Mashantucket Pequot Tribal Nation

Lantern Hill Dam Roadway Reconstruction & Improvements

North Stonington & Ledyard, CT

Benesch provided consulting services to the Mashantucket Pequot Tribal Nation to secure federal funding for the repair and replacement of Lantern Hill Road over Lantern Hill Brook and the dam. The roadway and dam incurred serious erosion and damage during the March 2010 storm, requiring emergency response support to stabilize the area, define remedial solutions, and assist in securing of federal funding for the project.
Benesch performed a hydrologic and hydraulic analysis of the dam and downstream culverts. The earthen embankment was repaired with a new spillway and outlet structure. The stream channel was stabilized. Existing town road culverts were replaced with new, clear-span structures. Approximately 900 LF of Lantern Hill Road was reconstructed.

The roadway reconstruction and bridge replacement were completed over a one-month period during the summer to allow for a detour, which would not impact school bus routes. Precast concrete foundations, a three-sided rigid frame, and retaining walls were used to expedite construction.

Benesch coordinated with Connecticut Department of Energy and Environmental Protection (CT-DEEP) – Dam Safety & Fisheries, the US Army Corps of Engineers, and Local Wetland Agencies to secure necessary environmental permits. The project was funded by the Federal Highway Administration and the Bureau of Indian Affairs.

Project highlights

  • Coordination with Town of Ledyard Department of Public Works
  • Consulting Services to Obtain Federal Funding
  • Hydrologic and Hydraulic Analysis
  • Roadway Replacement
  • Spillway and Earthen Embankment Repair
  • Environmental Permitting
  • Coordination with CT-DEEP, Army Corps of Engineers, Local Wetland Agencies