Water knowledge flows between the driest places on Earth

By Chris McKay (CSIRO) and Alejandra Cuevas (CSIRO Chile)July 10th, 2016

Australian water management expertise is informing management of water resources in Chile.
Aerial view of the Atacama Desert in Chile
This aerial view shows beautifully the Chilean Atacama Desert around the ESO Paranal Observatory, home to the Very Large Telescope (seen at the bottom right). Close to the VLT, one can see the dome of the VISTA survey telescope, and to the right, the Paranal Residence and basecamp. The high peak in the distance is the 6739-metre high volcano belonging to the Andes, Llullaillaco. Also in the image, to the middle left, one can see an isolated peak with a curvy road leading to its summit. This is Cerro Armazones, the selected home for the future European Extremely Large Telescope (E-ELT).

The Atacama Desert in Chile. Image: ESO/M. Tarenghi.

When it comes to dry places, it doesn’t get much drier than the Atacama Desert in the north of Chile—there are some sections in which rainfall has never been recorded. But Chile, the 4000 km long strip of a country clinging to the west of South America, is a nation of extremes. In the lower half of the country, from about Santiago to the southern tip, water is far more common—in fact, the amount of water available per citizen in Chile is over eight times the global average according to the World Bank’s estimates. This means that for the country as a whole, water availability is high—it is just not very evenly distributed.

When you consider that the Atacama also contains Chile’s richest mineral deposits (predominantly copper), as well as successful irrigated agricultural enterprises and local populations to sustain, and that all of these require water, then it becomes clear there are some unique water management challenges. (If you’re wondering at this point how there is any water at all for these activities, the glaciers and snow cover on the Andes mountain range bordering the desert to the east feed rivers and aquifers in the region.)

Copper mining is probably the most important industry for Chile’s economy, contributing about 15 per cent of GDP and accounting for as much as 60 per cent of the nation’s exports—so getting the water management settings right is an issue of national importance.

This is where Australia comes in. A nation that, despite having its own share of well-soaked areas around the coastline—particularly in the north—is considered the driest inhabited continent on the planet (only Antarctica is drier). Having endured through sustained periods of drought, like the Millennium Drought of 1997–2009, Australia has in its scientists and resource managers a deep pool of water management knowledge to tap. Like in Chile, Australian water management needs to take account of various water uses: mining and agricultural industries, the environment and biodiversity, cities and towns, and recreation.

The Chilean Government called on this experience when they engaged CSIRO to conduct an assessment of water resources and their management in the Copiapó Basin, one of the Atacama region’s river basins. It was a comprehensive investigation into the status of water rights, governance and water management options, which was delivered to Chile in 2012.

It was around the same time that CSIRO Chile was being established, with CSIRO having won a Chilean government contract to set up a Centre of Excellence for applied mining research in the country. With water resources being a critical consideration for mining development, CSIRO Chile built their own water resource research capability, with connections back to expertise in Australia, and have continued and expanded upon the initial Copiapó research.

Dr Edmundo Claro

Dr Edmundo Claro. Image: ESO/M. Tarenghi.

“The estimations are that approximately 6000 litres per second are extracted from the aquifer and it is being replenished at about 3000 litres per second,” says Dr Edmundo Claro, Research Program Director for Land and Water at CSIRO Chile.

“It’s being depleted. And so one of the most important challenges is how do we manage so that no more is being consumed than is being recharged naturally?”

Dr Claro and his team, supported by Australia’s aid program and the Chilean water authority Dirección General de Aguas (DGA), have been looking into options for responding to and avoiding water supply shortfalls and water quality problems in the Copiapó River Basin. They came up with a framework for water management planning in the basin that integrates all factors, from water governance, to hydrology, requirements of industry and communities, and water availability and use. It’s an approach known as Integrated Basin Management. The Chilean Government is considering this as they continue to develop the region’s water management structures.

Out of the desert

The Land and Water team of CSIRO Chile have more recently turned their attention to the less parched parts of the country further south, like the Rapel Basin in the O’Higgins Region of central Chile. The O’Higgins Region Government has commissioned CSIRO Chile, through their Innovation Fund, to develop an integrated management plan for the Rapel Basin.

“The main objective in Copiapó, the challenge, is how to get water users to adapt to the natural recharge of the aquifer. In Rapel, that’s not the problem,” says Dr Claro.

“In Rapel, there is water, but water is expected to get more scarce in the future because of climate change, because of more demand, and also because tourism and environmental groups are pushing for more water for the environment—and this is a tendency we think will grow more in the future.”

The project team will be applying some of the approaches that have been shown to be successful in Australia, such as a participatory approach to the development of integrated management plans. This involves bringing together all the water users and stakeholders, through a series of workshops, to have input into the plan that will ultimately apply to them.

“We like the way CSIRO approaches water management in Australia and the necessary modifications that have been made there, like socialising plans from the beginning, before their implementation,” says Graciela Correa, one of the project team members and Manager of the Federation of Water Surveillance Groups for the O’Higgins Region.

Dr Claro says as well as bringing stakeholders together, they will also be ensuring the integrated management plan is backed up by the best available science. At a practical level, he says, the objective of the project is to determine what tools the local water managers need to improve their management of the water resource.

“They feel the way they make decisions has worked, but they’re not sure it will continue to work in the future. They are using very traditional ways of making decisions, which they have used successfully for years, and now they want something more sophisticated, more scientific to do that. And that’s what we’re trying to help with.”

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