WATER IS NOT the only thing that has been off-again, on-again in the Maryland suburbs since Wednesday. Offices have been closed, then opened - or opened, then closed. Cutbacks in water use have been requested, then required, and then eased but encouraged. News reports have been conflicting; so have official comments. It's no wonder many citizens have been very confused and water use has fluctuated wildly as the crisis has steamed along.

A lot of this flows from the fact that the breakdown at the Washington Suburban Sanitary Commission's pumping plant was not only unexpected but unprecedented. WSSC and county officials were no more prepared for a water emergency than Virginia officials were for the natural-gas shortage that hit that state last winter. Suburban federal agencies were caught flatfooted, too; they know what to do in case of a blizzard or blackout, but have not coped with a water crisis before.

Well, everyone ought to get organized. Water use in Montgomery and Prince George's counties is going to have to be held down, perhaps for weeks, until full service can be restored. Beyond that, if the drought burns on and the Potomac continues to drop, water-saving on a sustained basis will be required in most, if not all, of the metropolitan area. Voluntary conservation is, of course, more desirable than mandatory curbs - but households, businesses and agencies are far more likely to cooperate if they understand just what officials would like them to do and if the rules don't change too often. Families can get used to set hours or days for lawn-watering, for instance - but they're not going to develop new habits if sprinkling restrictions come and go with the clouds.

Along the same lines, people should not wait for government to demand frugality. At federal facilities managed by the General Services Administration, all water-using equipment has been inventoried and priorities for conservation have been set. Every other public and private water-user ought to take the same type of inventory and decide where to start when cutbacks are the order of the day. For anyone who doesn't know about the importance of fixing drippy faucets or the value of water-saving devices on showerheads and in toilet tanks, a lot of information is available from WSSC and other local water agencies. Good tips can be gained, too, from California and other areas where tight water restrictions are in force. Out West, for instance, people routinely collect any rainwater that comes along, dump used dishwater and bathwater in gardens, and put buckets in showers to catch the extra spray. The general idea is to get as much use out of each drop as possible before letting it go down the drain.