Rebuilding Antrim Road

By: Portland Cement Association

Much of the recognition for upgrading infrastructure in a sustainable and environmentally responsible way often goes to larger cities. However, the success of innovative road rebuilding techniques in the town of Hancock, N.H., with a population of 1,823, demonstrates that even the smallest of towns can save time, money and resources while minimizing environmental impact.

With an elevation change of almost 400 ft from the lowest point to highest point within the town’s road system and harsh New England winters wreaking havoc on roadways, Kurtis Grassett, director of public works, knows the challenges of keeping these roads safe and in good repair while working with limited resources.

Antrim Road, in particular, posed a problem. A 2,000-ft section of the road has seen three 100-year floods in three years—2005, 2006 and 2007. This road also has a serious groundwater problem, which has damaged the road base and complicated the rebuilding process.

“The challenge of limited resources and an abundance of springtime floods had the town of Hancock looking for rebuilding techniques that were long-lasting and cost effective. Kurt Grassett evaluated many alternatives to rebuilding this road and selected full-depth reclamation (FDR) with cement because it was the most cost-effective and reliable approach,” said Heather Steffek of the Road Recycling Council’s New England region.

Rebuilding Antrim Road using FDR with cement saved the town about $100,000 in 2006. Hancock taxpayers saw further financial and environmental benefits because the existing base and pavement materials, already paid for by the town in previous years, were recycled into the new stabilized base. This environmentally friendly process significantly reduced fuel consumption by reducing the need to ship in new materials. It also eliminated the need to dispose of the old pavement, saving precious landfill space.

The 2007 flood hit Antrim Road in April while there was still snow on the ground. The runoff was caught between the edge of the pavement and the snow bank, resulting in severe erosion. The velocity of the water dug a channel about 8 in. deep and 1 ft wide down the edge of the road.

“Without the cement-stabilized base, I know I would have lost the pavement and roadway. It acted as a barrier to the erosion that was occurring on the shoulder,” Grassett said.