Petition Requesting Approval of a Temporary Urgency Change in Water Right Permits 12947A, 12949, 12950, and 16596 in Mendocino and Sonoma counties

2021010071

Sonoma County Water Agency

NOE - Notice of Exemption

1/8/2021

1/8/2021

The proposed action would occur in Mendocino and Sonoma counties at Lake Mendocino and in the Upper Russian from Coyote Valley Dam/Lake Mendocino to the confluence with Dry Creek.

Jessica Martini-Lamb

Sonoma County Water Agency

Lead/Public Agency

404 Aviation Blvd.
Santa Rosa, CA 95403

(707) 547-1903

Jessica.Martini-Lamb@scwa.ca.gov

Sonoma County Water Agency

Project Applicant

The proposed action would occur in Mendocino and Sonoma counties at Lake Mendocino and in the Upper Russian River from Coyote Valley Dam/Lake Mendocino to the confluence with Dry Creek. Figure 1 shows the streamflow requirements for the Russian River system. Communities and cities along the Russian River include Ukiah, Hopland, Cloverdale, Geyserville, Healdsburg, Forestville, Mirabel Park, Rio Nido, Guerneville, Monte Rio, Duncans Mills, and Jenner.

Categorical Exemption

Section 21080(b)(4) and State CEQA Guidelines 15307, 15308, 15301(i)

The proposed action is statutorily exempt under California Environmental Quality Act (CEQA) Statute 21080(b)(4) and categorically exempt from CEQA under the State CEQA Guidelines Sections 15307, 15308, and 15301(i). A. Actions to Prevent or Mitigate an Emergency California Public Resources Code, Division 13, Section 21080(b)(4) provides that specific actions necessary to prevent or mitigate an emergency are exempt from CEQA. As of January 6, 2021, the water supply storage level in Lake Mendocino was 28,206 acre-feet. This storage level is approximately 41 percent of the available water conservation pool for this time of year. The current low storage level is the result of severely low rainfall in the region. As measured at Ukiah, recorded rainfall for 2020 was 11.32 inches, which amounts to 31% of the average rainfall (37.01 inches) and the second lowest recorded rainfall since 1893. Without significant storm events in the near future, results of the modeling show storage levels in Lake Mendocino well below 20,000 ac-ft by the end of the water year due to releases required to meet downstream water demands and minimum instream flow requirements on the Russian River. Furthermore, it is anticipated that PG&E will file an application for a flow variance for the PVP with the FERC due to extremely low storage levels in Lake Pillsbury and concern that they can no longer meet minimum flow requirements while also ensuring the safe operation of PVP. This would reduce minimum instream flows from the PVP into the East Fork of the Russian River from 45 cfs to 15 cfs. Current minimum instream flow requirements are based on cumulative inflow into Lake Pillsbury, which is not accurately reflecting water supply conditions in the Russian River. The cumulative inflow from October 31, 2020 to December 31, 2020 is above the criteria of 8,000 ac-ft, which changed the water supply condition from a Dry to Normal designation on January 1, 2021. This has increased the minimum instream flows required in the Upper Russian River to a rate that current storage in Lake Mendocino may not be able to reliably sustain if dry weather persists. If storage in Lake Mendocino is depleted, then water to maintain the Upper Russian River flows through to the fall of 2021 will not be available to support the multitude of downstream beneficial uses, which includes habitat for threatened and endangered species, agriculture, and domestic/municipal water supplies. B. Actions by Regulatory Agencies for Protection of Natural Resources and the Environment CEQA Guidelines Sections 15307 and 15308 provide that actions taken by regulatory agencies to assure the maintenance, restoration or enhancement of a natural resource and the environment are categorically exempt. The proposed temporary urgency change to Sonoma Water’s water right Permit 12947A would conserve water in Lake Mendocino to support beneficial uses downstream of Lake Mendocino, including habitat for listed Russian River salmonid fisheries, agricultural and municipal use, and recreation. C. Existing Facilities CEQA Guidelines Section 15301(i) provides, generally, that the operation of existing facilities involving negligible or no expansion of use beyond that existing at the time of the lead agency’s determination is categorically exempt from CEQA. The examples in subdivision (i) of Section 15301(i) specifically provide that the maintenance of streamflows to protect fish and wildlife resources is exempt. Sonoma Water’s request to would not expand Sonoma Water’s use or increase the water diversions available to Sonoma Water for consumptive purposes. The proposed change in would still be within the existing minimum instream flows established by SWRCB Decision 1610.