Jackson County officials this summer plan to start laying the foundation for deciding whether to notch or remove Gold Ray Dam and create a free-flowing Rogue River from Lost Creek Lake to the sea for salmon and boats.

Jackson County officials this summer plan to start laying the foundation for deciding whether to notch or remove Gold Ray Dam and create a free-flowing Rogue River from Lost Creek Lake to the sea for salmon and boats.

County officials this week received word that they won a $100,000 grant to complete a study of the amount and contents of the muck that has accumulated behind the 35-foot-tall dam since the first version of it spanned the Rogue near Gold Hill more than a century ago.

Analysis of the upstream sediments is a necessary precursor to removing or notching the dam, a former power-generation dam decommissioned more than 35 years ago.

The dam is considered an impediment to salmon and steelhead migration.

It's also considered a liability to Jackson County, which took over ownership of the dam and its adjacent 29 acres in 1972 for development of a park.

The Oregon Department of Fish and Wildlife considers removal or improvements of Gold Ray Dam to be the fifth-highest priority for fish-passage improvement of all barriers in all of Oregon's streams.

With the removal of Savage Rapids Dam and the Gold Hill diversion dam already in the works, eventual removal or notching Gold Ray Dam would mean 157 miles of free-flowing Rogue passable to salmon and boats.

"We're been wanting to do something for years, but funding hasn't been there," said Lin Bernhardt, the county's natural resources manager. "Now, for fish-passage reasons, the priorities have increased and the attention has increased.

"It's doing absolutely no good. In fact, it's doing lots of harm," Bernhardt said. "We need to figure out how to deal with those issues."

But first, county officials must figure out what's backed up behind the concrete span.

Possibilities run the gamut from fine silt to gravels, cobbles, heavy metals, organic materials or any combination thereof.

"There's a lot of sediment there, but nobody know what it is," said Steve Mason, whose firm DHR Engineering is already working on a pre-feasibility study on the dam. "But before you deal with it, you have to determine what's there."

In fact, it could literally be a gold mine.

"There is the possibility that there could be value in there," Mason said. "With all the gold mining up there, there might be some gold in there to help pay for it.

"There's 100 years of history behind that dam," Mason said. "This should be interesting."

Once Savage Rapids Dam and the Gold Hill diversion dam are removed, Gold Ray Dam will remain the largest artificial impediment to six runs of anadromous fish that pass the site and into 333 miles of upstream spawning habitat.

Set to be finished by December 2009, the sediment study will cost an estimated $143,000.

The lion's share will come from NOAA-Fisheries through Ecotrust, a Portland-based nonprofit organization that received $400,000 of federal money for community-based habitat-restoration projects.

Of that, $100,000 was earmarked for a dam-removal project, said Brent Davies, Ecotrust's director of forestry. Jackson County's Gold Ray Dam proposal earned that grant, Davies said.

"We think the Rogue Basin is an important place," Davies said. "It's one of the high-priority areas for whole watershed restoration."

The remaining money for the study will be covered through in-kind donations, most of which will be staff time, Bernhardt said.

While notching or removing the dam are considered the county's preferred solutions, those are not foregone conclusions.

Sediment tests could show that the amount of material backed up by the dam and the potential presence of pesticides, mercury or other dangerous materials could point toward buttressing the aged concrete and improving fish ladders as better solutions.

No estimated cost or timetable for future work, including environmental studies, has been set, Bernhardt said.

Reach reporter Mark Freeman at 776-4470, or e-mail mfreeman@mailtribune.com.