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Supporting sustainable food, power, and water for over 100 years

In 1908, a hydroelectric plant was built on the north end of Potter Valley, replacing a coal-fired plant to power the city of Ukiah. Today, roughly 3% of the Eel River watershed is diverted to the Russian River to run the turbines.

Potter Valley Irrigation District provides agricultural water for Potter Valley, in Mendocino County, California, using a portion of the water diverted through the power plant. Potter Valley's family farms produce wine grapes, pears, grass-fed cattle, sheep and other agricultural products valued at over $34 million.

cattle crossingThe Great Green Pumpkin
Pear Trees in Potter Valley, April 2015
Pear Trees in Potter Valley, April 2015

Potter Valley Irrigation District water status update

June 20, 2015

Dear PVID Water Customer,

The recently formed Potter Valley Drought Working Group, whose members are Pacific Gas & Electric Company, National Marine Fisheries Service, California Department of Fish and Wildlife, Round Valley Indian Tribes, Sonoma County Water Agency, Friends of the Eel River and Potter Valley Irrigation District, have been meeting every two weeks to discuss the monthly target storage levels in Lake Pillsbury.

Our efforts to hold all releases from Scott Dam at Lake Pillsbury to the Dry year classification instead of normal have been successful so far in meeting the target storage levels and we will see the current flow rates continue at least until August 1st. Those target storage levels are listed below.

JULY 1st ------- 26,000 AF AUGUST 1st ---- 22,000 AF SEPTEMBER 1st -------- 18,000 AF OCTOBER 1st ---14,000 AF NOVEMBER 1st -12,000 AF

The Dry Year flow rates are determined by the FERC license and are, in large part, flows required by the National Marine Fisheries Service to protect habitat. Currently the total flows required for release below Cape Horn Dam are 12 cubic feet per second (cfs) and 77 cfs through the Potter Valley Powerhouse for PVID and the East Branch Russian River. Total releases from Lake Pillsbury are now approximately 89 cfs or about 180 acre feet (AF) per day. If we stay below 200 AF use per day from Lake Pillsbury for the remaining 102 days to October 1, 2015, it will require approximately 20,400 AF. As of June 20, 2015 there was 31,360 AF of storage in the lake. PG&E has set a minimum pool of 10,000 AF to protect the outlet and service structure at Scott Dam at Lake Pillsbury. At the current release rate, and if it doesn't rain, only 1,000 AF would be available in Lake Pillsbury above the 10,000 AF minimum pool after October 1st to meet the remaining minimum flows required below Cape Horn Dam at Van Arsdale Reservoir, and East Branch Russian River.

Because of this, further reductions in the diversion rates through the Potter Valley Project may be required. This would further reduce the amount of water available to PVID. During a normal water year PVID would be able to use 70-75 cfs during periods of peak demand resulting in a rotational delivery to customers of 10 to 12 days. This year, due to the drought reduced flows, we have been averaging 60 cfs which has increased our delivery rotation to between 14 and 16 days. It now appears that this delivery interval may be extended out to 18 or 20 days during August and September.

We will report any further reductions to the diversion flows if this becomes necessary. Please check the PVID website at www.pottervalleywater.org.

Please monitor your water closely, and use only what is absolutely necessary.

Kenneth Stroh,
President of the Board
Potter Valley Irrigation District

Water Year Reclassified as Dry

Due to the present drought situation, PVID has been in communication with Pacific Gas & Electric, National Marine Fisheries Service, California Department of Fish & Wildlife, Friends of Eel River, Round Valley Indian Tribe, and Sonoma County Water Agency in an effort to draft a variance proposal to FERC that we hope will go into effect by May 15, 2015. This group of agencies will be known as the Potter Valley Drought Working Group. This action will move the Eel River, and the East Branch Russian River into a dry year classification rather than normal, and help protect the PVID Contract water delivery. Lake Pillsbury storage is in jeopardy of being below 10,000 acre feet (minimum safe pool) by September if we don't conserve now.

The following data will help explain where we are now, and where we hope to be by November 1, 2015.

On May 1, 2014 storage was 68,625 AF and on May 1,2015, one year later, storage was only 42,969 AF

Lake Pillsbury Water Projections, in acre-feet
DateProjected StorageTarget Storage Level
July 1 32,299 26,000
Aug 1 25,857 22,000
Sept 1 19,633 18,000
Oct 1 13,899 14,000
Nov 1 10,000 12,000

The Variance flows if approved by FERC at the Dry Year releases in Cubic Feet/Second:

E-11= Below Cape Horn Dam = 9 cfs
E-11 = Buffer flow = 3 cfs
E-16 = EBRR = 25 cfs
E-16 = buffer flow = 3 cfs
E-16 = PVID = 50 cfs

As the summer progresses the Potter Valley Drought Working Group will meet bi-weekly to address storage levels in Lake Pillsbury and consult if target numbers are not being met. These meetings will help determine how to further adjust flows if necessary. FERC will receive monthly progress reports. The drought variance will be in place until Dec 1.

If storage in Lake Pillsbury falls below the target storage level set for each month then it can be expected that reductions in the EBRR flow will be made. This could immediately reduce the amount of water available to PVID by 20 cfs. This would leave PVID with only 50 cfs instead of 75 cfs as is normally needed during periods of peak demand. If this happens, PVID expects to be able to deliver your normal CFS rate but at an extended rotational delivery schedule. This increase in rotational schedule is estimated to extend delivery intervals by 25% to 30% longer. PVID will notify everyone if this change is required.

Please remember, we are in a drought of record. PVID Bylaws must, and will be, strictly enforced.

Chronic and excessive tail water running off your field will be grounds for termination of water delivery. The Board of Directors will be the final authority in this matter. Remember, while water is running off your field it is considered wasting water, and there will be other customers waiting for it!

Please, feel free to contact one of our Directors or the Superintendent with any questions. Printable PDF version

Water Rate Increase

The contract price that Potter Valley Irrigation District (PVID) pays to Pacific Gas and Electric (PG&E) has recently been renegotiated, which will cause a rise in water rates. A letter with the new rates has been sent out to all customers.

New Documents

Check out our new interactive map of the Eel River watershed. It includes major and minor watershed boundaries, USGS stream gauges, popups with pictures and data at points of interest, and major peaks overlaid on a satellite image.

The PVID Documents & Data page collects scientific papers, government reports, regulatory documents, and other relevant data and information for the Eel River and Russian River systems. In some cases, we have scanned or acquired papers that were not previously available in electronic format to make them available here, such as Kubicek, P.F. 1977., which is a key study of Eel River summer temperatures.

Potter Valley Project 2012 Block Water Releases & Guidelines (12 MB PDF) is from a July 30, 2012 presentation to the Eel-Russian River Commission Meeting by Dick Butler and Jeffery Jahn of NMFS. This is an excellent discussion of the use of Lake Pillsbury block water and considerations used to determine whether proposed water releases are appropriate and beneficial to fish.

Potter Valley Project Block Water Request 2014 - NMFS/CDFW press release discussing their 2014 block water request of 2,085 acre-feet for the purpose of lowering and monitoring the water temperature from Lake Pillsbury to Outlet Creek to protect juvenile steelhead from August 15 through October 11. The release will be closely monitored to determine its effectiveness and also to inform future models of the system.

C. Hypotheses and Effectiveness Monitoring

This blockwater release will test the following hypotheses:

  1. Increased releases from Lake Pillsbury through the Scott Dam needle valve will increase the extent of the optimal coldwater rearing zone (≤ 20°C) between Scott and Cape Horn dams.
  2. Increased releases from Lake Pillsbury through the Scott Dam needle valve will decrease water temperature and increase habitat availability (using flow as indicator) downstream of Cape Horn Dam to Tomki Creek.
  3. Sufficient reservoir storage will sustain a coldwater pool that effectively maintains favorable steelhead temperature-dependent interaction conditions between Scott and Cape Horn dams.

The following data will be gathered to test these hypotheses:

The latest Russian River frost water regulation decision (2.7 MB PDF) was reached on 9/26/12. The State Water Resources Control Board's Section 862 frost water regulation on the Russian River was judged an improper exercise of the Board's authority. The Findings of Fact contains a substantial narrative discussing frost protection in the Russian River watershed and the use of water for this purpose. While these frost water regulations excluded Potter Valley, it is worth reading the narrative to get a better understanding of water issues on the Russian River system.

We've created a new interactive graph of Van Arsdale Fish Counts showing all historical data from VAFS starting in 1933. You can also download the raw data in CSV form, if you wish. The graph makes it easy to compare the counts of the different species and to see how counts have changed over the years.

potter valley panorama