Sediment tests aid removal of Gold Ray Dam
GOLD HILL — Efforts to remove Gold Ray Dam from the Rogue River took a leap forward this week when preliminary results showed no troublesome levels of contaminants in the sediment behind the structure.
In a report expected to reach Jackson County officials early next week, sediment tests reveal the presence of little or insignificant amounts of heavy metals, pesticides, mercury and other contaminants trapped behind the 105-year-old dam.
The presence of contaminants at higher levels could have meant that some or all of the sediment would have to be removed before the dam could be breached.
“We haven’t found anything that would cause a big problem with this project,” said John Vial, the county’s roads and parks manager who is overseeing the effort into whether the dam should be removed.
“It’s a big step,” Vial said.
Also, tests reveal that most of the sediment behind the dam is a mixture of sand, gravel and cobbles similar to that found behind Savage Rapids Dam and the Gold Hill diversion dam.
That opens the door for a so-called “blow and go” plan that would allow the sediment to travel downstream on its own during freshets instead of relying on mechanical removal.
“If it was pure clay, silt and mud, that could have been a big problem,” Vial said. “But it’s not.”
Vial said he expects to receive a preliminary written report on the findings early next week.
The findings may boost impetus toward removing the last concrete impediment over 157 miles of the Rogue between Cole Rivers Hatchery and the Pacific.
Jackson County commissioners have yet to vote on whether to remove the dam, which fell to county hands after it was decommissioned as a hydropower facility 37 years ago.
Studies estimated that 400,000 cubic yards of sediment is under water and backed up by the 38-foot dam.
The sediment studies were required by the U.S. Army Corps of Engineers, which oversees sediment issues involving dam-removal projects.
The county has a $5 million federal stimulus grant to study and remove the dam by the end of 2010, and Jackson County is awaiting a Aug. 21 deadline for receiving sealed bids from contractors interested in the project.
About 80 people attended a pre-bid meeting Tuesday required by the county for firms that bid on the project, Vial said. The session was held to describe in detail the county’s proposal, leading to what Vial called a “very good question-and-answer session.”
After the bids are accumulated, county officials expect to evaluate and score them, then conduct follow-up correspondence with the top bidders, Vial said.
“There appears to be things coming together that look real promising,” Vial said. “But we’re not there yet.”
Vial said he expects a contract for environmental study, design and removal of the dam to come no sooner than mid-September.
While county officials are still two weeks away from opening potential bids, already outside players are looking to line up more money for the project should bids exceed $5 million.
Officials at the Oregon Watershed Enhancement Board — which has helped pay for removal of the Gold Hill diversion dam and the ongoing removal of Savage Rapids Dam near the city of Rogue River — have kept an eye on the Gold Ray Dam project.
OWEB Deputy Director Ken Bierly said there is a “real likelihood” that a specific grant request for this project will come to OWEB once Jackson County determines whether and how much extra money is needed for dam removal.
“It’s an important project for the Rogue Basin,” Bierly said. “We’re going to work with the county to make sure they don’t lose $5 million in federal funds.”
Jackson County Administrator Danny Jordan said NOAA-Fisheries also could be another source for additional money should that be necessary.
“We’ll all be scrambling to find funds, with OWEB and NOAA-Fisheries possible sources,” Jordan said.