed by a lacework of tidal streams. One of those streams is the Pennsauken Creek, which runs parallel to Route 73 with just a few feet of vertical separation between the normal water level and roadway. A generously sized drainage system successfully removes water from the highway during the initial part of a rainstorm, but eventually, streams and creeks become rain swollen. Water reverses direction, gushing from storm drains and flooding roadways to the point that they become impassable.
The solution was to install Onyx Duckbill check valves at drainpipe outlets. The valves discharge huge volumes of rainwater with virtually negligible head loss while reliably preventing reverse flow during high water events. Unlike flap gates, they are immune to jamming, freezing or choking on debris. The valves operate silently, and are immune to d