By Bill Sheets, The Herald
INDEX — A controversial plan to build a mini-dam on a scenic stretch of the South Fork Skykomish River might become a little less controversial — at least from the point of view of the utility hoping to do the project.
Officials of the Snohomish County Public Utility District now say they can build the project near here without having a structure partially block and divert water — that enough water can be collected in a sharp bend in the river to be sent through a tunnel to a powerhouse downstream.
The previous plan called for pooling water behind a 7-foot, inflatable weir on the river above Sunset Falls before sending it through the 2,200-foot tunnel.
Removing the weir from the Sunset Falls project addresses aesthetic concerns, reduces construction time and cuts $10 million off the project, previously pegged at $133 million, according to the PUD.
“Visually, you really won’t see much,” spokesman Neil Neroutsos said. “Some times of the year, portions of the very top of the intake may be visible.”
One opponent says eliminating the weir wouldn’t help much.
“The bottom line is, if you’re going to produce hydropower in this river, you have to divert enough water form the river’s natural course and channel it to the turbines to make the hydropower. Any significant amount of hydropower you could create would affect salmon habitat,” said Andrea Matzke, who has a cabin near the proposed dam site.
The Tulalip Tribes have expressed concern that reducing water flow in the river could impede outward migration of juvenile salmon. That issue will be studied this spring, PUD officials say.
Nearby residents and environmental groups have opposed the project. They have also cited the fact that rock blasting will be necessary to build the tunnel, contending it could create dust, pollute the river and destabilize the terrain. Studies are expected to address these issues as well.
The new design also includes changes to the tunnel, Neroutsos said, making it narrower in places and reducing the amount of excavation necessary.
The utility has not formally applied with the Federal Energy Regulatory Commission to build the project but has submitted preliminary plans. The PUD is to discuss the new plan with the federal agency over the next couple of weeks, Neroutsos said.
The PUD buys more than 80 percent of its power from the Bonneville Power Administration and is looking to diversify power sources. The project could power up to 22,500 homes at maximum output, according to the PUD. The utility also recently received the go-ahead from FERC for a $26 million pilot project to install tidal power turbines in Admiralty Inlet.
More studies, 17 in all, lie ahead on the Sunset Falls project, and any decision is likely five years away, FERC officials have said.
In May, the PUD is planning to survey ratepayers about the project through its website.