Water issues at Lake Almanor attract regional noticeBy Bruce Ajari
North Lake Tahoe Bonanza
As everyone is well aware, water is becoming a highly sought-after commodity. It is crucial to our local fisheries. With Lake Tahoe soon to drop below its natural rim for a second time, we all know what the Truckee River is looking like these days.
A recent trip north to Lake Almanor exposed me to a huge water issue that the local community is facing up there.
As part of a dam's Federal Energy Regulatory Commission re-licensing plan for Lake Almanor, the State Water Quality Control Board is requiring consideration for lowering the temperature of the North Fork of the Feather River about 40 miles downstream between Rock Creek and Cresta dams.
A water temperature of 68 degrees (20 degrees Celsius) is being sought during the summer months as part of the plan. This is to enhance water temperatures for trout.
Installing a thermal curtain in Lake Almanor and additional ones in Butt Valley Reservoir is apparently the recommended approach for achieving this temperature decline by removing water from the lake's bottom.
The concern is that the thermal curtain would remove a considerable amount of the coldest water in both lakes. The Save Lake Almanor citizens groups estimates that cold water diversion could be as high as 40 percent of the entire cold-water layer (hypolimnion) in the lake.
The most effective thermal curtain configuration is U-shaped, 900 feet by 770 feet by 900 feet. The most effective elevation of the curtain bottom is 4,455 feet (USGS datum). This configuration (without dredging of the Prattville Intake area) provides about 4.4 degrees Celsius and 3.6 degrees Celsius water temperature reduction at the Butt Valley powerhouse during July and August, respectively, at its normal operating discharge of 1,600 cubic feet per second.
The Save Lake Almanor committee feels that cold water removal could increase algae blooms and dramatically impact the existing Lake Almanor trout fishery. They also feel the dredging could disturb ancient Indian (Maidu) burial sites.
It is certainly a battle that bears close watching to see what the State Water Quality Control Board does with this plan. You can view just what is going on with this project at savelakealmanor.org. The information on the project itself can be viewed at nsrprojects.com.
The fishery at Lake Almanor is a great one by all accounts, and risking that for a plan to create habitat that does not presently exist seems quite a risk to take, particularly if you are in the impacted communities around Lake Almanor.
We have seen how much a local economy can suffer with the chemical treatments of Davis Lake in the Portola area. A repeat of this in the Almanor area would be catastrophic. The communities depend on this fishery.
Bruce Ajari is a Truckee resident and regular fishing columnist for the North Lake Tahoe Bonanza and other area newspapers.
david griggs Sunday, 06 July 2014
lake almanor has every right to protect its nature and resourses