California Drought - A Millennium Perspective

A millennium perspective on the California drought Ken Johnson, Stantec California, is a state with the population and economic power of an independent nation, with the 10th largest economy in the world, and a 3 million more people than in Canada.

The economy is massive with Silicon Valley, Hollywood and millions of acres of farmland, however, this wonderland of glamour, technology and climate that has been developed over the past 165 years (more or less) in a semi arid region, which has clearly demonstrated the propensity for drought.

Photo caption: Large engineered solutions to water in California started with such projects at the Los Angeles aqueduct, which started flowing in 1913.

The current drought should therefore not come as a surprise because according to the recent history, there have been drought conditions in the 1920's, the 30's, the 40's, the 70's, the 80's and the 90's. The 1987 to 1992 drought lasted six years, when statewide reservoir storage hovered around 60 percent. The worst drought was in 1976 - 77, when low rainfall sent the state scrambling, and runoff was just 20 percent of normal.

The modern history of California droughts is nothing compared to the last millennium. Through studies of tree rings, sediment and other natural evidence, researchers have documented multiple droughts that lasted 10 or 20 years in a row. There are also two severe mega droughts that make the Dust Bowl of the 1930’s look tame. The first was a 240-year-long drought that started in 850, and 50 years after that another mega drought that stretched at least 180 years (1140 to 1320).

Based upon this history it is probably fair to say that, sadly, California is paying the price for gross water under management over the past century and a half.

The cast of characters to this under management is many, including farmers who have contributed to because of poor irrigation practices such as the waterwasting open trenches. Homeowners have contributed to the shortage because many of their houses lack water meters, and the yards have with lush lawns and big pools. Engineers and planners have contributed to the shortage because of lack of a foresight in spite of the overwhelming evidence on the full scope of the problem.

However, the ultimate responsibility belongs to the California politicians for maintaining a short term perspective on a long term problem.

The current measures to meet the state governor’s executive order for a 25 percent statewide reduction in urban water use may be too little too late. A prominent and very smart hydrologist with NASA , who has been monitoring the decline of the total water storage (surface water and ground) in California since 2002, when satellite based monitoring began, has noted that a steady decline is happening.

Photo caption: A large residential “oasis” near Palm Springs containing numerous golf courses, is contrasted to the dry and barren natural landscape next door.

This individual has tried to make a case to anyone who will listen, and his rather blunt conclusion, was that "we're screwed." These harsh words were offered as part of a commentary on a very good documentary entitled “Last Call at the Oasis.”

Of course given the immense scale of the resources that can come to bear from the State of California and the United States of America, California will probably continue to flourish, however, there is a new chapter that is just beginning. How it will unfold will be interesting, but water use and water management in the Golden State are probably going to change forever.

One of the numerous practices in California that is just plain silly is that water meters have still not been installed in each and every household. Although water meters have in use in California for 70 years, there are still approximately 250,000 households lacking meters.

An average water use in the state (not including agriculture) of 740 litres per capita per day (l/c/d) (200 gallons per capita per day) does not come as a surprise.

However, Palm Springs is “over the top” with water use at 2800 l/c/d (740 g/c/d) to satisfy all the 125 golf courses. The lowest reported water use of 290 l/c/d (76 g/c/d) is in the Westborough Water District of South San Francisco.

With the surface water crisis, groundwater pumping is increasing exponentially, and there are growing concerns that this virtually unregulated draining of California’s underground aquifers could have major consequences within the next couple of years. It is estimated that California's aquifers could be completely depleted in 60 years, and wells are already starting to run dry. In some areas of the large Central Valley agricultural region, which is east of San Francisco, the land is sinking by 30 centimetres or more per year.

Some of the current thinking is that the state should build dozens of desalination plants, construct new pipelines from the north, which would cost billions of dollars. In fact, there are a number of existing desalination plants around the state that were under construction during the previous droughts, and were subsequently mothballed.

However, these potential solutions are applying the dominant "engineering" thinking of the past.

California water law was built around preserving the water rights of those who staked claims to waterways more than a century ago, or have property that abuts the rivers and streams. Thousands of people, water districts and entities with claims dating before 1914 have long enjoyed nearly guaranteed access to water.

Modern thinking about water shortages looks at the problem from a water shed management perspective, with engagement of the full landscape (surface and subsurface) for improvements. This approach makes use of the "natural infrastructure" and applies action such as positive incentives for agricultural producers to implement better land use practices. To date the action by the State of California has had limited action associated with the watershed approach, resorting to mandatory cutbacks by individuals on water use, which are ultimately only a "drop in the bucket" to a solution.