Last April, Olympic National Park began distributing 5,000 “Last Dam Summer” buttons.
Park officials were heralding the 2011 tear-down of the Elwha River’s two dams, an estimated $350 million history-making effort to reopen 65 miles of spawning habitat to restore the waterway’s once vigorous, now tepid salmon run.
“This is the last summer before big changes come to the Elwha Valley,” Olympic National Park spokeswoman Barb Maynes said last week.
The first big change comes in about a week, when Lake Mills closes to the public for eight weeks while a pilot channel is dug to route sediment once 210-foot Glines Canyon Dam and 108-foot Elwha Dam do come down.
The dams’ actual demise will not begin until Sept. 15, 2011. That project is scheduled to end by March 2014.
So beyond being a clever double-entendre, what will happen next summer that makes this the “Last Dam Summer”?
The answer has more to do with what will happen to lakes formed by two dams than the dams’ actual demolition, park officials say.
Think of a bathtub ring, Elwha Restoration Project Manager Brian Winter suggested Thursday
Beginning about mid-June, 2011, Lake Mills, which sits behind Glines Canyon Dam inside Olympic National Park, and Lake Aldwell, behind Elwha Dam outside the park, will be drawn down, gradually exposing hill slopes that were stripped of trees about a century ago, just before the dams were built.
“People will see a big bathtub ring, where now they don’t see one,” Winter said.
Another phase of the project will affect the boating and fishing public as the lakes are emptied.
The two lakes will be closed permanently some time next summer, as will boat launches at both lakes, though Winter was not sure when.
It’s likely kayaking will be allowed, but Winter didn’t know for how long.
Also next summer, probably around mid-July, workers will begin shutting power off at the dams.
“That’s a biggy,” Winter said.
The dams produce a combined 19 megawatts. Glines produces twice as much as its sister dam.
“We want to run them as long as we can to produce power to the point we need to start decommissioning them and turn them over to the contractor,” Winter said.
Specific time lines on many aspects of the tear-down process won’t be known until after the demolition contract, which will be between $40 million and $60 million, is awarded some time before Sept. 30.
The bidding process is so secret that, under federal law, even the bidders’ names are not now being made public.
Some aspects of the $350 million river restoration project — the National Park Service, which is in charge of the project, has up to $360 million to spend — have already been completed or will be completed before next summer.
Still unfinished is a Lower Elwha Klallam tribal fish hatchery that will help restore the river’s legendary salmon run from its present, dismal annual return of some 3,000 salmon a year to its former 400,000 annually, the park service has said.
The hatchery is 50 percent built and is on schedule for completion by May 2011.
By 2039, the river is expected to be replenished to its pre-dam level with all five species of Pacific salmon.
Once the river is set free, it will rise 2 ½ feet, threatening the Lower Elwha Klallam reservation, which sits where the Elwha empties into the Strait of Juan de Fuca.
A contract has been awarded to build up a levee at the reservation. It should be completed by September, Winter said.
The barrier will be built up to withstand 200-year floods.
In addition, an outfall pipe at the Nippon Paper Industries’ Port Angeles will be extended 1,400 feet into the Strait.
The pipe will carry sediment that is removed from the river water that Nippon uses to make paper.
A treatment plant for river water that is sent to the mill and the state and tribal fish hatcheries will remove sediment but not to the extent Nippon needs.
No further treatment will be needed at the fish hatcheries, Winter said.
A treatment plant — the Elwha Water Facility — was completed in April.
It and Port Angeles’ new municipal water plant were the biggest single construction projects needed for dam removal.
The city’s treatment plant, also needed to remove sediment trapped behind the dams, started up in February.
A fish-rearing facility on Morse Creek and a greenhouse that is growing plants for river bank restoration also have been completed.
The dams will be torn down at the same time.
While the contractor will decide how the dams will be torn down, Winter said, the park envisions Lake Mills being lowered to up to 80 feet to allow flood protection while work proceeds on the Elwha Dam.
Glines would be notched on alternating sides to create temporary spillways, with layers of the dam removed before the remaining bottom portion is blasted.
The Elwha Dam’s reservoir would be lowered by about 15 feet, with coffer dams and a diversion channel directing the reservoir’s outflow.
Then the dam and the powerhouse would be removed — the contractor will own the powerhouse along with its giant turbines — and the site revegetated.
Still yet to be determined, though, is the route that countless trucks will take when carting off the dams’ remains, piece by piece by piece.
Access roads to both dams are narrow, and winding.
Glines Canyon Dam is at the end of two-lane Olympic Hot Springs Road and about six miles from U.S. Highway 101.
The popular Elwha and Altair campgrounds are off Olympic Hot Springs Road, as is Whiskey Bend Trail.
Elwha Dam is at the end of Lower Dam Road, a shorter, even narrower road that’s off state Highway 112 and is barely wide enough for two vehicles to sit side-by-side, much less a single large dump truck.
Lower Dam Road is the shorter and narrower of the two.
In its entirely, this is the largest dam removal project to date in the nation’s history and the second largest restoration project ever conducted by the Park Service next to a similar effort conducted on the Florida Everglades.
In a 2006 article describing the dams’ decommissioning, Popular Mechanics magazine called this the largest dam removal project in the world, as has Peninsula College’s Center of Excellence, which has conducted research on the river restoration project.
The pending removal of four dams on the Klamath River in Oregon will be even larger, though not as expensive, at about $75 million to $175 million, according to American Rivers, a Washington, D.C.-based river conservancy organization.
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Senior Staff Writer Paul Gottlieb can be reached at 360-417-3536 or at paul.gottlieb@peninsuladailynews.com.
