Proposed Article


Almanor Fishing Association Newsletter


Bill Dennison


“Is The Thermal Curtain Dead?’


What Is A Thermal Curtain?


Before this brief article can be meaningful, it is necessary that the reader understand the term “Thermal Curtain”. (TC).

Thermal Curtains are large devises that have been installed in various lakes, much deeper than Lake Almanor and Butt Reservoir to remove cold water from the lower lake levels and distribute that water downstream for the enhancement of those fisheries and to reportedly “..reduce the stress to fish….”

Who Initiated the TC Concept For Lake Almanor?


TC’s were recommended by the collaborative group that developed the proposed re-licensing of Federal Energy Regulatory Commission (FERC)  Project #1962, Rock Creek/Cresta  (RC/C) four years ago. This proposal was accepted by FERC as a potential option to reducing the water temperature at the RC/C reaches, about 25 miles south of Lake Almanor. The Rock Creek/Cresta license was granted to PG&E on the basis that the utility company would attempt to reduce the water temperatures to 20 degrees Celsius, or lower through installation of a TC, or other procedures during the application for Lake Almanor FERC License #2105.


Why Are TC’s Now An Issue?


Since the issuance of the RC/C license, FERC has initiated the re-licensing of the next hydroelectric project that will terminate in October, 2005; Project # 2105, Lake Almanor. This includes Butt Reservoir and all of the hydroelectric facilities down to Belden.  The 2105 Committee, which I chair was appointed by the Plumas County Board of Supervisors to lead the way in developing a collaborative. We helped implement 2105 Licensing Group (LG) that over the past 2 ˝ years reached agreement on many  aspects of the Lake Almanor project (water level, water quality, stream flows, recreation facilities, etc.). This agreement was signed April 23, 2004.  However, PG&E did not provide all of the water temperature data regarding the installation of TC’s in Lake Almanor and Butt Reservoir, until October and even then, not all of the material was understandable.


As the data were revealed, the proposal changed from one TC in Lake Almanor for a cost of  $13-15 million to two more TC’s in Butt Reservoir with a total price tag of over $50 million for PG&E Rate Payers to absorb.


Then, we learned that the water temperature reductions at the RC/C reaches would be less than 2 degrees Celsius and based on available, historic water volumes this reduction in water temperature would only be viable about 50% of the time.


Next, we found that PG&E anticipated the removal of up to 50% of the cold water from Lake Almanor and studies indicate that this would cause a reduction in cold-water habitat. Because, degradation to Lake Almanor fisheries to improve water temperatures downstream is not acceptable we voiced opposition to the proposed TC construction.


Options to TC’s were proposed by PG&E, but quickly ruled by them as not feasible, due to high costs and/or engineering difficulties. It appeared to some that TC’s would be chosen by State Water Resource Control Board (SWRCB), because of the lack of proposed options.


Members of the 2105 Committee and experts, including retired Dept. of Fish and Game fish biologist Ron DeCoto and game warden Bob Orange, along with local fishing experts, some of whom are AFA members understood the degradation to the fish and lake ecology of withdrawing large amounts of cold water from Lake Almanor. Opposition was raised continually during the 2105 LG meetings and other forums. 


A Battle Cry—“Stop The Thermal Curtain” Was Heard.


Just prior to the November, 2004 FERC Public Meetings a very effective grass roots movement (of which AFA was a strong voice) was initiated in the Lake Almanor Basin. The battle-cry to “Stop The Thermal Curtain” and “Save Our Lake” was heard, not only in Plumas and Lassen Counties, but throughout the State of California and beyond. Our political leaders, Congressmen John Doolittle and Wally Herger, Senator Dianne Feinstein, State Assemblymen Rick Keene and Doug LaMalfa and State Senator Sam Aanestad received hundreds of letters that alerted them to the seriousness of the TC proposals.


Subsequently, there was a large attendance at both the Chester and Chico public meetings held by FERC to review the Draft EIR on the Project #2105 Re-licensing Application. FERC representatives avowed that since TC’s had not been officially proposed it was too early to include testimony against the structures. However, testimony by citizens and representatives of all of the elected officials noted above, except for Senator Feinstein’s office did testify against any further consideration of TC’s in either Lake Almanor, or Butt Reservoir.


Has PG&E Spoken?


In November, 2005, PG&E issued a press release that confused some into believing that we had won the battle to “Stop The Thermal Curtain.” I suggest that this is not true. PG&E “had spoken”……….very timidly.

 PG&E’s very constrained public statement required several weeks of internal editing and included the following exerpts:


“PG&E has clearly heard the communities request that PG&E comment on the prospects of a floating thermal curtain in Lake Almanor. Based on studies and information to date, PG&E does not anticipate recommending a floating curtain in Lake Almanor as a reasonable measure for reducing downstream water temperatures ..…” (emphasis added).

     (Editorial note: Conversations with PG&E representatives have not provided anymore clarity than can be read into the words that I have underlined—Thus, we can assume that we have not seen all of the studies and information, but new data could negate the lack of “anticipation” to recommend the TC’s. A minor consideration, is that the statement only speaks of the “floating curtain”, not other means of removing large portions of cold water from Lake Almanor. (e.g. water releases from Canyon Dam)


The press release continued,

Studies and information to date indicate a floating thermal curtain in Lake Almanor:

·        Is technically feasible     

(Editorial note---“technically feasible” means that the TC’s can be constructed. We have never contested the engineering potential for construction, only the resulting negative impact on the local fisheries and damage to the Maidu Tribe cultural sites and burial grounds.

·        Would reduce water temperatures in the Rock Creek Cresta reaches……to 1 to 2 degrees Celsius. 

(Editorial note---Based on data available, mention of 2 degrees reduction is a stretch of facts; data in general indicate less than that in RC/C. In addition, as noted  above, PG&E did not tell the entire story---based on 50 years of historic water data, this reduction of temperature would only be available about 50% of the time. During the other years, the fish would continue to be “stressed.”

·        Would reduce coldwater habitat in Lake Almanor and fish production in Butt Valley Reservoir. 

(Editorial note—This is true, but in addition, we believe that the coldwater reduction would also cause significant degradation to the lake’s ecology, such as an increase in the algae and weeds and reduce the desirability for water sports).

·        Is strongly opposed by Lake Almanor area residents. 

(Editorial note---PG&E got this one right, but everyone, including FERC must be reminded that the opposition extends far beyond local residents. In fact, there have been letters of opposition from outside of California and one from Europe!) In addition, there was no mention of the Maidu Tribe protests of the potential decimation of their Prattville cultural sites during the proposed construction of the TC.)

·        Would be very costly for the benefits achieved.

(Editorial note---Again, this is very correct and will generate even more opposition to any future consideration of the TC when PG&E customers learn that they would have to pay the bill.)


PG&E has spoken and their news release was appreciated, because Plumas County and 2105 Committee and several within the 2105 LG believe that no more time should be wasted on further discussion of the TC’s. But, that conclusion and support can not be drawn from the news release.


As written in the “Editorial notes” above, I suggest that we should not believe that the press release strikes any “death knell” to the TC. Thermal Curtains and all other options for reducing the water temperatures at RC/C will be reviewed by SWRCB and thus far the SWRCB staff comment has been “…PG&E is entitled to their opinion…”

We cannot assume that SWRCB will accept, or reject the TC’s as a viable option. Therefore, continual vigilance will be necessary for the next 12 to 18 months, or until the final Project 2105 License is signed by FERC.


Next Steps?


Plumas County Board of Supervisors (Board) fully supports the guidance and work of the 2105 Committee. The Board

expect’s the 2105 Committee to report periodically and to seek assistance as necessary to be assured that the goals set forth in last years Plumas County Resolution are met. Thus, the 2105 Committee will not accept the TC’s as viable options to the water temperature issue.


The 2105 Committee members are continuing to meet with the 2105 LG (PG&E, F.S., DF&G, SWRCB, White Water groups, US Fish and Wildlife Service and Fishing Associations) to review every potential option to the Thermal Curtain. Those options are displayed on our website   In addition, our web manager Bob Lambert, also adds the most recent information about scheduled meetings and meeting notes to the site.


 We must look to those who initiated and implemented the grass roots movement, commonly referred to

as  “Stop The Thermal Curtain” and “Save Our Lake” for continued support. You can depend on us first, pursuing your   interests during every meeting in which we represent you. And, finally I will keep you informed of how you can continue to take an active part in this important issue.


In between the times that I may provide information through the local newspaper, or other public forums, you may find my Local Email Newsletter helpful on Lake Almanor and other County issues.  To be added to the LENL, just contact me at .


Another great place to stay current on the TC issue is through the grassroots website Wendi Durkin and Dale Knutsen combine talents to maintain that important site.


In summary, the Thermal Curtain is not yet dead, the truths about it have slowed it’s momentum. The Thermal Curtain is no longer accepted by most people as the solution to the water temperature issue. Most important, is the fact that issuance of the PG&E statement and the high support of all our elected officials resulted from sincere efforts of AFA and others  who contributed time and finances to “Stop The Curtain” grass roots movement.


As always, “Truth Will Prevail”, but it takes participation.


My personal thanks to everyone who has been involved and to those that will join the coalition in the future.


Please let me know if you have questions.