In 1985, the Town of Derry first approached NHDOT regarding the possibility of obtaining funding for a new I-93 Exit 4A Interchange. The Southern NH Regional Planning Commission (SNHPC) conducted a transportation study for Derry later that year to evaluate alternatives to relieve traffic congestion along NH Route 102 in downtown Derry. Based on the results of this study, the Derry Town Council endorsed a new interchange alternative.
In 1987, NHDOT and the Towns began cooperating to develop an acceptable design for a new exit to I-93 between existing Exits 4 and 5 to serve both towns. The Towns were notified that the project was required to meet current NHDOT highway design standards. At this time the Towns initiated preliminary planning and engineering.
In 1988, an application for approval of a break in the limited access right-of-way for a new interchange on I-93 between existing Exits 4 and 5 was submitted to NHDOT and FHWA. This proposal received preliminary approval from FHWA in 1991, subject to several conditions, including compliance with the National Environmental Policy Act (NEPA). FHWA later determined that an EIS must be completed for the project. Additionally, only easterly access from the interchange was approved.
The formal EIS process began in early 1998. FHWA published a NOI to prepare an EIS, and a formal public scoping meeting was held. Twenty-two meetings were later held soliciting input from federal, state, and town officials and the public. The meeting groups included the Citizens Advisory Technical Committee (CATF) and Technical Advisory Committee (TAC), which included town representatives, regional and state planners and engineers, and the public. A major purpose of the early public involvement was to obtain input on identifying a reasonable range of alternatives to consider for the Project.
The EIS study paused in 2003 because of additional scope requirements identified through the interagency coordination process. In June 2005, the Towns re-commenced the EIS review process and previously collected data was updated.
In March 2006, at a meeting with federal, state, and town officials, a comprehensive summary was presented and discussed that compared the advantages and disadvantages of the alternatives. The Towns subsequently selected as their Preferred Alternative (Alternative A), a new Exit 4A Interchange located approximately 1 mile north of Exit 4. Concurrence in the selection of the Preferred Alternative was received from the resource agencies. In July 2007, FHWA approved the DEIS and issued it for review (FHWA-NH-EIS-07-01-D). The DEIS issuance was followed by a Joint NHDOT, New Hampshire Department of Environmental Services (NHDES) and U.S. Army Corps of Engineers (USACE) Public Hearing held on September 12, 2007 at the Derry Municipal Center. On March 3, 2008 a Necessity Meeting was held at the Derry Municipal Center to update the Special Committee members on comments received at the September 12, 2007 public hearing and to review the Towns’ responses. At the conclusion of that meeting, the Special Committee voted unanimously to approve the Necessity of the Project.
From March 2008 through December 2010, work progressed on addressing comments received on the DEIS, including developing compensatory mitigation for Project impacts on wetlands/waters of the United States. These efforts were initially limited to collecting one year of stream monitoring for chlorides (including Shields Brook) and performing a vernal pool field study in spring 2009. In late fall 2009, full time work resumed on the FEIS. These efforts were largely focused on updating the traffic data and the impacts associated with each alternative. In 2011, the environmental clearance for the project was put on hold because of funding issues.
In October 2015, the Governor’s Office directed NHDOT to accelerate the I-93 Exit 4A Project, and the Project was subsequently incorporated in the state’s Ten Year Transportation Improvement Plan for 2017–2026. NHDOT and the Towns entered into an agreement under which NHDOT will provide administrative oversight for the completion of the environmental review process, then the Project will transition to NHDOT control during final design and construction.
From December 2015 through February 2016, the consulting team identified the updates and additional technical studies necessary to complete the review of the project under NEPA and other environmental requirements through eight meetings of the EIS Review Team (EISRT). As part of these meetings, the EISRT performed a comprehensive reevaluation of the Project that considered changes in (1) environmental regulatory requirements, (2) existing conditions, (3) expected future conditions, and (4) the design of the Project. In addition to the consulting team, the EISRT consisted of representation from the Towns, FHWA, and NHDOT.
Based on the updated technical studies identified by the EISRT, the Towns entered into a contract with the CLD Consulting Engineers team to prepare the remaining environmental documentation required for FHWA approval (an SDEIS and FEIS/ROD). Work on the SDEIS commenced in June 2016.