The Golden State’s big thirst

For a glimpse of the future of our planet, take a look at the drought gripping California – and take heart.

Ignore the hand-wringing about how it is all the fault of man-made global warming (it is not). Forget the apocalyptic talk of the worst drought in the history of America’s most populous state (true, but California has been a state for only 160 years).

Focus instead on how California is displaying that most potent yet underrated of human traits: adaptability.

Over the four years since the drought descended on the Golden State, a trickle of stories about ingenuity and determination has turned into a flood.

What began as polite requests to cut water use has spawned a host of initiatives.

During the height of summer these past few months, residents have been achieving savings of more than 30 per cent, with one area hitting 40 per cent.

Time-honoured methods such as hosepipe bans are being supplemented by the quintessential 21st century phenomenon of social media.

Companies or neighbourhoods seen flouting the rules risk being outed on Twitter and Facebook – alongside photographic evidence of their profligacy.

As this is California, there is, of course, an app for that: DroughtShame.

Meanwhile, the main reservoir of Los Angeles has been turned into a 70-hectare ball pit, having been covered with millions of black plastic spheres.

Originally used to combat water quality issues, they are now being deployed to cut evaporation losses.

And these quick fixes hide an even more impressive reality.

The current drought is just the latest to have hit the state since the 1970s. What is different is that since then the population has almost doubled.

The finger of blame has pointed in various directions over the years. What has not changed is the view that, regardless of the cause, a long-term solution must emerge.

Californians have been working on it for years and now it is starting to come together. Like so much about this drought, however, it has a few surprises.

Some have their roots in the fact that the current drought is not due to a lack of rain – there is never much of that – but to a lack of snowfall.

Most Californians live in the south of their vast state but get the majority of their water from the melting snow of the Sierras in the north.

In the past few years, the snowpack has not been replenished and this summer it finally disappeared completely.

Global warming seems the obvious explanation but again, the reality is different.

Research by a team led by Prof Richard Seager, of the Lamont Doherty Earth Observatory, Columbia University, suggests that the culprit is just natural variability in the weather, with climate change playing a relatively minor role.

An unfashionable conclusion, perhaps, but one that highlights the ability of the climate to spawn mayhem without help from humans.

It also frees solutions from the endless bickering over the reality or otherwise of global warming. There is no need to rely on computer models: the lessons of history alone show what is possible.

In 1917, California was hit by a drought that persisted more or less unbroken for 20 years. Any long-term strategy worth the name must be able to cope with such events.

Cutting down on leaks and waste, while boosting recycling and storage of rainwater are clearly part of the answer.

As Charles Fishman, author of The Big Thirst, pointed out recently in The New York Times, it makes no sense for water-starved Los Angeles to have a huge drains system that collects what rain does fall – only to dump it straight into the Pacific.

These measures are being backed by new legislation. In April, governor Jerry Brown introduced laws that for the first time impose water restrictions on supply agencies, and require reports on water use from farmers.

At a national level, there are plans in congress to introduce laws requiring more water facilities to be built.

Technology is also helping out. San Diego is now the site of the largest seawater desalination plant in the western hemisphere. Being built at a cost of US$1 billion (Dh3.67bn), it will use so-called reverse osmosis to force water through polymer membranes, stripping the salt and other impurities from the seawater.

The process is, however, notoriously expensive – that one plant alone is expected to use as much power as a town with 30,000 homes.

With at least 15 such desalination plants being considered across the western state, the economic cost is causing concern.

The solution may lie in technology now being installed in Abu Dhabi – and attracting interest in California.

Working with four international partners, clean energy company Masdar is creating a pilot desalination plant at Ghantoot, near the Abu Dhabi-Dubai border.

This will showcase advanced technologies that use renewable energy to power the process at lower cost.

This month, experts from Masdar travelled to San Diego to give a series of workshops on the current state of play.

Further ahead, California will benefit from new desalination techniques based on radically new forms of filtering membranes.

These include a process developed by a joint US-Saudi Arabian team based at the Massachusetts Institute of Technology, whose graphene-based membranes could cut desalination energy costs by half.

While the technology may be new, the strategy is one as old as humanity: adapt and survive.

America has been here many times before, and triumphed. When the Midwest was hit by the Dust Bowl droughts of the 1930s, its farmers responded by planting hardier crops, diversifying production and improving irrigation.

As a result, when an even greater drought struck in the 1950s there was no repeat of the calamity.

Ironically, the biggest threat to California’s plans could come with the return of snow and rain this winter.

Far off the coast, the El Nino phenomenon is stirring – a strange warming of the Pacific that triggers extreme weather. Many are hoping that El Nino will bring snow and rain to California.

The relief will be welcome. But we should all hope it will not derail this demonstration of how humans cope when nature does its worst.

Robert Matthews is visiting professor of Science at Aston University, Birmingham