The Department of Public Works announced last Monday that the town has shifted to Level 3 water restrictions. Under those rules, which will remain in effect until further notice, the watering of lawns and gardens with sprinklers or irrigation systems is only permitted from 7 p.m. to 8 a.m. on Tuesdays, Thursdays, and Saturdays. Watering done with hand-held hoses and cans is allowed any time, as is car washing. The change to Level 3, which often occurs at this time of year, was triggered under state water regulations when water flow on the Ipswich River dropped below a specified level. The two wells and two reservoirs that Danvers uses for its water supply — the system also serves Middleton — are located in the vicinity of the river. The town since May 1 had been under Level 2, under which outdoor watering with sprinklers or irrigation systems is allowed any day from 7 p.m. to 8 a.m. Prior to May 1, the town was under Level 1, in which there are no water restrictions.