This summer, in the face of record droughts and water shortages, communities from the Gulf Coast to Sonoma Valley are imposing unprecedented restrictions, and even outright bans, on lawn watering. They’re also stepping up enforcement — raising fines, sending out patrols, staffing hotlines and even shutting off service to repeat offenders. But to the most committed grass lovers, these restrictions have become a test of ingenuity. Some are creating personal reserves by digging wells or installing rainwater tanks. Others are pumping from backyard streams or using reclaimed sewer water that must be kept away from children.