Brockton said its decision to buy rather than lease 7,734 street lights from National Grid will save the city $649,656 in the first year. Residents will report outages by calling the Highway Department at 508-580-7810 between 8:30 a.m. and 4:30 p.m. on Monday through Friday, Mayor Linda Balzotti said. Nonfunctioning street lights can also be reported by sending an e-mail to dpw@cobma.us, she said. The reports should describe the problem, include the pole number, and the street address closest to it, along with a name and phone number in case the city worker has questions.