Energy producers face fierce competition for scarce water resources as they look to expand North America's shale gas boom into regions that are facing stresses due to overuse or inadequate supplies of fresh water.
Concerns about the demand for and contamination of local groundwater have long plagued the shale gas industry, which has been shut out of places like Quebec and New York State due to environmental concerns, and faces fierce political opposition in jurisdictions like Colorado and New Brunswick.
But as the industry looks to go global, a new study by the World Resources Institute (WRI) says development of some of the promising plays in China, Mexico, Argentina and Britain could be stymied by lack of access to fresh water. The study was released Tuesday at a world water week conference in Stockholm.
"Water available could limit shale resources development on almost every continent," the institute's Paul Reig said in an interview from Stockholm. "There are areas where shale resources are located that face extremely high water stress or are very arid. There are already high levels of competition between users for what is available … And if industry does not have the right solutions, and that could pose barriers to development."
The WRI report assesses the water availability in 11 countries that lead the world in shale gas and tight oil resources, and finds that nearly 40 per cent of the area where shale resources are located face significant water crises.
In the United States, much of the shale gas and tight oil production is taking place in Texas, where competition for scarce water is fierce. In China, where the government has ambitious plans to develop its shale gas, some 61 per cent of the resource occurs in areas of high water stress or arid conditions. In Mexico, where new energy reforms aim to stimulate investment in shale gas field, roughly 50 per cent of the resource exists in areas of limited availability of fresh water.
Canada's biggest shale gas reserves are in northeastern British Columbia where water is relatively plentiful but availability varies by season. Competition for fresh water is tougher in areas of Alberta and Saskatchewan that produce gas and tight, light oil.
A typical shale gas well uses about five-million gallons of water for drilling and hydraulic fracturing (fracking), the technique of breaking open impermeable rock by blasting it with chemically-laced water. But that figure varies dramatically, depending on the structure of the rock and the extent of the hydrocarbon-bearing strata.
The WRI report urged industry to work in co-operation with other users and be diligent in assessing water risks, while governments should ensure the supply and demand for water is well-understood, and competing needs are properly balanced.
But availability of fresh water is only part of the story – the bigger concern is contamination of existing water supplies, said Adele Hurley, director of the program on Water Issues at University of Toronto's Munk School. A recent report by the Pennsylvania's Department of Environmental Protection documented 243 cases in which oil and gas companies had contaminated private water wells.
Faced with environmental concerns and limited supplies in some regions, the industry has been working to reduce its need for fresh water by recycling what it does use, targeting the fracks more efficiently, and employing gels and non-potable water.
"Wise water use is definitely something we put a lot of emphasis on," said Daniel Whitten, spokesman for America's Natural Gas Alliance, a lobby group in Washington, D.C. But he added the natural gas industry uses a small fraction of the amount of water that is sprayed on lawns and golf courses, or is used to run coal-fire or nuclear power stations.
Canadian companies and governments already meet many of the recommendations made in the WRI report, said Kevin Heffernan, executive director of the Canadian Society for Unconventional Resources. Still, they are working to identify salt-water aquifers that can be used instead of fresh water for fracking, he said.