West Plains aquifer falling
The aquifer supplying water to communities on the West Plains area west of Spokane is being pumped faster than it can replenish itself, raising the prospect of a water shortage.
In some places, the groundwater level has dropped by as much as 100 feet in recent years, according to the Washington Department of Ecology.
A prolonged drought is being blamed. So is the region’s growth and homeowners’ seemingly unquenchable thirst for green lawns.
Whatever the cause, officials from Airway Heights, Four Lakes, Medical Lake, Cheney, Spokane County, Fairchild Air Force Base and the state have begun working together to address the problem before it reaches a crisis level. One idea being floated is pumping water from the Spokane Valley-Rathdrum Prairie aquifer to the West Plains.
“All we have on the table is talk, and talk’s good right now,” said the Department of Ecology’s Guy Gregory. “If these communities are going to continue to grow, they’re going to need more water.”
The agency stopped issuing new water rights for the area in the early 1990s.
Little is known about the West Plains aquifer, but experts say it’s not nearly as big as the aquifer that supplies 500,000 people in Spokane and Kootenai counties. Unlike the Spokane Valley-Rathdrum aquifer – which is compared to a giant, gravel-filled bathtub – the West Plains aquifer consists of water running through fractures in thick slabs of basalt.
The Rathdrum aquifer is also fed by huge lakes and heavy snowfall from Idaho Panhandle mountains. The West Plains aquifer sucks up only the scant rain and snow that falls in the arid reaches west of Spokane.
Two weeks ago, Medical Lake lowered its well pump by 170 feet to ensure a steady source of water during summer, when demand is highest, said Doug Ross, the city’s administrator. The city has instituted strict summertime lawn-watering policies. New water rates have also been implemented that increase prices with higher use.
“For the sake of green grass, people seem willing to pay it,” Ross said. “People like their lawns. That’s really what we’re talking about. In the wintertime, we don’t have a problem.”
Bringing in more water would help, but Ross said the ultimate solution will probably be found in increased water conservation and by such practices as using treated wastewater for irrigation. “We need to plan for the future,” Ross said. “We need to get a grip on this.”
Organizing the major water users to work together is a huge start, said Rob Lindsay, water resources manager for Spokane County. The region has four separate surface water planning areas, which help ensure wise use of water on top of the ground, but these four watershed areas sit atop the same aquifer, making unified management tough.
“It’s a failing in the system,” Lindsay said. “Irrespective of what watersheds they’re in, we need to address it as a whole. We need to raise awareness in all of the affected watersheds.”
If the communities worked together, their case could also have more clout in the state Legislature or if they were to seek federal grants, Lindsay added.
Some wells could run dry, but not enough is known about the aquifer to predict when, Lindsay said. “It could be a few years. … We’re definitely seeing groundwater lowering on an annual basis.”
As the groundwater drops, the prospect for conflicts rises. Some believe the larger wells are beginning to interfere with one another.
Pumping water from the Spokane River or Spokane Valley-Rathdrum aquifer to the West Plains is being discussed, but Lindsay said that would face huge regulatory hurdles.
Fairchild Air Force Base gets most of its water from the Spokane Valley-Rathdrum aquifer. Officials at the base asked that the location of these wells not be published for security reasons, but they said the water is brought to the base through a 16-inch-wide, 11-mile-long pipe.
The base’s demand for water has declined dramatically in recent years, thanks to improvements in leak detection and more efficient irrigation, said David Luders, a civil engineer at the base. Fairchild, which is the largest employer in Spokane County, uses about 800,000 gallons of water during the winter. Summer use spikes to about 4.5 million gallons. Still, the pipe has the capacity to pump more water, said Luders, who stressed he was speaking only as an engineer involved in the aquifer issue and not on behalf of the base. In theory, at least, the pipe could help replenish the dwindling West Plains aquifer.
Fairchild also has an emergency well on base. The well has been declining in volume in recent years, from about 900 gallons per minute to 725 gallons. It’s still more than enough to meet potable water demand on the base, but the dropping water supply is a concern for officials who want to make sure there’s always enough at hand, should there be a crisis or if the main pipeline fails, Luders said.
“That’s why we’re interested in the fate of the West Plains – it’s our backup,” he said.
Rachael Paschal Osborn, a Spokane attorney and conservationist who specializes in water issues, said she would be highly skeptical of any plan to use the Spokane Valley-Rathdrum aquifer as an antidote for water shortages elsewhere. It would be illegal if the transfer took away water from those who hold water rights on the Rathdrum aquifer or in the Spokane River, added Osborn, who is founder of the Columbia Institute for Water Policy.
Osborn hopes conservation is seen as the best fix. “We’ve really got to get out of this mindset we have that the aquifer is infinite,” she said. “This is a problem everywhere in our community.”
Gregory, with the Department of Ecology, pointed out that communities are trying to conserve. “There’s not a lot of green grass out on the West Plains,” he said.