Stream Daylighting and Floodplain Creation

Petty's Run

Pettys Run Stream DaylightingPrinceton Hydro was retained by the City of Trenton to restore a stream as part of a larger urban revitalization and brownfield redevelopment project. The city has taken ownership of the former Magic Marker factory site and other properties adjacent to the stream to build affordable housing and create urban greenspace. The stream, Petty’s Run, suffered a variety of common urban afflictions including a narrow road crossing that routinely flooded, 250 feet of channel piped underground, contaminated soils on both sides, and heavy debris and litter throughout the channel.

Princeton Hydro developed a “green-infrastructure” design that addressed a range of issues including the restoration of many of the natural functions associated with this stream. Heavy debris and the concrete remains of earlier development were removed from the channel. The upstream road crossing was removed and replaced with a pedestrian crossing. Channel dimensions were designed to accommodate higher flows. In addition, the downstream 250-foot piped section was daylighted and a small adjacent floodplain meadow was created. At the downstream end of the project, a new headwall and larger pipe were constructed to connect to the existing downstream drainage network. While adding habitat value, the area serves as aesthetic public open space with a walking trail linked to the nearby neighborhood.

The stream was redirected from contaminated areas and failing banks were stabilized using a variety of bioengineering techniques. In the daylighted reach, a series of pool-riffle features using riverstone were installed to allow for the necessary changes in elevation. Princeton Hydro worked with NJDEP and the City of Trenton to finalize the design and acquire the required permits. This project was completed in the Summer of 2011.

The project won a 2011 Phoenix Award for Brownfield Redevelopment and a 2013 Bowman’s Hill Land Ethics Award.