What the US can learn from Iran on water issues

Contributed reporting from Ali Mirchi, Oklahoma State University; Amir AghaKouchak, University of California, Irvine, and Kaveh Madani, Yale University

The 2021 water year ended Sept. 30, and it was one other sizzling, dry 12 months within the western U.S., with almost the entire region in drought. Reservoirs very important for farms, communities and hydropower have fallen to harmful lows.

The most important blow got here in August, when the U.S. authorities issued its first water shortage declaration for the Colorado River, triggering water use restrictions.

In response, farmers and cities throughout the Southwest are discovering new, typically unsustainable methods to fulfill their future water wants. Las Vegas opened a lower-elevation tunnel to Lake Mead, a Colorado River reservoir the place water ranges reached unprecedented lows at 35 percent of capacity. Farmers are ratcheting up groundwater pumping. Officers in Arizona, which is able to lose practically one-fifth of its river water allotment underneath the brand new restrictions, even floated the thought of piping water hundreds of miles from the Mississippi River.

These methods conceal a extra basic downside: the unchecked development of water consumption. The Southwest is in an “anthropogenic drought” created by the mix of pure water variability, local weather change and human actions that repeatedly widen the water supply-demand hole.

In the long term, this will result in “water bankruptcy,” which means water demand invariably exceeds the availability. Making an attempt to handle this by cranking up water provide is destined to fail.

Dozens of dead almond trees rowed up on their sides in a field.

A California farmer tore out useless almond timber in July due to an absence of water to irrigate them. Picture courtesy of Getty Photos through Robyn Beck

Greater than 7,000 miles away, Iran is grappling with water issues which might be much like the U.S. Southwest’s however extra extreme. One of many driest years up to now 5 a long time, on the again of a number of a long time of mismanaged water assets, introduced warnings of water conflicts between Iranian provinces this 12 months.

As environmental engineers and scientists — one of us can be a former deputy head of Iran’s Division of Atmosphere — we’ve intently studied the water challenges in each drought-prone areas. We imagine previous errors within the U.S. and Iran provide vital classes for future plans within the U.S. Southwest and different areas more and more experiencing drought and water shortages.

Groundwater pumping: A short lived repair with penalties

As the availability of water from the Colorado River diminishes, Southwest farmers are placing more straws into already declining groundwater that accrued over 1000’s to hundreds of thousands of years. However that may be a short-term, unsustainable resolution that has been tried across the U.S. and around the globe — with main penalties. The High Plains Aquifer and California’s Central Valley are simply two examples.

Iran presents a case research in what can go fallacious with that strategy, as our analysis exhibits. The nation nearly doubled its groundwater extraction points between 2002 and 2015 in an try to help a rising agricultural business, which drained aquifers to depletion. As its water tables drastically declined, the groundwater’s salinity elevated in aquifers to ranges that will not be readily appropriate for agriculture.

Whereas there isn’t any simple resolution, numerous actions are potential.

As water-filled pores within the soil are drained, the load of the overlying floor compresses them, inflicting the aquifers to lose their water holding capability and accelerating land subsidence. Iran’s capital, Tehran, with greater than 13 million residents, subsided more than 12 feet between 2003 and 2017. Equally, some areas of California are sinking at a fee of as much as 1 foot every year.

Interbasin water switch: A Pandora’s field

One other proposal within the Southwest has been to pipe in water from elsewhere. In Could, the Arizona legislature urged Congress to provoke a feasibility research to bring Mississippi River water to replenish the Colorado River. However that, too, has been tried.

In Iran, a number of interbasin water switch tasks doubled the move of the Zayandeh Rud, a river within the arid central a part of the nation. The influx of water supported unsustainable development, creating demand without enough water to support it. In dry years now, nobody has sufficient water. Many individuals in Khuzestan — the area supplying water to central Iran — misplaced their livelihood as their farms dried out, wetlands vanished and livestock died of thirst. Individuals in central Iran additionally misplaced crops to the drought as incoming water was reduce. Each areas noticed protests turn violent this 12 months.

A couple walk on what was once a riverside path. The river bed is dry and cracked.

Iranians stroll close to a bridge in-built 1602 over the Zayandeh Rud in Isfahan. Picture courtesy of Getty Images through Atta Kenare/AFP.

California diverted water from the Eastern Sierra Nevada to help Los Angeles’ development within the early 1900s, turning the once prosperous Owens Lake Valley into a dust bowl. Prices of mitigating mud storms there exceed $2 billion. In the meantime, California wants extra infrastructure and funding to fulfill its water demand.

One other venture, the California Aqueduct, was constructed within the Nineteen Sixties to switch water from the Sacramento-San Joaquin Delta in Northern California to the Central Valley and southern elements of the state to help agriculture and a few city demand. This additionally didn’t shut the water demand-supply hole, and it pushed economically and culturally vital native fish species and ecological methods within the delta to the point of collapse.

Trying forward in gentle of looming water chapter

Because the continued inflow of inhabitants into the U.S. Southwest raises water demand within the face of shrinking water provide, we’ve got to wonder if the Southwest is heading towards water chapter.

Whereas there isn’t any simple resolution, numerous actions are potential.

First, acknowledge that water shortages can’t be mitigated solely by rising water provide — it’s additionally vital to handle water demand.

There may be nice potential for water financial savings via efficient irrigation and precision agriculture methods, which may maintain agriculture viable within the area.

Cities can save water by curbing outside water losses and extra water use, akin to on decorative lawns. Californians efficiently reduced its water demand by more than 20 percent between 2015 and 2017 in response to extreme drought circumstances. Replanting city landscapes with native drought-tolerant vegetation may also help preserve water.

On the availability aspect, communities can contemplate nontraditional water sources, water recycling and reuse in all sectors of the economic system, and routing runoff and floodwaters to recharge groundwater aquifers.

Emerging technological solutions may enhance water assets in some areas, together with fog water collection, which makes use of sheets of mesh to seize moisture from fog, and desalination vegetation that flip seawater and saline groundwater into ingesting water. One new desalination plant deliberate for Huntington Seashore, California, is awaiting final approval. Environmental penalties of those measures, nevertheless, ought to be rigorously thought-about.

The Southwest monsoon returned this summer season after a record dry previous year and a half within the area, but it surely wasn’t sufficient to finish the drought there. Forecasts recommend a high chance that a La Niña pattern will develop over the winter, which means the Southwest is probably going in for an additional drier-than-normal begin to 2022.

Iran is already in water chapter, with demand exceeding provide. It is going to take much more than a moist 12 months to alleviate its water shortages.

This text is republished from The Conversation underneath a Inventive Commons license.

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