Avoiding Water Bankruptcy in the Drought-Troubled Southwest: What the U.S. and Iran Can Learn from Each Other

Iran offers a case study in what can go wrong with that approach, as our research shows. The country nearly doubled its groundwater extraction points between 2002 and 2015 in an attempt to support a growing agricultural industry, which drained aquifers to depletion. As its water tables drastically declined, the groundwater’s salinity increased in aquifers to levels that may no longer be readily suitable for agriculture.

As water-filled pores in the soil are drained, the weight of the overlying ground compresses them, causing the aquifers to lose their water holding capacity and accelerating land subsidence. Iran’s capital, Tehran, with more than 13 million residents, subsided more than 12 feet between 2003 and 2017. Similarly, some areas of California are sinking at a rate of up to 1 foot each year.

Interbasin Water Transfer: A Pandora’s Box
Another proposal in the Southwest has been to pipe in water from elsewhere. In May, the Arizona legislature urged Congress to initiate a feasibility study to bring Mississippi River water to replenish the Colorado River. But that, too, has been tried.

In Iran, multiple interbasin water transfer projects doubled the flow of the Zayandeh Rud, a river in the arid central part of the country. The inflow of water supported unsustainable growth, creating demand without enough water to support it. In dry years now, no one has enough water. Many people in Khuzestan – the region supplying water to central Iran – lost their livelihood as their farms dried out, wetlands vanished, and livestock died of thirst. People in central Iran also lost crops to the drought as incoming water was cut. Both regions saw protests turn violent this year.

California diverted water from the Eastern Sierra Nevada to support Los Angeles’ growth in the early 1900s, turning the once prosperous Owens Lake Valley into a dust bowl. Costs of mitigating dust storms there now exceed US$2 billion. Meanwhile, California needs more infrastructure and investment to meet its water demand.

Another project, the California Aqueduct, was constructed in the 1960s to transfer water from the Sacramento-San Joaquin Delta in Northern California to the Central Valley and southern parts of the state to support agriculture and some urban demand. This also did not close the water demand-supply gap, and it pushed economically and culturally important native fish species and ecological systems in the delta to the point of collapse.

Looking Ahead in Light of Looming Water Bankruptcy
As the continued influx of population into the U.S. Southwest raises water demand in the face of shrinking water supply, we have to wonder whether the Southwest is heading toward water bankruptcy.

While there is no easy solution, a number of actions are possible.

First, recognize that water shortages cannot be mitigated only by increasing water supply – it’s also important to manage water demand.

There is great potential for water savings through efficient irrigation and precision agriculture systems, which could keep agriculture viable in the region.

Cities can save water by curbing outdoor water losses and excess water use, such as on ornamental lawns. Californians successfully reduced their water demand by more than 20% between 2015 and 2017 in response to severe drought conditions. Replanting urban landscapes with native drought-tolerant vegetation can help conserve water.

On the supply side, communities can consider nontraditional water sources, water recycling and reuse in all sectors of the economy, and routing runoff and floodwaters to recharge groundwater aquifers.

There are also emerging technological solutions that could boost water resources in some regions, including fog water collection, which uses sheets of mesh to capture moisture from fog, and desalination plants that turn seawater and saline groundwater into drinking water. One new desalination plant planned for Huntington Beach, California, is awaiting final approval. Environmental consequences of these measures, however, should be carefully considered.

The Southwest monsoon returned this summer after a record dry previous year and a half in the region, but it wasn’t enough to end the drought there. Forecasts now suggest a high chance that a La Niña pattern will develop over the winter, meaning Southwest is likely in for another drier-than-normal start to 2022.

Iran is already in water bankruptcy, with demand exceeding supply. It will take a lot more than a wet year to alleviate its water shortages.

Mojtaba Sadegh is Assistant Professor of Civil Engineering, Boise State University. Ali Mirchi is Assistant Professor of Water Resources Engineering, Oklahoma State University. Amir AghaKouchak is Professor of Civil & Environmental Engineering, University of California, Irvine. Kaveh Madani is Visiting Fellow, Yale University. This article is published courtesy of The Conversation.