THE SKOKOMISH River came to Dave Montgomery's attention a good 10 years ago, soon after Montgomery arrived in town to join the UW geology department


Flood of information

THE SKOKOMISH River came to Dave Montgomery's attention a good 10 years ago, soon after Montgomery arrived in town to join the UW geology department to practice his jawbreaking specialty, fluvial geomorphology. In English, that translates out as how and why river drainages take shape and behave as they do, and the behavior of the Skokomish, draining a small swath of the Olympic National Forest northwest of Shelton in Mason County, was distinctly peculiar.

"What really got my attention was listening to the weather people on TV," Montgomery says. "'Well, looks like the Skoke is flooding again, ha ha.' It was like this big joke."

Winter flooding isn't unknown on any of the streams draining off the mountains round Puget Sound, but the Skokomish overdoes it: "It's always the first to flood each winter, and it keeps on flooding—three, four, six times a year. This is not normal stream behavior. It was clear that the Skoke was one sick stream."

Montgomery himself never got around to looking into the Skokomish's odd behavior, but a few years ago it was among a number of research topics he suggested to a geology master's degree candidate named Cher饠Stover, who pounced on the opportunity. Montgomery sent Stover off to the Tacoma offices of the United States Geological Survey (USGS), where she found a trove of information: river height and volume information going back to 1926, when the first of two dams was built on the upper reaches of the Skokomish to supply power for the city of Tacoma.

Until about 1950, the record showed, the Skokomish behaved pretty much like other area streams, flooding in years of heavy precipitation, running low in dry winters. But after about 1960, the pattern changed. Average water flow remained within normal limits, but incidents of flooding rose steadily decade after decade. The USGS records made it obvious why: "The same amount of water's coming down the stream as 40 years ago, but high-water levels are a meter higher. And the reason is that the stream is now a meter and a half shallower than it was before," its bed filled in by sediment.

The water-flow, water-depth, and flooding statistics are a matter of irrefutable record; identifying the source of the sediment choking the Skokomish's channel calls for inference, but Stover and Montgomery are pretty sure they know where it came from. "The two Cushman dams are on the North Fork of the river," says Montgomery, "upstream of where it joins the South Fork. The dams cut the winter stream flow significantly but don't seem to have had any effect on flooding."

But starting in the '50s and '60s, access roads were built and the river's catchment area was very aggressively logged. Clear-cutting and debris removal and burning strip the land of much of its capacity to retain precipitation and retard its runoff, leading to greater erosion of topsoils and stream banks. A lot of the land that once lay beneath the forests of northwest Mason County is probably to be found now beneath the waters of the Skokomish, elevating them more and more often above the stream's normal banks and sluicing them out over flats and farmlands downstream.

This poses a very pretty legal problem, should any of the property owners downstream choose to take the matter up in court. Common law says that if you choose to live or do business in a known flood area, you've got no claim for damages when you find yourself wading to work. But this admirably simple principle has gotten badly bent out of shape in recent years, thanks to the sheer political clout of hundreds of thousands of residents of flood-prone areas along the Missouri and Mississippi rivers.

Even under the traditional buyer- beware rule, the legal status of land along the banks of the Skokomish isn't as tidy as it might be. Suppose I buy land along a stream with a record of flooding for a few days once every few years. Now suppose the few days turns into a few weeks, and once every few years turns into every damn November, December, and January. And suppose I come across a reputable scientific study that shows the additional inundation is not due to capricious acts of God but to very specific, self-interested actions of identifiable individuals, corporations, and municipalities? Do I have standing to sue? It would sure look to be worth a try.

And it's being tried. The Skokomish Indian Reservation lies directly in the path of the river's persistent overflowings, and in 1999 the tribe brought suit for redress in federal court for the Western District of Washington against the United States of America, Tacoma Public Utilities, and the city of Tacoma, proprietor of Cushman and Lower Cushman dams.

Given the way right-wing judges have been willing to call it "wrongful taking" every time a governmental entity looks cross-eyed at someone's private property, the tribe may well do nicely with the case. It won't save the river, of course. But you can't have everything.

For more on the legal and social dimensions of the Skokomish flooding case, see Cassandra Sweet's article in the December/January issue of Washington Law & Politics:

Roger Downey's science column appears every other week.

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