It has become almost cliche to say that water is the “next oil,”  but the big difference between oil and water is that, if we have to, we can live without oil. A recently released documentary, “Last Call at the Oasis,” makes a valiant effort to demonstrate why water, our most precious resource, is at serious risk.

Unfortunately, “Last Call at the Oasis” seemingly sank without a trace within a few weeks of its May 4th release, even though it had a significant media push and was produced by Participant Media, the same company responsible for  “Waiting for Superman,” “An Inconvenient Truth” and “Food Inc.” Perhaps the public’s lack of interest in water is a symptom of the great confidence people in California and in the United States have about the quality and supply of their water.  Certainly California and virtually everyone in the United States has for the past century been blessed to have a reliable and safe water supply. As “Last Call” notes, the overall water footprint of each American – taking into account direct uses such as drinking, flushing toilets and washing clothes, and indirect uses such as producing food that is eaten – is about 2,000 gallons of water per day, according to a 2011 paper in the Proceedings of the National Academy of Sciences. That compares to 900 gallons per day for residents of the United Kingdom, less than 800 gallons for people in China and just 2.5 gallons per day for the world’s poorest people.

However, even in California this reliability cannot be taken for granted as there are warning signs of serious trouble ahead. Maintaining a safe and reliable water supply is an engineering and technological challenge that comes with a significant price tag. “Last Call at the Oasis” shows scenes of people in India fighting for water jugs and African girls carrying water on their heads. While Californians are not at immediate risk of this, the documentary raises a number of important issues that we ignore at our peril.

“Last Call” focuses heavily on water supply. What is rarely talked about is that even if there is a sufficient supply there are significant legal hurdles and political barriers in California to efficiently allocate the water that we do have, specifically in the areas of water rights and infrastructure.

Mention the phrase “water rights” and most people’s eyes quickly begin to glaze over. At best people may connect it with the classic Jack Nicholson film “Chinatown” or Mark Twain’s well-known phrase that in California “Whiskey is for drinking; water is for fighting.” Very few people know that California’s water rights system is what governs the water flowing out of their tap, watering their lawn, producing the food they eat or filling their swimming pool.

So why should the average Californian care about water rights as long as water comes out of their tap? Because California’s water law is an obstacle to dealing with some of the issues the film discusses, and if those issues aren’t faced soon the day may come when water fails to emerge from our taps as safely and regularly as we are used to.

In “Last Call,” scientists and academics describe the issues California and the world face. Jay Famiglietti, a UC Irvine scientist specializing in water, particularly focuses on water use by agriculture, increasing urban needs and global climate change. The essential theme of his comments, and those of other commentators in the documentary, is that if Californians were smart, we would dramatically rethink agricultural and urban water use. The shortcoming of these analyses is that even if that rethinking were to occur, the state’s water rights system would need to undergo some significant changes. First, two of the fundamental principles of many California water rights are “use it or lose it” and “first in time, first in right.”  Use it or lose it means that if a person with water rights actually conserves the water and does not use it, he may be at risk of permanently losing his water right. That principle goes against the idea of conservation, a solution strongly advocated throughout the documentary. Some changes to water laws have been made to limit the risk of losing water rights when conserving, but the law is far from as clear as it needs to be for users to feel comfortable that they won’t lose their rights.

First in time, first in right means that people who used the water first have the first right to it.  In California widespread agriculture developed long before the state’s massive population growth, which means that many farming uses have a higher priority to water than cities. Furthermore, agriculture generally has a higher priority to tap into groundwater than most cities.

Putting aside for a moment the importance of growing food and the great significance of agriculture to California’s economy, assume that Californians “rethink” the distribution of water between agricultural and urban uses. As you can see from these water law rules, with a few exceptions, either the law would have to be changed (which would be highly disruptive to say the least) or farmers would have to be compensated for their water rights. The latter option, widely known as “water transfers,” is much more developed in places such as Colorado and Arizona. Thus, this would be another area where California’s long-held water rights laws would need to be addressed.

Turning from the law, new water infrastructure is a very pressing issue that California must face. If we don’t deal with this soon, our safe and reliable water will be seriously at risk.

Much of the water that grows crops in the Central Valley and serves Southern California homes comes from Northern California. Without this supply both areas as we know them would cease to exist. This snow-fed water, which trickles down from the mountains, is captured in large lakes in Northern California and moved through the Sacramento-San Joaquin Bay Delta via aqueducts to areas south. The infrastructure moving this water through the Bay Delta is in serious need of improvements and the “Delta fix” will be very expensive. Estimates range from $15 billion to $60 billion.

“Last Call”  also stresses the potential of water efficiency (through retrofitting both houses and agricultural systems) and water reuse (capturing storm water runoff and treating more wastewater so that it is available for higher quality uses such as drinking water).  Singapore has been a leader in reuse and the technology exists to do this. Lastly, most existing city systems are nearly 100 years old (there are 700 water main breaks a day in the United States and on one memorable day in April, Los Angeles had six breaks in one day all within three and a half miles). All of these things take money.

Given the state of California’s economy, where will the money come from? Historically the people have paid for infrastructure either through bonds or in user fees. However, it is unclear if the willingness and the money is there to do that this time.

An alternative is the private sector, in what are commonly known as public-private partnerships. Under this type of arrangement water stays a public resource but the infrastructure may be designed, built and/or operated by a private company.

In California and the United States as a whole, about 15 percent of water systems are privately owned. Worldwide about 85 percent of water systems are privately owned. In the United States there has been an historic distrust of the private sector in the water arena (unlike the delivery of services such as electricity or natural gas). If that does not change the public will need to be willing to spend substantial sums on infrastructure or risk a downgrade in the quality and reliability of our water supplies.

The issues raised in “Last Call at the Oasis” are real and pressing. It is unfortunate that it seems so difficult to raise public consciousness around our most important resource. However if we don’t confront these issues soon and begin to grapple with the law and policies surrounding them the consequences may be very dire indeed.

Eric L. Garner is the managing partner of the law firm Best Best & Krieger LLP, where his practice focuses on water rights. He has litigated cases and negotiated key agreements involving major water bodies across California, including the Sacramento-San Joaquin Delta, the Mojave River, the Santa Ana River and the Antelope Valley groundwater basin. Garner co-authored “California Water,” widely considered the preeminent text on the history, policy and law surrounding the state’s most precious natural resource. He can be reached at