Giant reservoirs serve as savings accounts for California's major water distribution projects and they are brimming right now. They hold roughly 70 million acre-feet, or enough imported water to meet Southern California needs for up to 30 years. Yet the region has been reminded this winter that it is never more than two or three years away from the next water crisis.
Southern California has always existed on the threshold of drought. Most of the region is, after all, desert. But until now, the engineers and visionary developers could always find a new water supply to bring to Southern California to satisfy the next wave of growth.
That era is at an end. There are no more giant projects to be built and no bags of government money to build them, in any event. California has entered the age of intense water management. The state must make do pretty much with what it has now. That may mean living even closer to the edge of shortage as time goes on.
To meet that challenge, California must surmount a variety of legal, institutional and psychological barriers that are more formidable--and, at the same time, more subtle--than the physical difficulties that faced the engineers who built the grand dams and canal systems.
The work has begun in the state Legislature, in the courts and in the arena of public policy. But much more needs to be done, soon, particularly in the development of public policy and in altering Californians' traditional attitudes toward water. The first mutterings about drought because of this winter's lack of mountain snows should serve as a warning.
While this year's runoff will be below normal, there is no concern about serious water shortages in 1987 because of the abundant supplies held over from 1986. The water managers will merely draw on the reservoir storage to make up for this winter's natural lack of supply.
That is the way it was meant to be. Government has invested billions of dollars in water projects over the years, in effect to impose some rationality on nature. The record illustrates that averages and statistical norms mean little in the year-to-year struggle to meet water demands.
The runoff from the Feather River watershed into Lake Oroville, the key storage facility of the State Water Project, amounted to 2.4 million acre-feet last February alone. In February of the previous year, runoff was a little more than 200,000 acre-feet. A tenfold increase in one year is extraordinary, but very little about the weather in California is ordinary. For all the reservoir storage California enjoys, there is not enough to cushion the state against consecutive dry years.
Even the impressive figure of 70 million acre-feet currently in storage is vastly misleading. Only a fraction of that is available to Southern California for a variety of technical, legal and environmental reasons.
Current supply and demand figures can be deceptive, too. Water managers cannot think just in terms of normal water years and normal demand. They must plan for dry years when water is short and demand is high. Then they must ponder how to allocate shortages if dry years come back-to-back, as in 1976 and 1977.
Steps are being taken. The Los Angeles Department of Water and Power initiated a cloud-seeding program over the Sierra Nevada this winter in an attempt to enhance snowfall and increase the spring runoff into the city's Owens Valley system. Both the state Department of Water Resources and the Metropolitan Water District of Southern California have embarked on ambitious programs to store surplus water in underground aquifers for use during droughts. These ventures are not far enough along to be of much help in the next two or three years, but could provide a significant hedge against drought in the future.
Metropolitan is pursuing a contract with the Imperial Irrigation District under which MWD would finance conservation measures, such as the lining of canals, in exchange for the rights to water saved. Ultimately, this could net MWD about 400,000 acre-feet a year, but that still would not even offset MWD's loss of Colorado River water to the new Central Arizona Project.
All of these actions, in fact, will do little more than maintain the status quo, while the MWD service area is expected to grow from 13 million in population to 18 million by the year 2000.
The real breakthroughs will come only when Californians are able to overcome outmoded concepts and myths about water needs and water supply. For instance:
--California is one state. Its water systems are so interrelated now that regions no longer can afford to battle over water. The north has used its political unity to stymie further exports to Southern California, but the shoe can be on the other foot. Both Oakland and San Francisco would like to expand their own Sierra-based water and power systems, but are finding they cannot do so without affecting other regions of the state. They may have to seek accommodation with competing interests before such projects can proceed.