Major water restrictions are about to take effect in areas ranging from Rancho Cucamonga to Thousand Oaks, and Baldwin Park to North Hollywood. But many nearby areas will escape the mandatory one-day-a-week watering limits — among them Santa Monica, Long Beach, Torrance and Beverly Hills. Why? The Metropolitan Water District of Southern California has targeted these first-ever water restrictions for areas that rely heavily or entirely on the State Water Project — a Northern California water supply that officials say faces a real risk of running dry. Areas that receive water from the Colorado River and other sources will be spared — at least for now.