I love this story. Dams certainly have their place but they can be overbuilt also. This is certainly a situation were the removal is obviously well justified.
A dam has one proper purpose. It is called flood control. When that is not a particular issue, energy can be collected through run of the river hydro facilities and well located dams with a working fish bypass system in place. In fact I have posted on a horizontal turbine system that while not producing a lot of power will allow returning salmon to climb through the system back up to the top of the reservoir.
Once again, I would be willing to take on the contract.
We are not going to give up the Aswan or the Yangtze River dams anytime soon. The flood control aspect is often as important as the power generation if not more so. In time though, we may decide that we need to build more flexibility into even flood control.
For example the Nile could be diverted into a second channel west of the present course and filling the Qattara Depression . This could be done with diversion channels and a barrage allowing a switching back and forth of the flow of the Nile . Done properly far to the south the Aswan could be retained for some time and possibly have its natural lifespan extended while much silt is used in the new channel and its related new farmlands.
In time, the Aswan
This project is going to inform us a great deal over how difficult it is to fully restore a rich river. We need that knowledge. The Columbia
Officials hope dams' removal will bring the big salmon back
By Les Blumenthal | McClatchy Newspapers
Up until a century ago, they returned annually to the Elwha River on Washington
Then, two dams were built across the river, .and the spawning grounds were blocked, giving the fish less than five miles of river to breed. Today fewer than 3,000 fish return to the Elwha.
That's about to change.
In what would be the largest dam removal project ever in the United States
The dams won't be blown up, but dismantled over roughly three years so the 19 million cubic yards of silt, gravel and rock behind them can be flushed downstream gradually.
The project will cost more than $300 million. The cost of removing the dams _ $60 million to $70 million _ is only a portion of the price tag.
Once the dams are down, it may take 10 years to re-establish the runs, but officials are determined that the fish will return. Some will be flown by helicopter to the upper reaches of the Elwha watershed. To supplement the meager number of native fish, others will be raised in a nearby hatchery and added to the runs. Eventually, the runs are expected to become wild.
Scientists say if the salmon runs can't be restored on the Elwha, they can't be restored anywhere.
More than 85 percent of the river's salmon habitat is in the Olympic National Park, remote back country even now barely touched by man.
"I have no doubt this will work," said Brian Winter, the Elwha Project manager for the National Park Service.
Winter, a fisheries biologist who's been working on restoring the Elwha runs since 1985, said the river is a living laboratory that has been studied for decades.
"This isn't so much about taking out the dams, it's about seeing the first salmon headed up stream," he said.
Others are calling it the "last dam summer" as demolition work is expected to begin next year.
"All eyes, including internationally, are on it to see how a river comes back to life," said Amy Kober of American Rivers. "The lessons we learn on the Elwha will apply to others rivers around the nation."
To the Lower Elwha Klallam Tribe, the removal of the dams is about more than salmon. When the dams were built, the reservoirs that grew behind them flooded the tribe's only inland village and the "tribal creation site," where according to legend the tribe was created.
"We just have word of mouth about where they are," said Robert Elofson, the tribe's director of Elwha River
The dam removal project began in 1992 when Congress approved the Elwha River Restoration Act.
The privately owned dams provided electricity that helped power the economy of the Olympic Peninsula, including the Bremerton Naval Shipyard and nearby paper mills.
There were several attempts to strip funding over the years, but they failed. Former U.S. Sen. Slade Gorton, R-Wash., unsuccessfully sought to link the Elwha project to a promise that four dams on the lower Snake River would never be breached to aid salmon runs in the Columbia River basin
Before seeking bids to remove the dams, the Interior Department, which includes the National Park Service, spent $24.5 million on a water treatment plant for the city of Port Angeles Port Angeles
The Interior Department also paid $16.4 million to construct a new tribal fish hatchery. Work is also underway on some levy modifications.
Congress has been providing roughly $20 million in funding annually and nearly $55 million in economic stimulus money was also appropriated.
Rep. Norm Dicks, D-Wash., whose congressional district includes the Elwha, has championed the project from the beginning.
"There's no question we can do this," Dicks said of restoring the runs.
Dicks is an avid fisherman. In his congressional office is a mounted 54-pound salmon he caught in Alaska
No one is betting those giants will return to the Elwha.
But to those who have been working on the restoration project for 18 or more years, the end may be in sight.
"It's amazing we are so close," said Kober. MORE FROM MCCLATCHY
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