A North County town is expected to get a $278,000 grant to make repairs to a broken water main suspended from a historic covered bridge across the Ammonoosuc River. The 100-year-old cast iron pipe suspended on the underbelly of the Northumberland Covered Bridge feeds wells and storage tanks. It broke in April, and only temporary fixes have been made. The New Hampshire Community Development Finance Authority approved an Emergency Community Development Block Grant for the repairs in Northumberland. The solution requires drilling to install 300-plus feet of new pipe beneath the riverbed. Engineers who've examined the water main say a leading cause of the damage comes from constant vibrations of snowmobiles, which use the 1852 covered bridge as a river crossing.