Water Becomes ‘Blue Gold’ as World’s Driest Desert Expands South in Chile

By Javiera Quiroga

July 6 — The world's driest desert is expanding south and Chile's capital is sitting in its path.

Santiago, a city of 7 million people 1,000 kilometers (622 miles) from the Atacama desert, is experiencing its driest year since 1966. Similar to California's situation with the Sierra Nevadas, little to no snow has fallen in the Andes Mountains that supply most of Santiago's water.

“Climatic zones are shifting south,” said University of Chile geography professor Francisco Ferrando. “Santiago is likely to move to a condition of a desert or semi-desert. What is happening is probably associated with global warming and there's no sign of it slowing.”

As its drought continues for an eighth year amid record high global temperatures, Santiago need only look 300 kilometers north to see how bad things can get. Farmers in the once-fertile valleys of the Choapa and Limari rivers that lived for generations on agriculture are ripping up orchards, losing livestock and in some cases abandoning homes as wells dry and waterways slow to a trickle.

Near the origin of the Limari river, La Paloma Reservoir—Latin America's largest for irrigation—is all but empty. Sluice gates are shut, the little water that remains doesn't reach the dam and most of the basin is dry, cracked earth. The image is repeated 30 kilometers away where Cogoti Reservoir is empty. Closer to Santiago, the Culimo Dam is dry.

Around the river valleys, fields are filled with the stumps of once-productive avocado trees and almond groves. Grapevines are a thatch of dried stems.

'Blue Gold.'

In search of water or “blue gold,” Adolfo Cortes has drilled five boreholes on his 187-hectare (475-acre) farm near Ovalle. None has produced any usable supplies.

After 25 years on the farm, Cortes has never seen anything like it. The 68-year-old already has ripped up 122 hectares of fruit trees and says the rest will be pulled if water levels in the Limari fall much further.

“If it doesn't rain in July, the year will be lost,” he said, staring across barren fields that once produced almonds and oranges. “We need at least 400 to 500 millimeters (15 inches) to normalize the situation, a couple of rainfalls won't help.”

Since 2010, Santiago has received only a third of its average rainfall as the La Nina climate phenomenon blocked weather fronts from moving up from the south, said Jason Nicholls, a senior meteorologist with AccuWeather Inc. Still, La Nina may not be the only reason.

“You have to suspect something else is going on because it has been so persistent for so long,” Nicholls said, referring to climate change.

1,000 Glaciers

Santiago doesn't behave like a city about to be engulfed by a desert. Swimming pools dot wealthier areas, automatic sprinkler systems water lawns and gardens are full of trees more suited for wetter zones.

Fed by snow melt from 1,000 Andean glaciers, the Maipo River supplies most of Santiago's water. The other river, the Mapocho, is “collapsed” with barely a trickle entering the city, according to Felipe Larrain, chief executive officer of Chile's largest water utility, Aguas Andinas SA.

“We have been working on this issue from the first day of the drought and that is why there have been no water restrictions,” Larrain said. Still, “the situation is much worse than we had predicted.”

Aguas Andinas can keep the taps running in Santiago for another year if Yeso Reservoir in the mountains has 50 million cubic meters in October, the CEO said. With a capacity of 220 cubic meters, Yeso currently holds 120 cubic meters.

Water Rights 

“The company's policy is to buy all the water rights we can, everything we can rent or agree with farmers,” Larrain said. “We haven't saved on costs.”

Much of its spending goes to wells that account for about 15 percent of Santiago's water supplies, an investment that is compensating for wells running dry, Larrain said.

With La Nina switching to El Nino in the region this year, Accuweather forecasts rains will return to Santiago in July. The question is how much and for how long.

Santiago, meanwhile, relies on water from glaciers dating from the last ice age that won't last many more decades, the professor Ferrando said.

To contact the reporter on this story: Javiera Quiroga in Santiago at jquiroga5@bloomberg.net

To contact the editor responsible for this story: Vivianne Rodrigues at vrodrigues3@bloomberg.net

 ©2015 Bloomberg L.P. All rights reserved. Used with permission