NHDOT I-93 Corridor Widening Project | Exits 1 – 5

TFMoran engineers have been preparing Stormwater Pollution Prevention Plans (SWPPP), performing stormwater turbidity monitoring and inspection services for this multi-phase NHDOT interstate highway project since 2009. The project stretches 20 miles, adding two travel lanes in each direction from the Massachusetts state line through Salem, Windham, Derry, and Londonderry to the junction of 293 in Manchester, covering Exits 1 through 5. In addition to the widening, the largest NHDOT project to date includes improvements to each exit interchange, replacing or rehabilitating 43 bridges, building and expanding new park and ride facilities, and adding space within the median to accommodate a future commuter rail. These improvements will address the issues of safety; capacity/congestion and condition of aging infrastructure. According to the NHDOT website, traffic volumes have increased by over 600% since I-93 was built in the early 1960’s. Completion of this major infrastructure project is projected for the year 2022.

TFMoran Certified Professionals in Erosion Sediment Control (CPESC), Certified Erosion and Sediment Stormwater Inspectors (CESSWI) and Environmental Scientists have teamed with the various highway construction companies to perform stormwater turbidity monitoring to assure that stormwater outflows comply with the strict turbidity limits imposed by the NHDES to protect the adjacent water resources. TFMoran is part of the team meeting on a weekly basis with NHDOT and NHDES project officials. The team of highway builders have included R.S. Audley, Weaver Brothers Construction, George R. Cairns & Sons, Severino Trucking Co., Alvin J. Coleman & Sons, and E.D. Swett.

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  • Services: Stormwater Monitoring & Inspections