City Starts Work on Peirce Island Road Resiliency Project on April 15, 2024

April 10, 2024

In September 2023, the City of Portsmouth was notified that it had received $965,333 in Congressionally Directed Spending from the Federal Pre-Disaster Mitigation Grant Program through the NH Department of Homeland Security and Emergency Management for the Peirce Island Road Resiliency Project. Work on the project is scheduled to start the week of April 15, 2024 and is anticipated to be completed by mid-June 2024.

The City applied for the grant to provide consistent access to the Peirce Island Wastewater Treatment Facility (WWTF). Peirce Island Road, the sole access to the critical infrastructure facility, currently floods during spring high tides and storm events. The project will raise a 400- foot-long section of the road and the adjacent parking area. The road will then lie approximately three feet above its current lowest point and elevated above the 100-year flood line to protect it against predicted sea level rise. The raised road will also offer greater protection to the force mains under the road that carry wastewater to the WWTF. Additionally, a portion of the packed gravel parking area will be replaced with grass pavers and vegetation to improve stormwater management.

The roadway is scheduled to be completed first, followed by the parking lot, to minimize traffic impacts to the WWTF. No parking will be allowed within the construction zone (see map) for the duration of the project. The Peirce Island Off Leash Dog Park will be restricted to on leash only during construction hours, Monday through Friday 7 am to 4:30 pm. Dog owners are encouraged to use the alternate facilities at the Park & Ride on Route 33 and the South Mill Pond Dog Park during construction. Flaggers will be in place as necessary to manage traffic flow. The trail will re-open at the end of each workday and the site will be safe for public access. The City will place a message board with details and restrictions near the parking lot of the Robert P. Sullivan Boat Launch at Peirce Island.

The City does not anticipate any impacts to the rocky shore, salt marsh or marsh elder. The City will comply with the conditions set forth in the NH Department of Environmental Services Wetlands Permit to minimize any potential impacts to nearby wetlands. The project will maintain the existing walking trail and vegetation north of the road. The placement of a narrow buffer of stone and upland plantings will protect the road from high water and wave action during storms.

For more information, visit the project webpage:

Map of Peirce Island work site