1-93 Transportation Improvement Project

Project corridor in southern New Hampshire.

Independent Archaeological Consulting (IAC) conducted multiple phases of archaeological survey for the proposed widening of the Interstate 93 from the Massachusetts border at Salem, New Hampshire, through Windham, Derry, Londonderry and into Manchester – a distance of about 20 miles. The 20-mile-long widening project for the most part follows the existing corridor but proposed to widen lanes, reconstruct exits, and expand the ROW, with the possibility of impacting archaeological sites.

For the Phase I effort, IAC re-examined 37 Euroamerican sites along the I-93 corridor and recorded a total of 247 additional cultural features such as farmsteads, house cellarholes, barn foundations, wells, and stone walls, abandoned roadbeds, railroads, and trolley lines. From this long list, IAC subjected nine 19th-century historic sites to a Phase II Determination of Eligibility (DOE) study. Altogether, IAC excavated 233 shovel test pits, eight 1-m-x-1-m test units, and nine backhoe trenches, collecting 18,082 artifacts in the process. Among the nine sites investigated, only two are recommended as eligible for the National Register of Historic Places. The remaining seven were found to have been truncated or disturbed during the initial 1960s construction of the interstate and therefore had poor integrity.

Constructed in 1961 as part of a major Federal Highway Interstate program, the highway cut through a rural landscape that had been farmed by Euroamerican settlers as early as the 1720s. Increasingly through the nineteenth century, commercial centers and villages of varying sizes emerged in each of these towns and cities. Farmsteads and other rural features remained scattered on the periphery of these economic centers. Eventually, rural transportation systems – such as Old County Road and, by the mid-nineteenth century, the railroad – linked individual and regional farms to larger and more distant markets. Archaeological research questions considered the effect of the interstate highway on these previously-existing transportation systems.

In the 19th century, Old County Road linked at least four farmsteads studied at the Phase II level, and also connected two others whose physical traces were too obliterated by the I-93 corridor to study beyond the Phase IB. Many of these were associated with the long-standing Dinsmore family, whose progenitor, John “Daddy” Dinsmore, had arrived from Ireland in 1723. Beginning at its southern end, Old County Road connected three Dinsmore dwellings – those of John Dinsmore, William Dinsmore and the unmarried Dinsmore sisters

Of the nine sites investigated at the Phase II level, four can be described as farmsteads; i.e., domiciles supported primarily through agriculture on land owned by the resident farmer. These sites typically comprise of a dwelling and at least one barn and perhaps one or several outbuildings. Three other sites can be defined simply as homesteads, whereby residents lived in dwellings but obtained their primary source of income off-site and through other than agricultural means. The Misses Dinsmore homestead is one such site, although it may also be said that their neighbor and brother, William, partially supported the women through his farming. The remaining three sites consist of the remains of the 18th-century Corning Mill and the Boyer Lane Granite Quarry.