Few areas here may see water rationing

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Residents of the Puget Sound region will probably survive this dry year without water rationing - except for a few communities whose wells have been nearly depleted by rapid growth.

The 1.4 million people served by Seattle Public Utilities, including 26 suburban districts, will have enough to drink if they meet a 10 percent voluntary conservation goal announced two weeks ago, predicts utilities director Diana Gale.

Everett and Tacoma city reservoirs, which provide water to most of Snohomish and Pierce counties, respectively, are so flush that shortage advisories haven't been issued.

But in Kent, Sammamish and Covington, a lack of winter rain has exposed the long-term exhaustion of aquifers. Water districts in those three cities, which serve 123,756 people, reported "high vulnerability" to shortages in a state survey released this week.

Tuesday, Kent declared immediate yard-watering restrictions, dividing users into odd and even watering days based on house numbers. The system that serves 54,056 people is expected to be 4 million gallons a day short of peak summer demand.

Water sources Surface water: runoff from rain and melted snow. The main source for urban Puget Sound dwellers, surface drinking water is typically stored in mountain reservoirs and piped to the cities. Ground water: rainfall that has seeped through the topsoil and resides in layers of wet gravel or soil called aquifers. Wells: deep shafts where ground water is pumped to the surface. An artesian well is where natural pressures push ground water nearly to the surface. Springs: natural fountains where ground water percolates to the surface, forming the source of a stream.

In Enumclaw and Issaquah, shallow wells or springs are nearly exhausted, but recent rains have helped prevent a crisis. Two inches of rain fell from April 1 to Tuesday at Seattle-Tacoma International Airport, a third above average. But since October, overall precipitation remains 11 inches below average.

For most Puget Sound communities, however, a relatively painless prognosis is at odds with drought-related ills around the state. Shortages in the hydropower system have in part led to higher electricity prices, while a lack of irrigation water in Eastern Washington threatens harvests.

But unless spring rains start dropping off, the pain for most water consumers here should be no worse than peer pressure to let a lawn go brown or a ticket for watering on the wrong day.

Reservoirs OK

The 3.1 million people in Snohomish, King and Pierce counties are divided into more than 100 water systems and draw from two kinds of supplies: surface water and ground water.

Surface water, the source for three-fourths of users, comes from mountain streams harnessed behind dams. Melting snow typically fills the four major reservoirs - Tolt, Chester Morse Lake, Howard Hanson and Spada Lake - by early June.

Snowpack above Seattle's two watersheds is only 55 to 60 percent of normal this year, the worst on record, said Gale. But while the Tolt Reservoir is expected to be 10 feet low, a new filtration plant lets Seattle suck out lower, dirtier water when the cleaner water is gone. And Chester Morse Lake, in the Cedar River Watershed, is likely to refill from rain and melting snow.

Everett's main Spada Lake Reservoir, on the Sultan River, is nearly brimming. The Sultan basin sits in a weather "convergence" zone that in an average year sees 166 inches of precipitation. Even in 2000 it soaked up 144 inches.

Tacoma's Howard Hanson Reservoir, on the Green River, doubles as a flood-control project, so its capacity exceeds urban water needs. Tacoma also has vast wells 1,000 feet beneath the city for hot summer days.

For some communities on ground water, supplies are more precarious.

From wells to fish

Well water comes from rain that seeps through the topsoil and settles in underground veins called aquifers. Aquifers have been stressed not only by low rainfall this year, but by new construction in the 1990s that smothered the topsoil with pavement.

Because streams are fed by the aquifers, the lack of water pits consumers against fish. The north fork of Issaquah Creek, which flows past Interstate 90, office parks, town houses and a new shopping center, has run dry in recent years because of development.

In the nearby 40,500-inhabitant Sammamish Plateau Water & Sewer District, whose well system includes two sites next to the north fork of Issaquah Creek, customers have been asked to conserve 20 percent more this year than last, a goal manager Ron Little says is unlikely to be met.

"We may have to become water police," he said.

During a north-fork dryout last summer, residents did not reduce water use as asked, even as their utility voluntarily released well water into the parched stream. Since then 1,000 more homes have joined the system. Still, the district refuses to pipe in Seattle water because many in the district don't want fluoridated, chlorinated city water.

North Bend, which enjoys 80 inches of rainfall a year, faces a slight chance of water restrictions.

The community's sole permitted source is an artesian spring below the north face of Mount Si, where geologic pressures squeeze water to the surface. After the city takes its share, leftover water gushes into the Snoqualmie River. If spills from the well decline, rationing could follow to ensure sufficient levels for fish.

New water rights have been denied in Covington and along the Snoqualmie-Snohomish river system, where a 1995 study found that flows are below minimal levels for salmon 121 days a year.

"In the past," said regional state Department of Ecology director Dan Swenson, "it's been real cheap and easy to get water, but those days are done. People have to look at conservation."

Saving the sockeye

The shortfall in Kent stems partly from plans in late summer to pump 2 million gallons of well water into Rock Creek, an imperiled sockeye-salmon stream.

Some water-short utilities will buy from their neighbors.

A pipeline from Tacoma to Seattle for South King County is proposed for 2005, while another extension will bring Seattle water to Issaquah by next year.

North Bend wants to tap a Seattle reservoir in two years, and small water trades for this summer are being negotiated. Kent bought water from Renton and is trying to open two new wells.

In the 29,200-customer Covington Water District, where wells are already down to August levels, water is being purchased and piped from Auburn and Seattle.

In the big-city surface-water systems, managers are optimistic that thrifty use will prevent shortages.

Demand by Seattle Public Utilities customers has not grown since the late 1970s, despite a 29 percent increase in population, said the agency's Gale. She credited education, low-flow fixtures in new kitchens and bathrooms, and smaller household sizes.

"When we asked for voluntary conservation," she said, "we were very confident. People step up when we ask them to step up."

If they don't, and spring turns dry, Seattle might resort to mandatory restrictions -- bans on daytime yard watering, limiting yard watering to two days a week, a ban on pressure-washing sidewalks and buildings, or temporary surcharges.

If a complete lawn-watering ban became necessary, as in 1992, new lawns in Seattle would be exempt, said Rich Gustav, a resource-conservation manager.

Seeping evangelism

Seattle's 15-year tradition of conservation evangelism is seeping into the suburbs, where this year's drought will test public support for saving water.

Bellevue, which is on the Seattle system, reduced consumption 13 percent early this month, said Mayor Chuck Mosher. City crews turned off the Downtown Park fountain and have cut park irrigation and city-vehicle washing by half. But the city won't lay a guilt trip on homeowners.

"I don't think it's a badge of courage to have a brown lawn in Bellevue," Mosher said. "I don't think we'll go that far."

Mike Lindblom can be reached at 206-515-5631 or mlindblom@seattletimes.com.