Demand presents risks to water supplies

SASKATOON, Saskatchewan, Feb. 21 (UPI) -- Drinking water from coastal groundwater is more at threat from human activity than from rising sea levels due to climate change, Canadian scientists say.

Geoscientists from Canadian universities examined data from more than 1,400 coastal watersheds and said they found most are relatively unaffected by rising sea levels.

The aquifers are seeing more impacts from humans pumping water from wells for drinking, domestic use and irrigation, a release from the University of Saskatchewan said Tuesday.

"The bulk of the research in recent years has focused on climate change effects on coastal groundwater but increases in water demand could be more important," researcher Grant Ferguson said. "This is particularly true in growing coastal cities and towns where groundwater is often an important water supply."

Coastal aquifers are bordered by seawater that can start to migrate into them and into wells if too much fresh water is drawn out, the researchers said.

Rising sea levels could also cause seawater to enter aquifers, researchers said, but to date only problems related to pumping have been documented in Canada.

"Coastal aquifers are very vulnerable to increased water demand so we have real policy opportunities," researcher Tom Gleeson from McGill University in Montreal said. "We can reduce consumption of groundwater in coastal areas or manage groundwater use wisely."

Twenty-five percent of Canadians rely on groundwater with some areas almost totally dependent on the resource, researchers said.