DPW Offers Public Open House Tours of Peirce Island Wastewater Treatment Facility on May 31, 2025

The City of Portsmouth Department of Public Works is hosting an open house with guided public tours of the Peirce Island Wastewater Facility (WWTF) and Road Resiliency Project on Saturday, May 31, 2025 from 10 am to 1 pm. City staff will guide visitors through the facility and answer 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. 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 should park in the newly constructed Peirce Island parking lot closest to the Wastewater Treatment Facility gate where they will learn 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. 

Since this is a working treatment facility, the open house is limited to adults only. Attendees should wear sturdy walking shoes. Some of the facilities are located outdoors in rough, uneven and unpaved areas that are not accessible to those with mobility challenges. Restrooms are not available. If your mobility is limited and you will need assistance on the tour, please contact Lori-Ann Dixey at 603-766-1446 or ldixey@portsmouthnh.gov at least 48 hours in advance of the tour date so that accommodations can be made. Participants will be required to follow the prescribed tour route.

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.