BY KATHIE NORTHRUP

The New Hampshire Division of Historical Resources has recognized Hooksett’s Lilac Bridge as an important state resource and approved its listing to the State Register of Historic Places on April 28.

Designed by John W. Storrs, New Hampshire’s only specialist in bridge design during the early 20th century, it is the state’s only surviving example of a threespan High Pratt truss bridge.

Prior to 1805, travelers and residents used a ferry to cross the Merrimack River in the Hooksett village area.

The Londonderry Turnpike, which ran from Concord to the Massachussets state line, brought travelers and large quantities of goods through the village. The turnpike was privately funded by the Londonderry Turnpike Corporation, which charged tolls along the route.

In 1805 an act of the Legislature allowed the erection of a toll bridge at “Islehookset Falls,” where the turnpike crossed the Merrimack River. The corporation erected the first bridge in 1805, and it immediately put the ferry out of business. The corporation sold the bridge in 1853 to the town of Hooksett (incorporated in 1822) for $1,640, and toll charges were removed.

On Sept. 20, 1857, the old turnpike bridge burned, was rebuilt and was destroyed again in a flood two years later. The third bridge on the site was a three-span wood truss bridge completed in 1859. In 1908, town fathers questioned its safety. They hired John Williams Storrs, a bridge designer/engineer, to prepare a condition assessment.

In July 1908, he reported: “The bridge has been over strained and computations show it to be structurally weak. I would advise immediately that you limit the loads to the lightest possible. Have automobiles go slow, and horses walk.”

In 1909, voters authorized the construction of a new steel highway bridge at a cost not to exceed $26,000. The bridge opened for traffic in early November 1909. A newspaper article reported that the “citizens of Hooksett are to be congratulated upon having one of the best and most thoroughly constructed up-to-date bridges in this part of the country.”

In the flood of March 1936, a three-span wooden railroad bridge upstream of the highway bridge was swept away. One portion knocked out the southern span of the steel bridge. Remnants of the steel span lodged in the river downstream. When the river is low, one can still see those remnants today.

For about a month, Hooksett residents could not cross the Merrimack without traveling to Concord or Manchester.

By April, a footbridge along the B&M trestle was constructed for use by pedestrians. The southern span of the steel bridge was rebuilt by Works Progress Administration workers by Sept. 15, 1936, and the bridge opened once again to traffic.

The bridge served Hooksett well until the late 1960s, when safety concerns began to surface.

In December 1969, the weight limit was reduced because of a weakness found when the bridge was being repaired. At the 1972 Town Meeting, funds for the town’s share of a new bridge were requested. The new Memorial Bridge opened on July 27, 1976. The steel bridge ended its first phase of service to the town. In the 1990s a proposal to dismantle the bridge was defeated and plans to rehabilitate it were ultimately abandoned.

The Town Council renamed it The Lilac Bridge in 1997 at the suggestion of Grace Pomeroy, then president of the Hooksett Historical Society. It is eligible for the National Register of Historic Places and in 2000 was designated an Official Project of Save America’s Treasures.

Kathie Northrup, chairman of the Hooksett Heritage Commission, completed the research and prepared the inventory form/application.

Listing of the Lilac Bridge, along with other sites, will be acknowledged at a ceremony to be held at the Robie’s end of the bridge at noon on Hooksett Heritage Day, Saturday, May 17.