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HomeMy WebLinkAbout06.17.2024 Board Correspondence - FW_ Project Operations Compliance Report submitted in FERC P-803-000 by Pacific Gas and Electric Company,et al.From:Clerk of the Board To:Bennett, Robin; Clerk of the Board; Connelly, Bill; Cook, Holly; Cook, Robin; Durfee, Peter; Jessee, Meegan; Kimmelshue, Tod; Kitts, Melissa; Lee, Lewis; Pickett, Andy; Ritter, Tami; Stephens, Brad J.; Sweeney, Kathleen; Teeter, Doug; Zepeda, Elizabeth; Loeser, Kamie Cc:Nevers, Dawn Subject:Board Correspondence - FW: Project Operations Compliance Report submitted in FERC P-803-000 by Pacific Gas and Electric Company,et al. Date:Monday, June 17, 2024 1:28:33 PM Please see Board Correspondence - -----Original Message----- From: 'FERC eSubscription' <eSubscription@ferc.gov> Sent: Monday, June 17, 2024 5:36 AM Subject: Project Operations Compliance Report submitted in FERC P-803-000 by Pacific Gas and Electric Company,et al. .ATTENTION: This message originated from outside Butte County. Please exercise judgment before opening attachments, clicking on links, or replying.. On 6/17/2024, the following Filing was submitted to the Federal Energy Regulatory Commission (FERC), Washington D.C.: Filer: Pacific Gas and Electric Company Pacific Gas & Electric Company (as Agent) Docket(s): P-803-000 Lead Applicant: Pacific Gas and Electric Company Filing Type: Project Operations Compliance Report Description: Pacific Gas and Electric Company submits 2024 Operations and Maintenance Plan re the DeSabla-Centerville Hydroelectric Project under P-803. To view the document for this Filing, click here https://urldefense.com/v3/__https://elibrary.ferc.gov/eLibrary/filelist?accession_num=20240617- 5022__;!!KNMwiTCp4spf!AMHDLPBt_k6KnGmxhijlajsDs7qvB3_SYp9iGeBSf2Y7UssjjGQ_API0eODjlcWMvaCqmh14eMziouSMQQwiz42PQpe4fzNBRRit$ To modify your subscriptions, click here: ------------------------------------------------------------------------ Please do not respond to this email. Online help is available here: https://urldefense.com/v3/__http://www.ferc.gov/efiling-help.asp__;!!KNMwiTCp4spf!AMHDLPBt_k6KnGmxhijlajsDs7qvB3_SYp9iGeBSf2Y7UssjjGQ_API0eODjlcWMvaCqmh14eMziouSMQQwiz42PQpe4f4Jw5eNJ$ or for phone support, call 866-208-3676. Power Generation 300 Lakeside Drive Oakland, CA 94612 Mailing Address: P.O. Box 28209 Oakland, CA 94604 June 14, 2024 Via Electronic Submittal (E-File) Debbie-Anne Reese, Acting Secretary Federal Energy Regulatory Commission 888 First Street, NE Washington, D.C. 20426 RE: DeSabla-Centerville Hydroelectric Project, FERC No. 803-CA 2024 Operations and Maintenance Plan Dear Secretary Reese: Pursuant to the Federal Energy Regulatory Commission's (FERC) "Order Amending Temperature Requirements" (Order) issued on August 20, 1998, Pacific Gas and Electric Company (PG&E) is submitting its 2024 Operations and Maintenance Plan (2024 O&M Plan) for the DeSabla – Centerville Hydroelectric Project, FERC No. 803 (Project). Consistent with FERC's Order, PG&E held a meeting to discuss the 2024 O&M Plan on April 25, 2024, with the National Marine Fisheries Service, California Department of Fish and Wildlife, the U.S. Fish and Wildlife Service, and the United States Forest Service. The enclosed 2024 O&M Plan addresses the coordinated operation of the Project and continues to provide for water temperature monitoring and a forecasting approach to detect changing summer weather conditions in a timely manner. The draft 2024 O&M Plan was provided to the Resource Agencies via email on April 24, 2024. Comments and edits to the draft version are provided with this filing as enclosures 2 and 3. Provided as enclosure 1 is the clean final version of the 2024 O&M Plan. Should you have any questions or comments, please do not hesitate to contact PG&E’s senior license coordinator, Megan Young at 530-335-5602. Sincerely, Matthew Joseph Supervisor, Hydro License Management Enclosures: 1. Clean Version of 2024 DeSabla Centerville Operations and Maintenance Plan 2. Draft Redlined version of 2024 DeSabla Centerville Operations and Maintenance Plan 3. Agency Comment Matrix2024 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 Debbie-Anne Reese, Acting Secretary June 14, 2024 Page 2 cc: via email w/enclosures Tracy McReynolds (CDFW) – Tracy.McReynolds@wildlife.ca.gov Grant Henley (CDFW)- Grantton.Henley@wildlife.ca.gov Anna Allison (CDFW) – Anna.allison@wildlife.ca.gov Beth Lawson (CDFW) – Beth.Lawson@wildlife.ca.gov Ellen McBride (NOAA Fisheries) – ellen.mcbride@noaa.gov Allison Bosworth (NOAA Fisheries) Allison.Bosworth@noaa.gov Steve Edmondson (NOAA Fisheries) – steve.edmondson@noaa.gov Tristan Leong (USFS)– tleong@fs.fed.us Stephanie Millsap (USFWS) - Stephanie_Millsap@fws.gov Brittany Reaves (USFWS) - brittany_reaves@fws.gov Eric Bradbury (SWRCB) – Eric.Bradburry@waterboards.ca.gov Document Accession #: 20240617-5022 Filed Date: 06/17/2024 ENCLOSURE 1 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan PACIFIC GAS AND ELECTRIC COMPANY DeSabla-Centerville Hydroelectric Project FERC No. 803 2024 OPERATIONS AND MAINTENANCE PLAN Prepared By: June 2024 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 2 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company TABLE OF CONTENTS 1.0 Introduction ....................................................................................................................... 3 1.1 Project Features ........................................................................................... 3 1.2 Project Benefits to Butte Creek Habitat ...................................................... 4 1.3 Background ................................................................................................. 4 2.0 Water Year Type and Operations ................................................................................. 10 2.1 Water Year Type for 2024 ........................................................................ 10 2.2 Reservoir Operations for 2024................................................................... 10 2.3 Lower Centerville Canal Operations for 2024 ........................................... 13 2.4 2024 Minimum Instream Flow Variance ................................................... 13 2.5 Contingency for Extreme Heat Event During the Holding Period ............. 13 2.6 Spawning Flows in Butte Creek ................................................................. 15 2.7 Scheduled and Emergency Maintenance and Operations .......................... 16 3.0 Water Quality Monitoring.............................................................................................. 18 4.0 Consultation ..................................................................................................................... 20 5.0 References ........................................................................................................................ 21 EXHIBITS Exhibit A Map of Project Area Exhibit B Historical Runoff Forecast and Water Year Type Since 1998 Exhibit C 2024 Scheduled Maintenance and Outages Exhibit D PG&E Seasonal Monitoring Locations 2024 Exhibit E 2024 Plan Comment Matrix 1.0 Introduction Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 3 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 1.0 Introduction The Operations and Maintenance Plan’s (O&M Plan) objective is to manage flows from the DeSabla-Centerville Hydroelectric Project (Project) reservoirs to support holding, spawning, and rearing Central Valley (CV) spring-run Chinook salmon (Oncorhynchus tshawytscha; CVSRCS) use in the reaches of Butte Creek below the DeSabla Powerhouse during 2024. It also documents Pacific Gas and Electric Company’s (PG&E) scheduled outages that allow for the Project maintenance activities. In addition, this O&M Plan outlines the procedures and practices PG&E will strive to follow in the operation of the Project to enhance and protect habitat for CV spring- run Chinook salmon. Finally, this O&M Plan provides the basis for modification of the reservoir temperature release criteria established in the Federal Energy Regulatory Commission (FERC) “Order Approving Water Temperature Study Report” issued August 21, 1997, as amended by FERC’s “Order Amending Temperature Requirements” issued August 20, 1998. 1.1 Project Features The DeSabla – Centerville Hydroelectric Project includes the following features which are depicted on the project map which is included with this O&M Plan as Exhibit A: Reservoirs and Forebays: • Round Valley Reservoir (also known as Snag Lake) • Philbrook Reservoir • DeSabla Forebay Canals and related features: • Butte Canal (out of service for the 2024 season) • Hendricks Canal • Toadtown Canal Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 4 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company • Upper Centerville Canal • Lower Centerville Canal(LCC) • associated diversion dams, feeders, and spillway channels Powerhouses: • Toadtown Powerhouse • DeSabla Powerhouse • Centerville Powerhouses (CVPH) 1.2Project Benefits to Butte Creek Habitat 1. Water diverted from the West Branch Feather River at the Hendricks Diversion Dam (including releases from Philbrook and Round Valley Reservoirs) can increase the total flow available in Butte Creek below DeSabla Powerhouse by up to approximately 40% in July and August (depending on water availability in Butte Creek). 2. Water imported from the West Branch Feather River provides additional water to cool water temperatures in reaches of Butte Creek used by CVSRCSfor over-summering by providing releases from Philbrook Reservoir when storage is available. The increased flow from the Philbrook Reservoir releases help minimize heating by decreasing travel time in the Hendricks Canal and by reducing the residence time in the DeSabla Forebay. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.3 Background The Project storage reservoirs (Round Valley and Philbrook Reservoirs) are in the West Branch Feather River watershed. Project diversions are made from this drainage at the Hendricks Diversion Dam. Due to the larger storage capacity and depth of Philbrook Reservoir (5,000 acre- feet) relative to Round Valley Reservoir (1,200 acre-feet), the water temperature tends to stay cooler for a longer period in Philbrook Reservoir. Accordingly, since 1998 PG&E has released water from Round Valley Reservoir first, to effectively manage the temperature of water released into Butte Creek. In more recent years, increases in flow at Round Valley (above minimum instream flow requirements) have been made later to reserve water in Philbrook Reservoir so that it is available during the hottest time of the holding period. Due to the input of cool water from springs near Coon Hollow and West Branch Feather River basin snow melt, releases from Round Valley Reservoir occurring in the summer (June –August) have not increased water temperatures at Hendricks Diversion Dam. PG&E notifies the Resource Agencies when water releases commence from Round Valley Reservoir. Releases from Round Valley Reservoir begin between early May to mid-July when there is capacity in the Hendricks canal and, depending upon the amount released, continues for a period of approximately one to two months. Philbrook releases are typically delayed until releases from Round Valley begin to diminish or heat storm events occur. Since 2016 water from Round Valley Reservoir has been used to augment flow releases from Philbrook Reservoir. The release valves from these reservoirs must be operated manually and the travel time of the water released from these reservoirs to the Lower Centerville Diversion Dam (LCDD) is approximately 21 to 29 hours. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 6 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Travel time of operator to the valve locations is approximately 1½ hours during workdays and may be up to 4 hours on weekends. On August 21, 1997, the FERC issued an Order placing temperature restrictions (17º C at Round Valley and 18º C at Philbrook) on the releases from these dams. On August 20, 1998, and 2020- 2021, the FERC revised its Order to allow for modification of the criteria upon mutual agreement of the National Marine Fisheries Service (NMFS), the California Department of Fish and Wildlife (CDFW), and the United States Fish and Wildlife Service (USFWS); PG&E has also included the State Water Resource Control Board (SWRCB), and United States Forest Service (USFS) in this consultation process. These five agencies are referred to as the Resource Agencies in this Plan. Since 1999, this agreement has been accomplished by way of an annual O&M Plan. Reservoir operation has been based on expected water year conditions. Pursuant to FERC’s August 21, 1998, Order, this O&M Plan is annually updated and modified as appropriate in consultation with the Resources Agencies. This consultation group, composed of PG&E and the Resource Agencies, is called the Resource Group in the remainder of this Plan. Starting in 2016, a schedule of maintenance outages of the DeSabla-Centerville Canals was included in this O&M Plan. Storage in Philbrook Reservoir is used to supplement flows in Butte Creek during the adult CVRSCS holding period. Monitoring data shows that cooler water released from the bottom of Philbrook Reservoir (i.e., the cold-water pool) increases in temperature while traveling through the system and reaches thermal equilibrium at Hendricks Diversion Dam. The Resource Group has agreed that it is a combination of total flow (decreased travel time, increased mass of water Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 7 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company subject to heating) and cold-water releases that help minimize effects of ambient air temperatures to water temperatures in Butte Creek. Generally, the cool- water pool in Philbrook is depleted in late July to early August and release temperatures increase through August (e.g. maximum daily average release temperature of 20.3 ºC occurred on August 17, 2018); however, monitoring data show that after the beginning of August the thermal regime in the basin is such that releases with higher temperatures actually cool as the water travels to Hendricks Diversion Dam (sun declination is lower, canyon walls shade the stream, and cool evenings predominate). Initially, when management of Philbrook flows began in 1998, outflow from the reservoir was increased in response to forecasted heat events and then returned to pre- heat levels to save water. This resulted in a large amount of residual water storage at the end of the holding period, which was then released in September to make room in the reservoir for upcoming winter storms (Exhibit B). The Resource Group has moved away from short-term responses to heat events to releasing outflow from Philbrook in a stepwise fashion; this approach maximizes the use of storage during the holding period and minimizes the amount of residual storage at the end of the holding period. Although the Resource Group had been moving towards this approach in previous years, 2014 was the first year in which this pattern of management was fully employed (Exhibit B). Since 2014, an increase from minimum instream flow begins when room is available in the Hendricks Canal and increases in a stepwise manner (i.e., by 5 to 10 cfs based on predicted heat events). If no heat event is predicted and flows remain steady in the canal, releases are held steady until the next heat event is forecasted. In this way, releases are increased so maximum flow is reached during the hottest period of the summer (mid-July to early August). Maximum release is held for a short period and is based on the amount of water available for the remainder of the holding period. It is then Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 8 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company decreased in a stepwise fashion with timing and quantity of decrease dependent on a balance between heat events, remaining storage availability and the knowledge that as mid-August approaches we expect decreased average daily temperatures. The Resource Group has concluded that this release pattern is beneficial since it utilizes most of the stored Philbrook water during late June through late July when air and Butte Creek water temperatures are at their highest during the holding period. The “stepwise” release pattern from Philbrook Reservoir (as described above) was used during the 2014 – 2020 &2022 holdingperiods. This stepwise release pattern was modified in 2021 because of limited flows and water availability PG&E uses the meteorological forecast and amount of storage in Round Valley and Philbrook Reservoirs to determine the amount and duration of increased flow. This has been shown to result in a pro-active management of water supply. CDFW provides monitoring data and information about abundance, distribution and health of fish, and temperatures at Quartz Bowl to help inform and /support Resource Group decisions. Collectively, the Resource Group agree to a flow proposal based on the information provided. The CVPH went offline in February 2011; from 2011-2013, the diversion of flow into the canal during the holding period continued at the request of the Resource Group. In 2013, diversions were decreased into the LCC after consultation with the Resource Agencies due to the unusually high numbers of CVSRCSholding above CVPH. The water temperature data showed that the temperature benefit of using the LCC decreased as diverted flows into the LCC decreased. The decrease of flow diverted into the LCC was due to the limited availability of water that resulted Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 9 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company from a dry water year. After the experience of 2013, in 2014 and 2015 the Resource Group made a consensus decision to not operate the LCC during the holding period because of the dry water year type. The Resource Group concluded that, , there would likely be insufficient water available to divert enough flow into the LCC to provide a cold-water benefit to any fish holding downstream of the CVPH. The Resource Group made a mutual decision not to run the LCC during the 2016 holding period of CVSRCS, although it was a normal water year. On February 25, 2016, a conference call occurred between representatives of the Resource Group. PG&E sought Resource Agency guidance on whether to operate the LCC during the 2016 holding period. PG&E described the challenges of restoring the LCC to service after a 2.5-year period (2 summer holding periods) of non-operation, including turbidity risk and the resulting potential for negative public perception. PG&E reminded the Resource Agencies that, as the CVPH is inoperable, the LCC is only used to benefit the CVSRCS. The Resource Agencies requested time before offering guidance to PG&E. On March 8, 2016, another conference call was held. PG&E provided additional information showing that because of the limited capacity of the CVPH’s Bypass/Spillway, the use of the LCC without the CVPH decreases the temperature benefit to fish holding in the downstream reaches. There was concurrence among the Resource Group on the call that PG&E would not be requested to put the LCC into service. The Resource Group agreed that availability of the LCC in future years requires more discussion and may depend on the outcome of the FERC License conditions. In 2017-2022 PG&E did not utilize the LCC to benefit water temperature for fish holding in the downstream reaches of CVPH. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 10 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 2.0 WATER YEAR TYPE AND OPERATIONS 2.1 Water Year Type for 2024 The 2024 Water Year Type is currently forecasted to be “Normal” per the definition of the license. The Department of Water Resources (DWR) forecast as of April 1, 2024, indicates that the Feather River Basin April-July runoff into Oroville is expected to be 101% of average. Exhibit B lists historical runoff forecasts and water year types since 1998. 2.2 Reservoir Operations for 2024 In the late summer, early fall of 2023, PG&E completed a geotechnical investigation on the spillway at Round Valley Reservoir in support of a recommendation from the 2015 FERC Part 12D Dam Safety Inspection. In an effort to mitigate risks associated with the data collected from the 2023 Round Valley Reservoir Geotechnical Investigation, PG&E will be implementing an internal justification for continued operation (JCO) limit of 5 feet from spill crest on Round Valley Reservoir Elevation. This will limit the total acre feet usage to 860 acre-feet. The Round Valley low-level outlet (LLO) was closed on April 3, 2024, and then reopened on April 19, 2024, in accordance with PG&E’s internal JCO as mentioned above. The Philbrook LLO is scheduled to release MIF (3 cfs) until mid-summer. PG&E will keep the resources agencies informed regarding LLO operations at Round Valley. Installation of flashboards begins once the water elevation reaches the radial gate spillway, which is 5ft below the bottom of the flashboards. PG&E operations do not anticipate the flashboards will Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 11 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company be installed until mid-June due to the higher-than-normal reservoir elevation; flashboards are typically completely installed by June. The radial gate at Philbrook was closed on May 3, 2024. Reservoir operation for the holding period is as follow: 1. Releases from Round Valley Reservoir begin when there is capacity in the Hendricks Canal. Capacity is dependent upon water year type. As of April 24, 2024Round Valley Reservoir had reached approximately 951-acre feet . Due to the elevation restriction in place in compliance with the JCO, PG&E will only be able to store and use approximately 860 acre-foot of water from Round Valley Reservoir. Releases will begin in late spring from mid-May to late June, again, due to the input of very cool water from springs near Coon Hollow and West Branch Feather River basin snow melt, releases from Round Valley Reservoir occurring in early summer (June – early July) have been shown not to increase water temperatures at Hendricks Diversion Dam. PG&E will notify the Resource Agencies when water releases commence from Round Valley Reservoir. 2. As Round Valley Reservoir nears its minimum elevation, PG&E will consult with the Resource Agencies to determine when releases from Philbrook Reservoir should be increased to avoid a drop in canal flows when Round Valley Reservoir flow runs out. PG&E will closely monitor the drawdown of Round Valley Reservoir as the minimum elevation is approached. 3. The Resource Group will determine the initial release level from Philbrook Reservoir. Factors considered in establishing the actual rate of release include the date upon which releases commence the objective of reserving relatively cool water for a possible extreme Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 12 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company heat event, the level of natural flows, and the objective of maintaining the highest possible flows through the DeSabla Forebay. 4. The “stepwise” release pattern from Philbrook Reservoir will be used in 2024. The Resource Group will determine the initial outflow from Philbrook Reservoir. The Resource Group holds weekly phone call meetings to determine these stepwise increases in outflow (approximately 5 to 10 cfs each) based on predicted heat events. Weekly phone calls also include discussion of weather forecast, reservoir levels, pre- spawning mortality updates(if conducted by CDFW , water temperatures, as measured at the holding pool “Quartz Bowl” by CDFW, and proposed outflow from Philbrook Reservoir. The Resource Group then determine, via weekly meetings, when Philbrook outflow will be decreased using a stepwise reduction (again utilizing meteorology predictions and storage availability); flows are expected to be returned to the minimum release about mid-September. 5. A flow through the forebay of 60 cfs is targeted to reduce residence time and minimize heating of water as it moves through the forebay. The 60 cfs target flow through the DeSabla Forebay will be reviewed during the summer on the weekly calls described above to determine if this rate should be adjusted based on the available releases from Philbrook Reservoir. 6. Water temperature monitoring by PG&E will continue in 2024 at eight stations (Exhibit D), five of which have been used prior to relicensing (since 1998). Installation of recorders occurs in June or as soon thereafter when safe access to the stream channels is possible. Data will be reported to the resource agencies during the 2025 Annual Operations Meeting. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 13 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 7. DWR gage BW12 (available on CDEC, provided on an hourly basis) will be used as the indicator of water temperatures in the Project waters that are diverted from the West Branch Feather River. 2.3 Lower Centerville Canal Operations for 2024 LCC has been out of service since 2013 and will remain out of service. 2.4 2024 Minimum Instream Flow Variance PG&E will be submitting a minimum instream flow (MIF) variance to FERC which will mirror the 2023 variance which was filed with FERC on February 28, 2023. This variance allows for the instantaneous MIF to be averaged over 48 hours with a target between 15 and 7 cfs at compliance point B-40(Hendricks Head Dam), and 2 cfs at compliance point BW-3 (Philbrook Reservoir). During the 2024 CVSRCSholding period, this variance will allow PG&E greater flexibility to operate around the MIFs while staying compliant during short-lived drops in instream flow readings. In addition, the variance at the Hendricks Head Dam will maximize the delivery of flow released from Philbrook to Butte Creek instead of being used to buffer flow to meet instantaneous MIF. 2.5 Contingency for Extreme Heat Event During the Holding Period In anticipation of a possible high ambient air temperature event, the following actions will be taken: 1. Ambient air temperature conditions are a significant factor in determining actual water temperatures in Butte Creek. Starting on June 1 or at such time as the Resource Group determines, PG&E will prepare a weather forecast for the Project area by noon each Monday Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 14 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company and Thursday. The weather forecast will be based on information from USFS weather stations at Cohasset and Chester. PG&E will provide an email copy of the forecast to the Resource Agencies. If air temperatures more than 105ºF for two or more days during the next seven-day period are forecasted at the Cohasset weather station, with the potential for compression heating at higher elevations as confirmed by data from the Chester location, PG&E will send an email to each Resource Agency representative identified in paragraph 4 below advising them that an extreme heat event is forecasted. If the next forecast confirms that an extreme heat event has started or is imminent within the next two days and is expected to continue for over two days, PG&E will send a second email, phone, or fax to one of the individuals at each Resource Agency identified in paragraph 4 to discuss actions to be taken. If personal contact cannot be made and PG&E still believes action needs to be taken, it will initiate efforts to modify Project operation as discussed in paragraphs 2 – 4 below. If action is taken, PG&E will send a third email or phone the Resource Agencies and explain the actions taken. 2. PG&E will coordinate weekly conference calls with the Resource Agencies during the CV SRC holding period. Increased call frequencies will be conducted as requested and agreed upon by the Resource Group. These conference calls are usually conducted from early June through mid-September (as needed). During these conference calls the Resource Group will discuss the results of pre-spawning mortality surveys (if provided by CDFW or NMFS), meteorological forecasts, water temperatures recorded by CDFW at Quartz Bowl Pool, flows and storage in Philbrook Reservoir. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 15 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 3. The actual amount of water released from Philbrook Reservoir during a confirmed extreme heat event will depend on PG&E’s assessment of existing conditions and recommendations and comments received from the Resource Agencies in response to the emails. The individuals to whom PG&E will send e-mails under this section are: • Tracy McReynolds (CDFW) – Tracy.McReynolds@wildlife.ca.gov, (530) 333-7746 • Grant Henley (CDFW)- Grantton.Henley@wildlife.ca.gov, (916) 272-4152 • Anna Allison (CDFW) – Anna.allison@wildlife.ca.gov, (916) 272-4373 • Beth Lawson (CDFW) – Beth.Lawson@wildlife.ca.gov, (916) 358-2875 • Ellen McBride (NOAA Fisheries) – ellen.mcbride@noaa.gov, (916) 930-3722 • Allison Bosworth (NOAA Fisheries) Allison.Bosworth@noaa.gov, (916) 930-5617 • Steve Edmondson (NOAA Fisheries) – steve.edmondson@noaa.gov, (707) 575-6052 • Tristan Leong (USFS)– tristan.leong@usda.gov, (530) 226-2308 • Eric Bradbury (SWRCB) – Eric.Bradbury@waterboards.ca.gov, (916) 327-9401 • Stephanie Millsap (USFWS) - Stephanie_Millsap@fws.gov, (916) 930-2658 • Brittany Reaves (USFWS) - brittany_reaves@fws.gov, (916) 930-5643 2.6 Spawning Flows in Butte Creek As in previous years, it is best to reduce flow from the West Branch Feather River watershed during the fall so that redds are not at risk of being dewatered if an emergency outage occurs on the Hendricks. In the past, flows from the West Branch Feather River were decreased around mid- September when CVSRCS are expected to begin spawning and mean daily temperature decreases naturally and the use of the canals has less of an effect on keeping water temperatures cool. Decreasing flows mid-September ensures that fish spawn and rear in the natural flows of Butte Creek, reduces the potential for redd dewatering. Additionally, this decreases the risk of decreased flow in the case of an emergency canal outage. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 16 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 2.7 Scheduled and Emergency Maintenance and Operations 1. Maintenance Outage Scheduling – To minimize the disruption of flows in Butte Creek during times that are sensitive to CVSRCSholding in Butte Creek, PG&E usually plans to take scheduled canal outages as early as possible in the year. This submission includes all planned outages for PG&E owned tunnels, conduits, or penstocks under FERC licenses. a. On August 10, 2023, an incident occurred at Butte Canal which removed the canal from service. Butte Canal will remain out of service for 2024. 2. Unplanned Outages (2024-2025) - Winter storms, disruption in canal flows caused by slides or fallen trees, unexpected electric transmission system outages, Public Safety Power Shutoffs (PSPS) and other hazardous conditions can disrupt normal Project operation. PG&E shall use its best efforts to minimize impacts that may result from these conditions, including the actions outlined below: 3. Public Safety Power Shutoff (PSPS) - As part of our Community Wildfire Safety Program, PG&E is implementing additional precautionary measures to help reduce the risk of wildfires. For public safety, it may be necessary for us to turn off electricity as a last resort when extreme fire danger conditions are forecasted. This is called a "Public Safety Power Shutoff." See section below for more information on impacts and response. 4. Unit Separation from Electric Grid - If the electric transmission grid, generating unit, a critical support system experiences a problem, or in the event of a PSPS, the generating units automatically separate from the grid and the flow of water to the units is directed away from the turbine. At the Toadtown and DeSabla powerhouses, this is done by means of a bypass device that directs the flow through an energy dissipator bypass and allows the Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 17 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company water to continue moving at approximately the same flow. PG&E will adjust the automatic bypass opening during the summer to reasonably correspond to the operational flow of the powerhouse. The shift from the generating unit to the bypass facility may result in a minor release of turbidity caused by sediment that may have built- up in the bypass system since its last use. During a unit separation or PSPS event, standby portable generators are deployed to supply power to station batteries that power bypass system controls. During a separation from electric grid, PG&E increases patrol of canals as some remote operation of equipment and some remote monitoring will not be available. In preparation for PSPS events, PG&E staffs’ additional personnel to remediate any issues that arise during the duration of the event. 5. Winter Operation and Canal Emergencies – Much of the Project’s canal system traverses steep forested lands. During times of high rainfall and/or high winds, slides, rock falls, and fallen trees can damage canals or block flows. To minimize the potential for damage in the event of a blockage or failure of a canal or flume, PG&E may reduce canal flows or dewater canals in advance of such weather events. In addition, emergency spill gates are located at several locations that are equipped with devices that can be operated remotely to spill water at various locations along the canals. PG&E has installed sensors that report canal flow levels to the operator at the Rock Creek Switching Center. This location is staffed 24 hours a day, 7 days a week, 365 days a year. If a sensor detects an unexpected change in the flow, an alarm is sent to alert the operator on duty. The operator will then dispatch personnel to the location to determine if immediate action can or should be taken to remove water from the canal by activating an emergency spill gate. The emergency spill gates are placed at Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 18 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company locations where the channel through which the water will travel is generally protected by rocks and boulders. However, turbidity is possible from vegetative or other debris that may have accumulated in the channel since its last use. Spill channels are routinely inspected at the beginning of the winter season and are typically operated once during a winter high flow event to maintain the prescriptive right for the spill channel and keep the release gate clear of material. This operation results in an incremental increase in the turbidity of Butte Creek for a short period of time, which is typically already elevated during high flow events. Operation of the spill channels that may not be well protected and could likely result in turbidity increases, other than the annual winter operation discussed above, will be operated for emergency purposes only. To avoid releasing water into a damaged canal after a storm event, the canal is patrolled on foot prior to restoring flow. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 3.0 Water Quality Monitoring 19 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 3.0 WATER QUALITY MONITORING PG&E will monitor water temperature at eight seasonal stations during 2024. These are in addition to the real-time, permanent CDEC station at BW-12. Temperature monitoring will generally be conducted between June and September. Results will be presented at the Annual Operations and Management Meeting in 2025. Monitoring locations are identified in Exhibit E. Prior to the start-up of a canal or powerhouse after an outage, which may result in the possible release of turbidity to Butte Creek, PG&E will monitor water quality using two existing continuous monitoring turbidity sensors located in Butte Creek; one sensor is located at the LCDD, the other sensor is on a wing wall of the CVPH tailrace. In the event of a canal failure, spill gate operation or other release that results in a potential for turbidity to Butte Creek, PG&E will secure water quality samples to the extent practicable and taking into consideration personnel safety. The monitoring will be conducted using either grab samples collected by PG&E and tested for turbidity or use data from the two continuous monitoring turbidity meters (noted above), set to sample every 15 minutes. Sampling locations will generally be immediately upstream of the dam or point of diversion and approximately 300 feet downstream of the point of release or return to surface waters. If the point of release to surface waters is not reasonably accessible by vehicle, PG&E will sample at the nearest downstream location that can be safely and readily accessed. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 4.0 Consultation 20 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Turbidity data collected during a canal start-up, etc., will be made available to one of the individuals at each of the Resource Agencies identified in Section E, paragraph 4, in a timely fashion. Water temperature data will be provided to Resource Agency representatives upon request. 4.0 CONSULTATION On August 21, 1997, the FERC issued an order placing temperature restrictions on releases from PG&E’s storage reservoirs in the upper West Branch Feather River watershed. On August 20, 1998 the FERC revised its order to allow for modification of the criteria upon mutual agreement of the NMFS, CDFW and USFWS. Since 1999, this agreement has been accomplished by way of an annual operations plan for these reservoirs. The reservoir operation varies based on water year conditions. Pursuant to FERC’s August 21, 1998 order, this Operations Plan is annually updated and modified as appropriate in consultation with the Resource Agencies. The FERC Order requires the licensee to notify FERC within 30 days after reaching agreement on the O&M Plan. PG&E will meet at least annually with the interested Resource Agencies to discuss and review this O&M Plan. In addition, PG&E will continue to provide updates (generally by email) on Project operations and events to at least one representative from each of the individual Resource Agencies identified in Section D, paragraph 4. A summary report will be prepared on annual operations and Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 4.0 Consultation 21 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company monitoring data, which will include water and air temperatures, reservoir and conveyance operations and actions taken to minimize effects on the CV spring-run Chinook salmon. Nothing in this O&M Plan will be construed as modifying any of the terms and conditions of the DeSabla-Centerville license, FERC No. 803, or in any manner limiting the jurisdiction of the FERC. In the event of any conflict between any of the provisions of this O&M Plan and the license, the provisions of the license will control. PG&E will work with the Resource Agencies, and others, as appropriate, to seek ways to promote prudent land management practices by others where such practices may directly or indirectly impact safe, reliable canal operations. Nothing in this O&M Plan will be construed as either PG&E or the Resource Agencies accepting responsibility for conditions or damage that may be the result of the actions, or inactions, of others. PG&E is assessing the extent and cost of the necessary repairs and continues to evaluate the options for Butte Canal, including the economic impact to PG&E customers of restoring the Canal compared to decommissioning this part of the DeSabla-Centerville Project. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit A 22 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 5.0 REFERENCES PG&E. 2007. DeSabla-Centerville Hydroelectric Project. FERC Project No. 803. License Application. Appendix E6.2.2.3-G Calibration and Scenarios Report. 14 pp. PG&E. 2015. Final Project Operations Plan – 2015. Pacific Gas and Electric Company DeSabla- Centerville Project (FERC No. 803). June 18, 2015 PG&E. 2023. DeSabla-Centerville project (FERC No. 803). Final 2023 Operations and Maintenance Plan. Pacific Gas and Electric Company. August 2023 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit A 23 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT A: Map of Project area. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit B 24 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT B HISTORICAL RUNOFF FORECAST AND WATER YEAR TYPE SINCE 1998 Water Year Runoff Forecast Water Year Type 1998 149% Normal 1999 115% Normal 2000 99% Normal 2001 46% Dry 2002 70% Normal 2003 97% Normal 2004 70% Normal 2005 93% Normal 2006 180% Normal 2007 38% Dry 2008 66% Normal 2009 64% Normal 2010 106% Normal 2011 171% Normal 2012 80% Normal 2013 47% Dry 2014 31% Dry 2015 19% Dry 2016 84% Normal 2017 214% Normal 2018 77% Normal 2019 176% Normal 2020 55% Normal 2021 37% Dry 2022 51% Normal 2023 181% Normal 2024* 101% Normal *as of April 2024 Runoff Forecasts are the published May 1 Bulletin 120 forecast of April – July unimpaired runoff into Oroville Reservoir as a percent of the 50-year average computed by the State of California at that time. Water Year Type is “Dry” if the runoff forecast is 50% or less. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit C 25 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT C 2024 SCHEUDULED MAINTENANCE AND OUTAGES DESABLA-CENTERVILLE 2024 MAINTENANCE AND OUTAGE SCHEDULE LOCATION DESCRIPTION OF WORK DEWATERED Start Date End Date TOADTOWN Canal Canal Annual Canal 04/01/24 05/12/24 HENDRICKS CANAL Canal Annual Canal 04/01/24 05/12/24 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan EXHIBIT D PG&E SEASONAL MONITORING LOCATIONS – 2024 1. Philbrook Creek at release * (Temperature and Flow) 2. WBFR at Hendricks Head Dam * (Temperature and Flow) 3. BW-12 Gage Station reported to CDEC* (Temperature and Flow) 4. Total canal inflow to DeSabla Forebay * (Temperature and Flow) 5. Butte Creek above DeSabla Powerhouse 6. DeSabla Powerhouse tailrace * (Temperature and Flow) 7. Butte Creek at LCDD * (Temperature, Turbidity, and Flow) 8. Butte Creek at Centerville Powerhouse (Temperature and Turbidity) Document Accession #: 20240617-5022 Filed Date: 06/17/2024 ENCLOSURE 2 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan PACIFIC GAS AND ELECTRIC COMPANY DeSabla-Centerville Hydroelectric Project FERC No. 803 2024 OPERATIONS AND MAINTENANCE PLAN Prepared By: June 2024 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 2 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company TABLE OF CONTENTS 1.0 Introduction ..................................................................... Error! Bookmark not defined. 1.1 Project Features ......................................... Error! Bookmark not defined. 1.2 Project Benefits to Butte Creek Habitat .... Error! Bookmark not defined. 1.3 Background ............................................... Error! Bookmark not defined. 2.0 Water Year Type and Operations ................................. Error! Bookmark not defined. 2.1 Water Year Type for 2024 ........................ Error! Bookmark not defined. 2.2 Reservoir Operations for 2024................... Error! Bookmark not defined. 2.3 Lower Centerville Canal Operations for 2024Error! Bookmark not defined. 2.4 2024 Minimum Instream Flow Variance ... Error! Bookmark not defined. 2.5 Contingency for Extreme Heat Event During the Holding Period ...... Error! Bookmark not defined. 2.6 Spawning Flows in Butte Creek ................. Error! Bookmark not defined. 2.7 Scheduled and Emergency Maintenance and OperationsError! Bookmark not defined. 3.0 Water Quality Monitoring.............................................. Error! Bookmark not defined. 4.0 Consultation ..................................................................... Error! Bookmark not defined. 5.0 References ........................................................................ Error! Bookmark not defined. EXHIBITS Exhibit A Map of Project Area Exhibit B Historical Runoff Forecast and Water Year Type Since 1998 Exhibit C 2024 Scheduled Maintenance and Outages Exhibit D PG&E Seasonal Monitoring Locations 2024 Exhibit E 2024 Plan Comment Matrix Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 3 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 1.0 Introduction The Operations and Maintenance Plan’s (O&M Plan) objective is to manage flows from the DeSabla-Centerville Hydroelectric Project (Project) reservoirs to support holding, spawning, and rearing Central Valley (CV) spring-run Chinook salmon (Oncorhynchus tshawytscha; CVSRCS) use in the reaches of Butte Creek below the DeSabla Powerhouse during 2024. It also documents Pacific Gas and Electric Company’s (PG&E) scheduled outages that allow for the Project maintenance activities. In addition, this O&M Plan outlines the procedures and practices PG&E will strive to follow in the operation of the Project to enhance and protect habitat for CV spring - run Chinook salmon. Finally, this O&M Plan provides the basis for modification of the reservoir temperature release criteria established in the Federal Energy Regulatory Commission (FERC) “Order Approving Water Temperature Study Report” issued August 21, 1997, as amended by FERC’s “Order Amending Temperature Requirements” issued August 20, 1998. 1.1 Project Features The DeSabla – Centerville Hydroelectric Project includes the following features which are depicted on the project map which is included with this O&M Plan as Exhibit A: Reservoirs and Forebays: • Round Valley Reservoir (also known as Snag Lake) • Philbrook Reservoir • DeSabla Forebay Canals and related features: • Butte Canal (out of service for the 2024 season) • Hendricks Canal • Toadtown Canal Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 4 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company • Upper Centerville Canal • Lower Centerville Canal(LCC) • associated diversion dams, feeders, and spillway channels Powerhouses: • Toadtown Powerhouse • DeSabla Powerhouse • Centerville Powerhouses (CVPH) 1.2Project Benefits to Butte Creek Habitat 1. Water diverted from the West Branch Feather River at the Hendricks Diversion Dam (including releases from Philbrook and Round Valley Reservoirs) can increase the total flow available in Butte Creek below DeSabla Powerhouse by up to approximately 40% in July and August (depending on water availability in Butte Creek). 2. Water imported from the West Branch Feather River provides additional water to cool water temperatures in reaches of Butte Creek used by CVSRCSfor over-summering by providing releases from Philbrook Reservoir when storage is available. The increased flow from the Philbrook Reservoir releases help minimize heating by decreasing travel time in the Hendricks Canal and by reducing the residence time in the DeSabla Forebay. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.3 Background The Project storage reservoirs (Round Valley and Philbrook Reservoirs) are in the West Branch Feather River watershed. Project diversions are made from this drainage at the Hendricks Diversion Dam. Due to the larger storage capacity and depth of Philbrook Reservoir (5,000 acre- feet) relative to Round Valley Reservoir (1,200 acre-feet), the water temperature tends to stay cooler for a longer period in Philbrook Reservoir. Accordingly, since 1998 PG&E has released water from Round Valley Reservoir first, to effectively manage the temperature of water released into Butte Creek. In more recent years, increases in flow at Round Valley (above minimum instream flow requirements) have been made later to reserve water in Philbrook Reservoir so that it is available during the hottest time of the holding period. Due to the input of cool water from springs near Coon Hollow and West Branch Feather River basin snow melt, releases from Round Valley Reservoir occurring in the summer (June –August) have not increased water temperatures at Hendricks Diversion Dam. PG&E notifies the Resource Agencies when water releases commence from Round Valley Reservoir. Releases from Round Valley Reservoir begin between early May to mid-July when there is capacity in the Hendricks canal and, depending upon the amount released, continues for a period of approximately one to two months. Philbrook releases are typically delayed until releases from Round Valley begin to diminish or heat storm events occur. Since 2016 water from Round Valley Reservoir has been used to augment flow releases from Philbrook Reservoir. The release valves from these reservoirs must be operated manually and the travel time of the water released from these reservoirs to the Lower Centerville Diversion Dam (LCDD) is approximately 21 to 29 hours. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 6 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Travel time of operator to the valve locations is approximately 1½ hours during workdays and may be up to 4 hours on weekends. On August 21, 1997, the FERC issued an Order placing temperature restrictions (17º C at Round Valley and 18º C at Philbrook) on the releases from these dams. On August 20, 1998, and 2020- 2021, the FERC revised its Order to allow for modification of the criteria upon mutual agreement of the National Marine Fisheries Service (NMFS), the California Department of Fish and Wildlife (CDFW), and the United States Fish and Wildlife Service (USFWS); PG&E has also included the State Water Resource Control Board (SWRCB), and United States Forest Service (USFS) in this consultation process. These five agencies are referred to as the Resource Agencies in this Plan. Since 1999, this agreement has been accomplished by way of an annual O&M Plan. Reservoir operation has been based on expected water year conditions. Pursuant to FERC’s August 21, 1998, Order, this O&M Plan is annually updated and modified as appropriate in consultation with the Resources Agencies. This consultation group, composed of PG&E and the Resource Agencies, is called the Resource Group in the remainder of this Plan. Starting in 2016, a schedule of maintenance outages of the DeSabla-Centerville Canals was included in this O&M Plan. Storage in Philbrook Reservoir is used to supplement flows in Butte Creek during the adult CVRSCS holding period. Monitoring data shows that cooler water released from the bottom of Philbrook Reservoir (i.e., the cold-water pool) increases in temperature while traveling through the system and reaches thermal equilibrium at Hendricks Diversion Dam. The Resource Group has agreed that it is a combination of total flow (decreased travel time, increased mass of water Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 7 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company subject to heating) and cold-water releases that help minimize effects of ambient air temperatures to water temperatures in Butte Creek. Generally, the cool- water pool in Philbrook is depleted in late July to early August and release temperatures increase through August (e.g. maximum daily average release temperature of 20.3 ºC occurred on August 17, 2018); however, monitoring data show that after the beginning of August the thermal regime in the basin is such that releases with higher temperatures actually cool as the water travels to Hendricks Diversion Dam (sun declination is lower, canyon walls shade the stream, and cool evenings predominate). Initially, when management of Philbrook flows began in 1998, outflow from the reservoir was increased in response to forecasted heat events and then returned to pre- heat levels to save water. This resulted in a large amount of residual water storage at the end of the holding period, which was then released in September to make room in the reservoir for upcoming winter storms (Exhibit B). The Resource Group has moved away from short-term responses to heat events to releasing outflow from Philbrook in a stepwise fashion; this approach maximizes the use of storage during the holding period and minimizes the amount of residual storage at the end of the holding period. Although the Resource Group had been moving towards this approach in previous years, 2014 was the first year in which this pattern of management was fully employed (Exhibit B). Since 2014, an increase from minimum instream flow begins when room is available in the Hendricks Canal and increases in a stepwise manner (i.e., by 5 to 10 cfs based on predicted heat events). If no heat event is predicted and flows remain steady in the canal, releases are held steady until the next heat event is forecasted. In this way, releases are increased so maximum flow is reached during the hottest period of the summer (mid-July to early August). Maximum release is held for a short period and is based on the amount of water available for the remainder of the holding period. It is then Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 8 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company decreased in a stepwise fashion with timing and quantity of decrease dependent on a balance between heat events, remaining storage availability and the knowledge that as mid-August approaches we expect decreased average daily temperatures. The Resource Group has concluded that this release pattern is beneficial since it utilizes most of the stored Philbrook water during late June through late July when air and Butte Creek water temperatures are at their highest during the holding period. The “stepwise” release pattern from Philbrook Reservoir (as described above) was used during the 2014 – 2020 &2022 holdingperiods. This stepwise release pattern was modified in 2021 because of limited flows and water availability PG&E uses the meteorological forecast and amount of storage in Round Valley and Philbrook Reservoirs to determine the amount and duration of increased flow. This has been shown to result in a pro-active management of water supply. CDFW provides monitoring data and information about abundance, distribution and health of fish, and temperatures at Quartz Bowl to help inform and /support Resource Group decisions. Collectively, the Resource Group agree to a flow proposal based on the information provided. The CVPH went offline in February 2011; from 2011-2013, the diversion of flow into the canal during the holding period continued at the request of the Resource Group. In 2013, diversions were decreased into the LCC after consultation with the Resource Agencies due to the unusually high numbers of CVSRCSholding above CVPH. The water temperature data showed that the temperature benefit of using the LCC decreased as diverted flows into the LCC decreased. The decrease of flow diverted into the LCC was due to the limited availability of water that resulted Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 1.0 Introduction 9 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company from a dry water year. After the experience of 2013, in 2014 and 2015 the Resource Group made a consensus decision to not operate the LCC during the holding period because of the dry water year type. The Resource Group concluded that, , there would likely be insufficient water available to divert enough flow into the LCC to provide a cold-water benefit to any fish holding downstream of the CVPH. The Resource Group made a mutual decision not to run the LCC during the 2016 holding period of CVSRCS, although it was a normal water year. On February 25, 2016, a conference call occurred between representatives of the Resource Group. PG&E sought Resource Agency guidance on whether to operate the LCC during the 2016 holding period. PG&E described the challenges of restoring the LCC to service after a 2.5-year period (2 summer holding periods) of non-operation, including turbidity risk and the resulting potential for negative public perception. PG&E reminded the Resource Agencies that, as the CVPH is inoperable, the LCC is only used to benefit the CVSRCS. The Resource Agencies requested time before offering guidance to PG&E. On March 8, 2016, another conference call was held. PG&E provided additional information showing that because of the limited capacity of the CVPH’s Bypass/Spillway, the use of the LCC without the CVPH decreases the temperature benefit to fish holding in the downstream reaches. There was concurrence among the Resource Group on the call that PG&E would not be requested to put the LCC into service. The Resource Group agreed that availability of the LCC in future years requires more discussion and may depend on the outcome of the FERC License conditions. In 2017-2022 PG&E did not utilize the LCC to benefit water temperature for fish holding in the downstream reaches of CVPH. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 10 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 2.0 WATER YEAR TYPE AND OPERATIONS 2.1 Water Year Type for 2024 The 2024 Water Year Type is currently forecasted to be “Normal” per the definition of the license. The Department of Water Resources (DWR) forecast as of April 1, 2024, indicates that the Feather River Basin April-July runoff into Oroville is expected to be 101% of average. Exhibit B lists historical runoff forecasts and water year types since 1998. 2.2 Reservoir Operations for 2024 In the late summer, early fall of 2023, PG&E completed a geotechnical investigation on the spillway at Round Valley Reservoir in support of a recommendation from the 2015 FERC Part 12D Dam Safety Inspection. In an effort to mitigate risks associated with the data collected from the 2023 Round Valley Reservoir Geotechnical Investigation, PG&E will be implementing an internal justification for continued operation (JCO) limit of 5 feet from spill crest on Round Valley Reservoir Elevation. This will limit the total acre feet usage to 860 acre-feet. The Round Valley low-level outlet (LLO) was closed on April 3, 2024, and then reopened on April 19, 2024, in accordance with PG&E’s internal JCO as mentioned above. The Philbrook LLO is scheduled to release MIF (3 cfs) until mid-summer. PG&E will keep the resources agencies informed regarding LLO operations at Round Valley. Installation of flashboards begins once the water elevation reaches the radial gate spillway, which is 5ft below the bottom of the flashboards. PG&E operations do not anticipate the flashboards will Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 11 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company be installed until mid-June due to the higher-than-normal reservoir elevation; flashboards are typically completely installed by June. The radial gate at Philbrook was closed on May 3, 2024. Reservoir operation for the holding period is as follow: 1. Releases from Round Valley Reservoir begin when there is capacity in the Hendricks Canal. Capacity is dependent upon water year type. As of April 24, 2024Round Valley Reservoir had reached approximately 951-acre feet . Due to the elevation restriction in place in compliance with the JCO, PG&E will only be able to store and use approximately 860 acre-foot of water from Round Valley Reservoir. Releases will begin in late spring from mid-May to late June, again, due to the input of very cool water from springs near Coon Hollow and West Branch Feather River basin snow melt, releases from Round Valley Reservoir occurring in early summer (June – early July) have been shown not to increase water temperatures at Hendricks Diversion Dam. PG&E will notify the Resource Agencies when water releases commence from Round Valley Reservoir. 2. As Round Valley Reservoir nears its minimum elevation, PG&E will consult with the Resource Agencies to determine when releases from Philbrook Reservoir should be increased to avoid a drop in canal flows when Round Valley Reservoir flow runs out. PG&E will closely monitor the drawdown of Round Valley Reservoir as the minimum elevation is approached. 3. The Resource Group will determine the initial release level from Philbrook Reservoir. Factors considered in establishing the actual rate of release include the date upon which releases commence the objective of reserving relatively cool water for a possibl e extreme Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 12 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company heat event, the level of natural flows, and the objective of maintaining the highest possible flows through the DeSabla Forebay. 4. The “stepwise” release pattern from Philbrook Reservoir will be used in 2024. The Resource Group will determine the initial outflow from Philbrook Reservoir. The Resource Group holds weekly phone call meetings to determine these stepwise increases in outflow (approximately 5 to 10 cfs each) based on predicted heat events. Weekly phone calls also include discussion of weather forecast, reservoir levels, pre- spawning mortality updates(if conducted by CDFW , water temperatures, as measured at the holding pool “Quartz Bowl” by CDFW, and proposed outflow from Philbrook Reservoir. The Resource Group then determine, via weekly meetings, when Philbrook outflow will be decreased using a stepwise reduction (again utilizing meteorology predictions and storage availability); flows are expected to be returned to the minimum release about mid-September. 5. A flow through the forebay of 60 cfs is targeted to reduce residence time and minimize heating of water as it moves through the forebay. The 60 cfs target flow through the DeSabla Forebay will be reviewed during the summer on the weekly calls described above to determine if this rate should be adjusted based on the available releases from Philbrook Reservoir. 6. Water temperature monitoring by PG&E will continue in 2024 at eight stations (Exhibit D), five of which have been used prior to relicensing (since 1998). Installation of recorders occurs in June or as soon thereafter when safe access to the stream channels is possible. Data will be reported to the resource agencies during the 2025 Annual Operations Meeting. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 13 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 7. DWR gage BW12 (available on CDEC, provided on an hourly basis) will be used as the indicator of water temperatures in the Project waters that are diverted from the West Branch Feather River. 2.3 Lower Centerville Canal Operations for 2024 LCC has been out of service since 2013 and will remain out of service. 2.4 2024 Minimum Instream Flow Variance PG&E will be submitting a minimum instream flow (MIF) variance to FERC which will mirror the 2023 variance which was filed with FERC on February 28, 2023. This variance allows for the instantaneous MIF to be averaged over 48 hours with a target between 15 and 7 cfs at compliance point B-40(Hendricks Head Dam), and 2 cfs at compliance point BW-3 (Philbrook Reservoir). During the 2024 CVSRCSholding period, this variance will allow PG&E greater flexibility to operate around the MIFs while staying compliant during short-lived drops in instream flow readings. In addition, the variance at the Hendricks Head Dam will maximize the delivery of flow released from Philbrook to Butte Creek instead of being used to buffer flow to meet instantaneous MIF. 2.5 Contingency for Extreme Heat Event During the Holding Period In anticipation of a possible high ambient air temperature event, the following actions will be taken: 1. Ambient air temperature conditions are a significant factor in determining actual water temperatures in Butte Creek. Starting on June 1 or at such time as the Resource Group determines, PG&E will prepare a weather forecast for the Project area by noon each Monday Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 14 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company and Thursday. The weather forecast will be based on information from USFS weather stations at Cohasset and Chester. PG&E will provide an email copy of the forecast to the Resource Agencies. If air temperatures more than 105ºF for two or more days during the next seven-day period are forecasted at the Cohasset weather station, with the potential for compression heating at higher elevations as confirmed by data from the Chester location, PG&E will send an email to each Resource Agency representative identified in paragraph 4 below advising them that an extreme heat event is forecasted. If the next forecast confirms that an extreme heat event has started or is imminent within the next two days and is expected to continue for over two days, PG&E will send a second email, phone, or fax to one of the individuals at each Resource Agency identified in paragraph 4 to discuss actions to be taken. If personal contact cannot be made and PG&E still believes action needs to be taken, it will initiate efforts to modify Project operation as discussed in paragraphs 2 – 4 below. If action is taken, PG&E will send a third email or phone the Resource Agencies and explain the actions taken. 2. PG&E will coordinate weekly conference calls with the Resource Agencies during the CV SRC holding period. Increased call frequencies will be conducted as requested and agreed upon by the Resource Group. These conference calls are usually conducted from early June through mid-September (as needed). During these conference calls the Resource Group will discuss the results of pre-spawning mortality surveys (if provided by CDFW or NMFS), meteorological forecasts, water temperatures recorded by CDFW at Quartz Bowl Pool, flows and storage in Philbrook Reservoir. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 15 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 3. The actual amount of water released from Philbrook Reservoir during a confirmed extreme heat event will depend on PG&E’s assessment of existing conditions and recommendations and comments received from the Resource Agencies in response to the emails. The individuals to whom PG&E will send e-mails under this section are: • Tracy McReynolds (CDFW) – Tracy.McReynolds@wildlife.ca.gov, (530) 333-7746 • Grant Henley (CDFW)- Grantton.Henley@wildlife.ca.gov, (916) 272-4152 • Anna Allison (CDFW) – Anna.allison@wildlife.ca.gov, (916) 272-4373 • Beth Lawson (CDFW) – Beth.Lawson@wildlife.ca.gov, (916) 358-2875 • Ellen McBride (NOAA Fisheries) – ellen.mcbride@noaa.gov, (916) 930-3722 • Allison Bosworth (NOAA Fisheries) Allison.Bosworth@noaa.gov, (916) 930-5617 • Steve Edmondson (NOAA Fisheries) – steve.edmondson@noaa.gov, (707) 575-6052 • Tristan Leong (USFS)– tristan.leong@usda.gov, (530) 226-2308 • Eric Bradbury (SWRCB) – Eric.Bradbury@waterboards.ca.gov, (916) 327-9401 • Stephanie Millsap (USFWS) - Stephanie_Millsap@fws.gov, (916) 930-2658 • Brittany Reaves (USFWS) - brittany_reaves@fws.gov, (916) 930-5643 2.6 Spawning Flows in Butte Creek As in previous years, it is best to reduce flow from the West Branch Feather River watershed during the fall so that redds are not at risk of being dewatered if an emergency outage occurs on the Hendricks. In the past, flows from the West Branch Feather River were decreased around mid- September when CVSRCS are expected to begin spawning and mean daily temperature decreases naturally and the use of the canals has less of an effect on keeping water temperatures cool. Decreasing flows mid-September ensures that fish spawn and rear in the natural flows of Butte Creek, reduces the potential for redd dewatering. Additionally, this decreases the risk of decreased flow in the case of an emergency canal outage. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 16 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 2.7Scheduled and Emergency Maintenance and Operations 1. Maintenance Outage Scheduling – To minimize the disruption of flows in Butte Creek during times that are sensitive to CVSRCSholding in Butte Creek, PG&E usually plans to take scheduled canal outages as early as possible in the year. This submission includes all planned outages for PG&E owned tunnels, conduits, or penstocks under FERC licenses. a. On August 10, 2023, an incident occurred at Butte Canal which removed the canal from service. Butte Canal will remain out of service for 2024. 2. Unplanned Outages (2024-2025) - Winter storms, disruption in canal flows caused by slides or fallen trees, unexpected electric transmission system outages, Public Safety Power Shutoffs (PSPS) and other hazardous conditions can disrupt normal Project operation. PG&E shall use its best efforts to minimize impacts that may result from these conditions, including the actions outlined below: 3. Public Safety Power Shutoff (PSPS) - As part of our Community Wildfire Safety Program, PG&E is implementing additional precautionary measures to help reduce the risk of wildfires. For public safety, it may be necessary for us to turn off electricity as a last resort when extreme fire danger conditions are forecasted. This is called a "Public Safety Power Shutoff." See section below for more information on impacts and response. 4. Unit Separation from Electric Grid - If the electric transmission grid, generating unit, a critical support system experiences a problem, or in the event of a PSPS, the generating units automatically separate from the grid and the flow of water to the units is directed away from the turbine. At the Toadtown and DeSabla powerhouses, this is done by means of a bypass device that directs the flow through an energy dissipator bypass and allows the Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 17 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company water to continue moving at approximately the same flow. PG&E will adjust the automatic bypass opening during the summer to reasonably correspond to the operational flow of the powerhouse. The shift from the generating unit to the bypass facility may result in a minor release of turbidity caused by sediment that may have built- up in the bypass system since its last use. During a unit separation or PSPS event, standby portable generators are deployed to supply power to station batteries that power bypass system controls. During a separation from electric grid, PG&E increases patrol of canals as some remote operation of equipment and some remote monitoring will not be available. In preparation for PSPS events, PG&E staffs’ additional personnel to remediate any issues that arise during the duration of the event. 5. Winter Operation and Canal Emergencies – Much of the Project’s canal system traverses steep forested lands. During times of high rainfall and/or high winds, slides, rock falls, and fallen trees can damage canals or block flows. To minimize the potential for damage in the event of a blockage or failure of a canal or flume, PG&E may reduce canal flows or dewater canals in advance of such weather events. In addition, emergency spill gates are located at several locations that are equipped with devices that can be operated remotely to spill water at various locations along the canals. PG&E has installed sensors that report canal flow levels to the operator at the Rock Creek Switching Center. This location is staffed 24 hours a day, 7 days a week, 365 days a year. If a sensor detects an unexpected change in the flow, an alarm is sent to alert the operator on duty. The operator will then dispatch personnel to the location to determine if immediate action can or should be taken to remove water from the canal by activating an emergency spill gate. The emergency spill gates are placed at Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 2.0 Water Year Type and Operations 18 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company locations where the channel through which the water will travel is generally protected by rocks and boulders. However, turbidity is possible from vegetative or other debris that may have accumulated in the channel since its last use. Spill channels are routinely inspected at the beginning of the winter season and are typically operated once during a winter high flow event to maintain the prescriptive right for the spill channel and keep the release gate clear of material. This operation results in an incremental increase in the turbidity of Butte Creek for a short period of time, which is typically already elevated during high flow events. Operation of the spill channels that may not be well protected and could likely result in turbidity increases, other than the annual winter operation discussed above, will be operated for emergency purposes only. To avoid releasing water into a damaged canal after a storm event, the canal is patrolled on foot prior to restoring flow. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 3.0 Water Quality Monitoring 19 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 3.0 WATER QUALITY MONITORING PG&E will monitor water temperature at eight seasonal stations during 2024. These are in addition to the real-time, permanent CDEC station at BW-12. Temperature monitoring will generally be conducted between June and September. Results will be presented at the Annual Operations and Management Meeting in 2025. Monitoring locations are identified in Exhibit E. Prior to the start-up of a canal or powerhouse after an outage, which may result in the possible release of turbidity to Butte Creek, PG&E will monitor water quality using two existing continuous monitoring turbidity sensors located in Butte Creek; one sensor is located at the LCDD, the other sensor is on a wing wall of the CVPH tailrace. In the event of a canal failure, spill gate operation or other release that results in a potential for turbidity to Butte Creek, PG&E will secure water quality samples to the extent practicable and taking into consideration personnel safety. The monitoring will be conducted using either grab samples collected by PG&E and tested for turbidity or use data from the two continuous monitoring turbidity meters (noted above), set to sample every 15 minutes. Sampling locations will generally be immediately upstream of the dam or point of diversion and approximately 300 feet downstream of the point of release or return to surface waters. If the point of release to surface waters is not reasonably accessible by vehicle, PG&E will sample at the nearest downstream location that can be safely and readily accessed. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 4.0 Consultation 20 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Turbidity data collected during a canal start-up, etc., will be made available to one of the individuals at each of the Resource Agencies identified in Section E, paragraph 4, in a timely fashion. Water temperature data will be provided to Resource Agency representatives upon request. 4.0 CONSULTATION On August 21, 1997, the FERC issued an order placing temperature restrictions on releases from PG&E’s storage reservoirs in the upper West Branch Feather River watershed. On August 20, 1998 the FERC revised its order to allow for modification of the criteria upon mutual agreement of the NMFS, CDFW and USFWS. Since 1999, this agreement has been accomplished by way of an annual operations plan for these reservoirs. The reservoir operation varies based on water year conditions. Pursuant to FERC’s August 21, 1998 order, this Operations Plan is annually updated and modified as appropriate in consultation with the Resource Agencies. The FERC Order requires the licensee to notify FERC within 30 days after reaching agreement on the O&M Plan. PG&E will meet at least annually with the interested Resource Agencies to discuss and review this O&M Plan. In addition, PG&E will continue to provide updates (generally by email) on Project operations and events to at least one representative from each of the individual Resource Agencies identified in Section D, paragraph 4. A summary report will be prepared on annual operations and Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan 4.0 Consultation 21 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company monitoring data, which will include water and air temperatures, reservoir and conveyance operations and actions taken to minimize effects on the CV spring-run Chinook salmon. Nothing in this O&M Plan will be construed as modifying any of the terms and conditions of the DeSabla-Centerville license, FERC No. 803, or in any manner limiting the jurisdiction of the FERC. In the event of any conflict between any of the provisions of this O&M Plan and the license, the provisions of the license will control. PG&E will work with the Resource Agencies, and others, as appropriate, to seek ways to promote prudent land management practices by others where such practices may directly or indirectly impact safe, reliable canal operations. Nothing in this O&M Plan will be construed as either PG&E or the Resource Agencies accepting responsibility for conditions or damage that may be the result of the actions, or inactions, of others. PG&E is assessing the extent and cost of the necessary repairs and continues to evaluate the options for Butte Canal, including the economic impact to PG&E customers of restoring the Canal compared to decommissioning this part of the DeSabla-Centerville Project. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit A 22 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company 5.0 REFERENCESPG&E. 2007. DeSabla-Centerville Hydroelectric Project. FERC Project No. 803. License Application. Appendix E6.2.2.3-G Calibration and Scenarios Report. 14 pp. PG&E. 2015. Final Project Operations Plan – 2015. Pacific Gas and Electric Company DeSabla- Centerville Project (FERC No. 803). June 18, 2015 PG&E. 2023. DeSabla-Centerville project (FERC No. 803). Final 2023 Operations and Maintenance Plan. Pacific Gas and Electric Company. August 2023 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit A 23 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT A: Map of Project area. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit B 24 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT B HISTORICAL RUNOFF FORECAST AND WATER YEAR TYPE SINCE 1998 Water Year Runoff Forecast Water Year Type 1998 149% Normal 1999 115% Normal 2000 99% Normal 2001 46% Dry 2002 70% Normal 2003 97% Normal 2004 70% Normal 2005 93% Normal 2006 180% Normal 2007 38% Dry 2008 66% Normal 2009 64% Normal 2010 106% Normal 2011 171% Normal 2012 80% Normal 2013 47% Dry 2014 31% Dry 2015 19% Dry 2016 84% Normal 2017 214% Normal 2018 77% Normal 2019 176% Normal 2020 55% Normal 2021 37% Dry 2022 51% Normal 2023 181% Normal 2024* 101% Normal *as of April 2024 Runoff Forecasts are the published May 1 Bulletin 120 forecast of April – July unimpaired runoff into Oroville Reservoir as a percent of the 50-year average computed by the State of California at that time. Water Year Type is “Dry” if the runoff forecast is 50% or less. Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit C 25 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT C 2024 SCHEUDULED MAINTENANCE AND OUTAGES DESABLA-CENTERVILLE 2024 MAINTENANCE AND OUTAGE SCHEDULE LOCATION DESCRIPTION OF WORK DURING OUTAGE DEWATERED STRUCTURE Start Date End Date TOADTOWN Canal Canal Annual Canal 04/01/24 05/12/24 HENDRICKS CANAL Canal Annual Canal 04/01/24 05/12/24 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit D 26 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company EXHIBIT D PG&E SEASONAL MONITORING LOCATIONS – 2024 1. Philbrook Creek at release * (Temperature and Flow) 2. WBFR at Hendricks Head Dam * (Temperature and Flow) 3. BW-12 Gage Station reported to CDEC* (Temperature and Flow) 4. Total canal inflow to DeSabla Forebay * (Temperature and Flow) 5. Butte Creek above DeSabla Powerhouse 6. DeSabla Powerhouse tailrace * (Temperature and Flow) 7. Butte Creek at LCDD * (Temperature, Turbidity, and Flow) 8. Butte Creek at Centerville Powerhouse (Temperature and Turbidity) Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit D 27 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit D 28 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit D 29 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Document Accession #: 20240617-5022 Filed Date: 06/17/2024 DeSabla-Centerville Project (FERC Project No. 803) 2024 Operations and Maintenance Plan Exhibit D 30 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Document Accession #: 20240617-5022 Filed Date: 06/17/2024 Exhibit D 31 June 2024 Hydroelectric Project License Compliance ©2024, Pacific Gas and Electric Company Document Accession #: 20240617-5022 Filed Date: 06/17/2024 ENCLOSURE 3 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 Exhibit E Agency Comment PG&E Resposne USFWS USFWS Comment noted, revisions made. USFWS Round Valley JCO. USFWS capacity restriction at Round Valley Reservoir of 830 acre-feet mentioned by PG&E to the Resource Group at the April 3 and April CDFW than a footnote since this restriction will reduce the amount of water available for maintaining water temperatures in the holding under "Reservoir Opertions for 2024" section CDFW were based on damage to the canal making it unusable and not necessarily related to its inability to benefit the holding salmon population through temperature management. This sentence should be revised to more accurately characterize this information. capacity did not provide the benefit that was seen agreed to discontinue LCC limited operations. 2024 DeSabla- Centerville O&M Plan Comment Matrix Exhibit E June 2024 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 Exhibit E Reservoir of 830 acre-feet mentioned by PG&E to the Resource CDFW Comment noted, revisions made. CDFW Release, the normal water year MIF is 2.0 cfs. MIF of 15 and 7 cfs, are the MIF at Hendricks for a normal and dry year. Please revise Comment noted, revisions made. CDFW Comment noted, revisions made. CDFW Please revise this sentence to include discussion topics of managing reservoir storage, reservoirs releases, and water temperatures in addition to forecast and pre-spawn mortality surveys. The main purpose of these meetings is to discuss water management, so this Comment noted, revisions made. CDFW Comment noted, revisions made. CDFW locations within the holding, spawning and rearing reaches for CV spring-run Chinook salmon if a project facility failure results in a monitoring stations are adequate to characterize any turbidity discharge within the salmon holding and CDFW assessments. The Butte Creek CVSRCS population is in decline in recent years and decommissioning the Butte Canal could potentially negatively impact the long term viability of the population Comment noted. Exhibit E June 2024 Document Accession #: 20240617-5022 Filed Date: 06/17/2024 Document Content(s) PGE20240614_803_DeSablaC_2024_OMPlan.pdf..................................1 Document Accession #: 20240617-5022 Filed Date: 06/17/2024