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It's all about the salmon

The city of Medford will start restoring stream-cooling riparian zones along the Rogue River and its tributaries to offset the warm water released from its wastewater treatment plant under a new operating permit touted as a way to go green while saving some green.

In the first program of its kind in the Rogue Valley, state and federal environmental officials have approved a new operating permit and thermal-credit trading for the city's Regional Water Reclamation plant.

Over the next two decades, the city will pay to rehabilitate and enhance 38 miles of riparian lands to more than make up for the treated effluent that is too warm for wild salmon needs when it is released into the Rogue off Kirtland Road near TouVelle State Park.

These new projects must be proven to cool the basin's water, must be verified as effective by a neutral third party and be maintained for up to 20 years.

The estimated $8.3 million plan was chosen as an alternative to adding two large mechanical "chillers" to cool the effluent to required levels. That option was estimated to cost the city about $15 million, but not improve habitat while emitting greenhouse gases while in operation.

The DEQ formally approved the permit Monday, after one final review by the federal Environmental Protection Agency.

The tradeoff of cooling the basin to offset the warming effluent "was the big different thing" the EPA was evaluating, "and they were OK with it," said Cory Crebbin, manager of the city's public works department. "When it came out of that, we were very pleased."

The city last week also hired the Portland-based Fresh Water Trust to administer the program.

The riparian projects will be done on private lands on southern stream banks to take maximum advantage of shade production.

David Primozich, the trust's director of ecosystem services, said the trust already has started meeting with local watershed councils and stream-restoration professionals who will be hired to do the actual riparian work.

The group soon will start seeking out landowners who will participate in the program, Primozich said.

The first riparian projects should be done by next December, Primozich said.

The Medford plant releases up to 20 million gallons of treated water per day into the Rogue at river mile 130.5 just downstream from TouVelle State Park. The new DEQ standard allows the treated effluent to raise the river's temperature by a fraction of 1 degree Celsius, and the plant's configuration cannot achieve that during low-flow periods in the fall, with mid-October the worst.

Patterned after a similar pilot project along the Tualatin River in 2004, this program is the first created under the state's new and more rigid rules about creating such mitigation programs — many of which carried no maintenance requirements in the past.

The city of Ashland is putting together a similar program for a new permit to operate its water-treatment plant in the Bear Creek Basin, a major Rogue sub-basin.

As water-treatment plants in the basin come up for new operating permits, the DEQ is systematically setting lower temperature targets for the rerleases of treated effluent. The reason is how warmer-than-natural water affects incubating chinook salmon eggs in gravel nests, called redds, through fall and winter.

Water temperatures dictate how fast the eggs incubate. If they incubate too quickly from warmer water, they hatch too early into the Rogue when food availability for them is low.

Reach reporter Mark Freeman at 541-776-4470, or e-mail at mfreeman@mailtribune.com.