Potter Valley Irrigation District Logo

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
Meeting flyer for January 10, 2018, Potter Valley School Multipurpose room, 6pm.
Meeting flyer

Potter Valley Project Relicensing

In order to continue operating Lake Pillsbury, Scott Dam, and Van Arsdale Dam, along with the diversion that runs the Potter Valley Project 9.4 MW hydropower plant and provides water to the Potter Valley Irrigation district past 2022, Pacific Gas and Electric Company (PG&E) must obtain a new FERC license. At the current time PG&E is not proposing to add capacity or make any major modifications to the Project or its operation. The initial documents have been submitted and the process is underway. The Potter Valley Project is a critical water resource for Potter Valley.

A new group has formed, Water Solutions, that is closely following the relicensing process and the impacts of it on the Eel River and Russian River watersheds. You can sign up with them to get email updates with news about the relicensing, including updates on public comment periods.

On January 10, 2018, at 6pm in the Potter Valley School multipurpose room, the PVID Board will be hosting a public presentation detailing the project, the relicensing process, and how you can help. There will be opportunities for questions, and refreshments will be provided.

Documents relating to the process, including presentations shown at the March 2017 public meeting, can be found at http://www.pge.com/pottervalley. You can also find instructions there to be notified by email of FERC activity on this project, and this overview of the project that includes many historical and contextual images of the Project.

Scoping Document #2, which lists issues to be considered in the Environmental Impact Report, is now available. Read more on the Potter Valley Project Relicensing page.

Featured Documents

Check out our 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 Economic Impacts of Water and Agricultural Industries: Inland Mendocino County - 2015 study documenting the economic value of water and water storage in the Upper Russian River watershed.
Memorandum: Dependable Yield for Coyote Valley Dam (Lake Mendocino) - UC Davis memo discussing water management for Lake Mendocino under drought conditions.

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.

Busch Creek Flume, Jan 10, 2017
Busch Creek Flume, Jan 10, 2017

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