The Clackamas River is fish bearing stream about to see big changes. It is near the city of Portland, Oregon and flows through communities like, Oregon City, Gladstone, Estacada, Barton and Carver among others. Spring and fall Chinook salmon, coho, winter-spring and summer Steelhead run in it's waters. Flowing off the cool slopes of the Mt. Hood the Clackamas River is a complex system with a number of power generation projects interupting it's flow. PGE operates with-in the Clackamas basin and is up for relicensing it's current project. For relicensing PGE has been tasked with some major changes to the way business is done.
Warm water temperatures are death to salmon & steelhead juveniles as well as resident trout. The Clackamas river has been exceeding the maximum temperature requirements during summer months. PGE's solutions to lowering the water temperatures are big moves that in theory will improve the health of the river system.
North Fork Dam on the Clackamas River
First, adding spawning size gravel to the system below River Mill Dam is supposed to help the water run faster and cooler. Thousands of yards of gravel are expected to be added to the river. More water will be below the riverbed surface and under and around rocks gaurding it from the sun. This also mitigates for lack of spawning size gravel moving through the river system from upriver tributarys. The dams stop this movement of important sized gravel and over the years this is having a cumulative effect. Less spawning gravel for wild fish.
Fish Trap below Casadero Dam on the Clackamas River- Spring Chinook in the water
Second, Faraday lake on the Clackamas river system is a diverted portion of the river split apart at Casadero Dam. This water historically sat in the lake and then is run through power generation exiting back into the main river channel. This is also beleived to be a culprit of warmer water temperatures in the lower river during the summer months. The current plan calls for eliminating the lake and channelizing the water to the power generation facility.Third, new fish trap facilities are planned to be state of the art and reduce fish handling. A new facility is being built near North Fork reservior. This new facility is promised to be much better than the old facility below Casadero Dam.
Fourth, new juvenile collection traps will be placed at the top of Rivermill and North Fork dams. Funneling fish into the newly updated bypass tube that takes downstream migrating fish from above NF all the way to below Rivermill dam.
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