Normally rainy cities in Washington state took the unusual step on Tuesday of asking residents and businesses to voluntarily cut back their water use by 10 percent, in response to unusually hot and dry weather.

Officials in Seattle, Tacoma, Everett and Bellevue announced that they have moved to the second stage of their conservation plans by enacting the voluntary reductions because of the potential for a water-supply shortage.

If conditions worsen, each city will decide whether to move to the mandatory phase and require customers to reduce the amount of water they normally use each day.

Alex Chen, Seattle Public Utilities' director of water supply planning, said it's too early to tell if the region will need to initiate the mandatory reductions. Officials monitor reservoirs and rivers on a daily basis and use models to decide how much water conservation is needed, he said.

"It's been a pretty unusual summer here with record hot temperatures in June and July and record dry conditions in May, June and July," he said. "If we continue to have the unusually hot and dry conditions, we'll have to go to stage 3."

This is not the first time the region has been threatened with drought conditions, Chen said.

"Over the past 40 years, it has happened a half-dozen times," he said. Officials had to activate the water-reduction plan in 2005, and they went to mandatory reductions in 1987 and 1992.

Brent Bower, a senior hydrologist with the National Weather Service in Seattle, said the combination of little snow last winter and a hot summer has led to water shortages.

"In essence, on top of having record-low snowpack, it was exacerbated by staying warmer and dryer than usual," he said. "Those two things back to back have put us in the drought."

Things could turn around when the fall rains return, he said. But that might not happen until October, and with the strong El Nino that's in place, that can't be counted on, Bower said.

In addition to threatening water supplies, the drought is causing rivers to drop and water temperatures to rise, which threatens fish, he said. Many area rivers have been closed to recreational fishing, he said.

Kelly O'Rourke, water conservation planner for Seattle, said they're reaching out to all customers, large and small, to voluntarily reduce their water use.

"We want people to be logical and asking them to pull back where it's appropriate," she said. "Folks who don't have landscapes can help by only washing their vehicles at places that recycle the water, or reduce their shower times."

If the cities have to go to the mandatory water reductions, O'Rourke said they have enforcement tools to help ensure it happens, including fees and surcharges.

"In past we haven't had to use those because customers responded well," she said. "They typically over-responded."


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