Big rigs ripping out concrete
A $6,000-a day hydraulic shear chewed through iron rebar and a hoe ram punched holes in concrete that held back the Rogue River for 88 years, as demolition of one side of Savage Rapids Dam entered full swing Tuesday morning.
“We could probably be done next week,” said Darren Funk, project manager for Slayden Construction.
Last week, Slayden tore out one of six bays on the north side to drain water and remove sediment from behind the dam, Funk said.
Tuesday, the giant hammer and two metal jaws worked together to rip out the concrete on the remaining five bays on the north side.
The dam, which should be gone by December, was already replaced by huge pumps this year to serve about 7,000 customers in the Grants Pass Irrigation District.
The nearly $40 million project is the culmination of a long battle between the government, the district and environmental groups over protecting Rogue River salmon and steelhead. The dam’s fish ladders never met federal standards, and biologists estimated thousands of fish were affected by poor passage.
GPID upgraded other potential fish killers such as pumping turbines over the years, but agreed in 2001 to remove the dam, in exchange for the end of litigation.
“When a person’s involved in something like this for so many years, it’s almost anti-climactic,” said Dan Shepard, manager of the GPID for most of the last 15 years.
The concrete structure looked strange with square holes in it, with the grid-shaped rebar underneath. The large pipe that carried water through the dam to the South Highline Canal was also visible.
Funk said the giant shear, rented from another company, makes the job far easier than just using the hoe ram.
“The reason for using that shear is separating the rebar from the concrete,” Funk said. “If you just used the hoe ram, you’d have a lot more mess to remove.”
Removal of bays on the south side will have to wait until October, when Slayden breaches a temporary cofferdam protecting the northside work. That will allow the river to run freely through the section for the first time in nearly 90 years.
A smaller cofferdam will be built and the south end of the dam is scheduled to come out in December.
The far north and south ends of the dam will be left in place, including what’s left of the former pumping station on the north side.
Slayden will fill holes and make the structure safe.