‘You’re floating in your drinking water’
Spokesman Review
By Becky Kramer
July 15, 2008
Subtitle: River, aquifer have close relationship
About 10,000 years ago, the Missoula Floods laid the bedrock for the region’s water supply.
An ice sheet crept across the Idaho Panhandle, damming the Clark Fork River and creating glacial Lake Missoula, which extended 200 miles to the east. The ice dam failed repeatedly, sending water, ice, and house-sized boulders roaring through the Columbia Basin.
During particularly ferocious floods, the water moved at freeway speeds of 65 mph. But during the ice dam’s waning years, the floodwaters slowed.
Gravels and cobbles sifted out. The porous glacial debris became the Spokane Valley-Rathdrum Prairie Aquifer – a source of drinking water for more than 500,000 people.
The aquifer was on our minds Saturday as we rafted about 15 miles of the Spokane River between Post Falls’ Corbin Park and Plantes Ferry Park in Spokane Valley.
“You’re floating in your drinking water,” said Guy Gregory, a supervisor in the Washington Department of Ecology’s water resource program. He made the trip in an 8-foot yellow pontoon boat with a fishing rod attached to the back.
The river and the aquifer are really the same water body, said Gregory, who was the Washington manager of a $3.5 million bi-state aquifer study. He took advantage of “teachable moments” on the water, even though it meant shouting back and forth between rafts.
Gregory’s booming voice helped. “He’s always the loudest guy in the group,” another ecology department official said.
Between Stateline and the Sullivan Road bridge, the Spokane River feeds the aquifer, losing about half its flow to underground gravels. At Sullivan Road, however, swimmers start noticing cool pockets in the river.
That’s where chilly water from the aquifer – about 49 degrees – percolates into the river, recharging its flows and providing cold water for a native redband trout population.
Last week, Spokane Mayor Mary Verner proposed reducing the summer demands on the aquifer by outlawing the use of sprinklers from noon to 6 p.m. during May through September. Violators could be fined $125.
It was a bold move for a city that prizes its green lawns. But the days of super-lush landscaping and free-for-all watering may be coming to an end. Spokane County’s per capita water consumption – 217 gallons per day – is about twice as high as the state average. The region needs to develop a water conservation ethic, local officials said.
The aquifer isn’t running out of water, Gregory said. Water from lakes, streams and precipitation recharges it. But sucking water for human uses out of the aquifer is reducing river flows by about 225 cubic feet per second. That’s roughly equal to the aquifer-recharge from precipitation.
“Nobody wants a dry river,” Gregory said. “It’s not good for the economy; it’s not good for our way of life. With more people moving here, we need to take some steps toward conservation.”
During Saturday’s rafting trip, we enjoyed unseasonably high flows along a wide, meandering stretch of the river. Mergansers, a fish-eating duck, dived along the shoreline. The water was clear enough to see suckers nosing the river bottom.
The sloping hillsides were relatively bare of development. Several people on my raft noted the sharp contrast from the built-up Idaho shoreline above Post Falls Dam.
In Washington, houses are set further back from the water. Stricter zoning laws – along with public land ownership – preserved a more-natural looking shoreline.
A diverse group of people were out using the river. We saw several other rafting parties, plenty of innertubers, and a few fisherman.
Kayakers played in the rapids near Sullivan Road. Homeless men camped nearby.
A public beach near the Harvard Road Bridge was also busy. The beach will close in late summer, while soils containing lead, arsenic and other heavy metals are removed or capped.
The metals, deposited over decades, came from upstream mining activity in Idaho’s Silver Valley. The beach is one of nine areas on the Washington side of the Spokane River identified for cleanup.
The work will make the site safer for wildlife, as well as people, said Zach Hedgpeth, Ecology’s coordinator on the project.
Trout spawn in the area. “They lay their eggs right in the contaminants,” he said.
Contact Becky Kramer at (208) 765-7122, or by email at beckyk@spokesman.com.
Slaughter of the horses
Early in the last century, people saw bleached horse bones along the Spokane River near the Idaho-Washington border. Col. George Wright, with superior howitzers and rifles, twice outgunned local Indian tribes then led his troops to this area where, on Sept. 9, 1858, roughly 800 horses were killed to prevent the Indians from waging further warfare. Soldiers pinned the herd against the north bank of the Spokane River, then led small groups of horses to a gravel bar to be shot. A monument to the horses is located on the Centennial Trail, two miles west of the state line.
Source: The Spokesman-Review archives
Building setbacks
Last month, Spokane County adopted a “critical areas ordinance” that prevents construction within 250 feet of the river. A 1970s shoreline ordinance required houses to be at least 50 feet from the river’s high-water mark. Older homes, built closer to the water, have “grandfather rights,” said Jim Falk, an associate planner with Spokane County. In addition, people can get exemptions from the 250-foot setback if the topography of their parcel limits where they can build on the property, he said.