DPW Tour of Peirce Island Wastewater Treatment Facility

The City of Portsmouth Department of Public Works hosted an open house with guided public tours of the Peirce Island Wastewater Facility (WWTF) and Road Resiliency Project on Saturday, May 31, 2025. City staff guided visitors through the facility and answered questions about the City’s wastewater treatment process and the raising of Peirce Island Road.

The upgraded Peirce Island Wastewater Treatment Facility opened in July 2021. Due to these upgrades, the facility now provides a significantly increased level of wastewater treatment that results in improved effluent discharge to the Piscataqua River. (Go to Fact Sheet.) The $93 million project was the largest in the City’s history and the largest in the history of the NH State Revolving Fund loan program that supports water quality and public health through low-cost financial assistance. Peirce Island Wastewater Treatment Facility was named NH Department of Environmental Services Plant of the Year in 2023.

Visitors also learned about the recently completed Peirce Island Road Resiliency Project which raised a 400-foot-long section of Peirce Island Road and the adjacent parking area to protect against predicted sea level rise. 

Questions concerning the open house can be directed to Erich Fiedler, City Engineer at esfiedler@portsmouthnh.gov. There is no rain date for this event. For more information, please visit the facility page on the City website: portsnh.co/peircewwtf.