Maplewood Avenue Causeway over North Mill Pond Structural Repairs: This project includes repairs to the culvert and other safety upgrades. The Engineering team is currently working to gain approvals from the various regulatory agencies.
Update January 2023: Anticipated bid request for repairs to the sidewalks, guardrails and potentially lighting in summer 2023 for construction in fall 2023. Significant improvement to this bridge is identified as a priority for NH DOT funding, but the cost exceeds the NHDOT State Bridge Aid Program (that provides 80 percent funding) that is currently available.
This project is being completed as part of the City’s Bridge Capital Improvement Program. Evaluation was included in the 2018 Citywide Bridge Evaluation. This assessment determined that a rehabilitation of the arch with an adhered lining system would allow the City to extend the lifespan of the bridge without the cost of a full replacement. The work will include resurfacing of the roadway, resetting the curb and reconstruction of the sidewalks, but will not address the sea walls or utilities.
Extending the timeframe for full replacement has improved the City’s chance of obtaining the 80% NHDOT State Bridge Aid Program funds for this work. When the bridge is replaced, work will include the sea walls and reconstruction of the water, sewer, and aerial utilities.
The Department of Public Works directed geotechnical investigations of the Maplewood Avenue Bridge over the North Mill Pond in July and August 2020. This work included the following:
- Geophysical Survey using metal detectors, ground-penetrating radar, and precision locating equipment to identify underground utility infrastructure and other obstructions below the Maplewood Ave. Bridge over North Mill Pond bridge.
- Test borings using truck-mounted vacuum-excavation and drilling equipment to collect samples of the soil and bedrock below the bridge at six locations.
Start Date: Fall 2023
Funding Source: CIP FY24-29. Anticipated funding from bond.
Designer/Contractor: HTA Engineering