DPW Offers Public Open House Tours of Pease and Peirce Island Wastewater Treatment Facilities to Celebrate Clean Water Week in April 2026

Clean Water Week in New Hampshire takes place April 12-18, 2026. The City of Portsmouth Department of Public Works is honoring the event by hosting an open house with guided public tours of both of the City’s wastewater treatment facilities. The Pease Wastewater Treatment Facility Open House is scheduled for Thursday, April 16, 2026 from 2 to 5:30 pm and the Peirce Island Wastewater Treatment Facility Open House is scheduled for Friday, April 17, 2026 from 2 to 5:30 pm. City staff will guide visitors through the two facilities and answer questions about the City’s wastewater treatment process. 

The upgraded Peirce Island Wastewater Treatment Facility opened in July 2021 and now provides a significantly higher level of treatment, resulting in cleaner effluent discharged into the Piscataqua River. The $93 million project was the largest capital project in the City’s history and the largest ever financed through the New Hampshire State Revolving Fund loan program, which supports water quality and public health through low-cost financing. In recognition of these improvements, the facility was named the New Hampshire Department of Environmental Services Plant of the Year in 2023. Additional upgrades to the facility will continue in phases in the coming years. The proposed FY27 budget includes funding to begin necessary upgrades to the Pease Wastewater Treatment Facility. A new headworks building was completed in 2020 to incorporate wastewater screening, grit removal, and raw wastewater pumping. The next phases include wastewater treatment process improvements and potential modifications to accommodate additional capacity for wastewater customers at the Pease International Tradeport. 

Since these are working treatment facilities, the open house tours are 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. 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.

At Peirce Island, visitors should park in the parking lot closest to the Wastewater Treatment Facility gate. At Pease, there is free parking adjacent to the facility building at 135 Corporate Drive. 

Questions concerning these open houses can be directed to Erich Fiedler, City Engineer at esfiedler@portsmouthnh.gov. There are no rain dates for these events. For more information, please visit the facility pages on the City’s website: Peirce Island portsnh.co/peircewwtf and Pease portsnh.com/peasewwtf.