Merrimack Valley, Mass.

Gas explosions: A series of explosions and fires stemming from gas leaks last week left one person dead, injured more than 20, and forced the evacuation of 8,600 homes and businesses. Forty-eight miles of pipe will need to be replaced. The precise cause of the blasts in the three towns north of Boston—Lawrence, Andover, and North Andover—is under investigation, though federal regulators found that natural gas from Columbia Gas of Massachusetts was flowing through pipes at 12 times the normal rate. Lawrence Mayor Dan Rivera called the company “the least informed and the last to act” as the chaos unfolded. The area’s representative in Congress, Democrat Seth Moulton, charged that the gas company took five hours to let anyone know there was even a problem. Residents waited for inspectors to move through houses one by one as electricity got cut off and smoke filled the skies.