LONG TERM OUTAGE SUMMARY

Requested by B. Hevlin

2/6/2015

OFFICIAL COORDINATION REQUEST FOR NON-ROUTINE OPERATIONS AND MAINTENANCE

COORDINATION TITLE - 14 DWR 001 Unit 3 RehabilitationCOORDINATION DATE - 18 Dec 2014 Updated Jan 8, 2015PROJECT - Dworshak DamRESPONSE DATE -

Description of the problemDworshak powerhouse generating unit 3 requires a winding and stator core replacement due to a more accurate condition assessment indicating this need and the recent failure of a bar that shut the unit down for over a month while repairs were made. This work will involve a contract to design, manufacture, and install new windings, core and frame, and rehabilitate all rotor poles. This will require the unit to be disassembled for a period of up to 8 months. The unit will also have the bearings inspected for damage, and if needed, replaced with the existing spares. The surface air coolers will also be replaced along with the fiberglass air shrouds for the stator end turns. It was discovered in an earlier inspection of the rotor that weld cracking is present and this will be addressed during this contract. There will be model validation once the unit is returned to service.

Type of outage requiredUnit 3 will be out of service from 1 Sept 2016 to 01 May 2017.Normal temperature augmentation flow begins the first week of July and extends to the third week of September with a discharge of 7-14 kcfs of cold water to cool the Clearwater and Lower Snake Rivers. The discharge rate depends on river temperature. The requirement to maintain 68 degrees in the tailrace at Lower Granite Dam is to provide cooling flow for migrating fish.

Impact on facility operationUnit 3 outage may impact refill/flood control curve operations that require us to make changes to outflow during the construction period. Any additional outflow requirements beyond what Unit 1 and Unit 2 can pass will need to be spilled. This will require additional use of the ROs, which require operator attention to maintain constant flow rates. Flow and temperature augmentation operations will be limited to powerhouse flows from units 1&2 ~5kcfs, and generally RO’s with a maximum flow of 5 kcfs depending on total dissolved gas limitations. Flood control operations will have the same limitations except the full use of the RO’s (approximately 37 kcfs) and the spillway (only available while the pool is above elevation 1555 feet). During the summer augmentation period the spill limitations would revert back to TDG limits (110% without a waiver).

The outage will eliminate DWR’s ability to run a generator as a synchronous condenser, as Unit 1 and Unit 2 cannot function in this capacity due to wicket gate seal leakage. BPA uses Dworshak to provide VAR support on the line during the outage period.

Unit 3 rehab will take up all available space in our erection bay, meaning we will not be able to execute repairs on another unit should a problem arise.

Dates of impacts/repairs1 September 2016 start date is needed to start the unwatering process and conduct alignment measurements so the contractor is ready to begin unit 3 disassembly by 15 September in order to complete all work before flood season in spring, and to meet tribal water rights agreements for cooling of the Snake River for fish migration in July. It is a schedule risk mitigation measure to ensure there is sufficient float in the schedule should the bearings require replacement, or special key parts are damaged beyond repair and require custom fabrication. These items would add 45 work days to the critical path as they cannot be worked concurrent with the winding installation. These items would cause the project to finish too late for flood control, and could impact the discharge requirement starting in July.

Length of time for repairs

The rehabilitation efforts for the frame, core and windings are all critical path activities that take the longest to complete due to the installation methods being all by hand. Since the frame and core are being replaced, this requires re-centering the unit. This process adds two weeks to a normal winding replacement project. The existing winding, core and frame removal will take 30 work days to complete before any new construction can start. The installation of the new frame requires 3 weeks to ensure it is properly positioned and mounted. The stator core is made up of thousands of individual laminations that take 90 work days to stack. The installation of the winding bars takes 30 work days. We expect the contractor will have to conduct two shifts to complete all the work and commission the unit within the 8 month window. The Government then conducts its own commissioning that extends the work another 2 – 3 weeks after the contractor has completed all his work. Once this is complete, it is imperative that the unit run for 3 days while measurements/temperatures are recorded to see if any issues are developing that would require the unit to be taken out of service again for repairs.

Expected impacts on fish passage

The early start up 1 Sept 2016 and work period to 1 May 2017 is designed to minimize the outage effects on flood control and fish passage. If any delays to the commissioning period happen, the buffer period before July 1 will be used for final adjustments.

The Nez Perce flow augmentation period would start out lower and last longer than historically coordinated but very similar to the augmentation in 2014. A table below displays a coordinated operation during this period in 2014. As a result of less capacity at Dworshak, if temperatures during the first two weeks of September are higher than normal, there could be impacts at Lower Granite dam that delay fish from migrating upstream. The reduction of up to 3 kcfs in flow augmentation may affect fish passage in the Lower Snake River, and decrease cold water in the pool at Lower Granite.

The construction and installation of the cold water chimney in the pool at Lower Granite Dam during winter January to March 2016 should have a positive effect on the water temperature of the adult fish ladder and adult trap operation throughout the year. If construction activities are delayed after flow augmentation or possibly extended into the start of flow augmentation in July by the above described construction activities, the normal 10 kcfs supplemental water will not be available until the unit is commissioned.

Comments from agencies/ FPOM meeting notes.

FPOM December 18, 2014:Unit 3 rehab. Moody and Spillane discussed the MOC. Moody explained that Unit 3 has not been rehabbed in a number of years. The schedule is designed to maximize the 8 month work period. Work begins on 8 September 2016 and will continue into May 2017. The goal is to have the unit back in time for summer flow augmentation. Moody explained that the eight months is an ideal schedule with just normal rehab work. If there are issues, it could be extended another 45 days, which brings the unit back just before flow augmentation begins. Some work may be completed between now and 8 September 2016. Fredricks expressed concerns about in-river TDG. He said there isn’t a waiver for the state of Idaho. Bettin said this is just an FYI at this point because there are many issues and river shaping concerns to work through. Spillane said the current schedule is already compressed. Spillane noted that runner repair may occur in 2019. Morrill asked about starting in August if the chimney will provide cooler water. Spillane said the contractor will not be able to make the August date due to the lead time needed for parts. Moody would like this MOC finalized in January 2015. Baus would like time to get comments from partners who request specific operations during the outage schedule. Baus believes the coordination would occur in FPOM and then TMT would be notified of the recommendation. Bettin asked if any work on units 1 and 2 has been identified. Moody would like to not do any work on them. Bettin clarified that we want to make sure the other two units are available while Unit 3 is out of service. Kiefer said IDFG is supportive of the work but he would like to see impacts to summer and spring flood control and augmentation included in the MOC. There are still some issues to address in the MOC. ACTION: NWW will work further on the MOC and bring it back to the January FPOM.

From: Deardorff, Larry A NWW Sent: Wednesday, January 07, 2015 10:45 AMTo: Moody, Gregory P NWWCc: Parker, Greg A NWW; Weston, Dwayne M NWW; Stewart, Lucian P NWW; Setter, Ann L NWWSubject: RE: Dworshak unit 3 (UNCLASSIFIED)

Hi Greg;

2016 will have unit 3 scheduled for cavitation repair which we will address during the rewind, time/availability permitting. Units 1&2 will stay on schedule for normal annual 2 week outages without un-watering. These will be completed by mid December 2016.

Thanks!

Larry Deardorff

O&M Manager

Dworshak Project, USACE

January 8, 2015 FPOM meeting:

14DWR01 Unit 3 Rehab – Spring operation, summer operation discussion by NWW Water Management. Steve Hall explained the proposed project. Work would begin in September 2016 and wrap up in spring/summer 2017. A normal overhaul would require a full calendar year. It was recognized that a 12 month outage would not be acceptable so the compressed schedule has been proposed. Hall went through the balancing of power generation and TDG concerns as well as flood control concerns. Lorz asked if the contract would be written to have flexibility in starting, depending on the type of water year. Lorz also suggested requesting a waiver for the TDG limits. Moody said the start date may be a hard 1 September start date due to the lead time on parts. Conder said starting later may also be needed depending on the water temperatures. Hall said there may be opportunities to start earlier. DWR will do as much as they can to compress the schedule and minimize risk of going longer. FPOM will need to provide concurrence by 22 January. FPOM would like to see language in the contract that allows for scheduling flexibility (15 August – 15 September being the time in question) and dewatering plans for warm water conditions. A TDG waiver should be acquired ahead of time. ACTION: NWW will update the MOC and re-distribute to FPOM for comments. All comments must be back to NWW by 22 January. Setter commented that NWW is putting de-gassers in place. She has asked for documentation from the hatchery to find out if there were any detrimental impacts to juveniles. The LWG temperature mods should be complete during winter 2015-16. ACTION: Lorz said FPAC will discuss the TDG issues and work on the hatchery concerns. Baus said a waiver was written last year so we can use that same template. Setter said Unit 1 will be back in service and will be back to Kaplan operation. In summary, there needs to be flexibility in the contract and there are many contingencies that need to be considered and set in motion.

-----Original Message-----From: Spillane, Kathy M NWW Sent: Monday, January 12, 2015 9:43 AMTo: Moody, Gregory P NWW; Deardorff, Larry A NWW; Hall, Stephen C NWWCc: Setter, Ann L NWWSubject: RE: 14 DWR 001 Unit 3 Rehabilitation.docx (UNCLASSIFIED)

Classification: UNCLASSIFIEDCaveats: NONE

Starting in August would be very difficult. The contractor will already be accelerating the manufacturing of the bars and laminations due to our late award date. I'm happy to see this option, but I will put 01 Sept in the contract. We can try to swing either way by 2 weeks when we have better information early 2016.KathyProject Manager

Comparison of DWR spill to 110% vs. 115% vs. 120% TDG, and resulting reservoir elevation and LWG temperature. Projections calculated 8/19/14 based on current forecasts and models, and are subject to change as conditions develop.

1. Maintain current spill to 110% TDG standard (Units 1&2 + spill to 110% = ~7 kcfs outflow):

a. Achieve 1535’ on ~September 9 (or earlier if Unit 3 returns to service);

b. Achieve 1520’ by September 23 per Dworshak Board Operational Plan;

c. LWG tailrace temps remain below 68°F;

2. Per SOR, spill to 115% TDG (Units 1&2 + spill to 115% = ~8.5 kcfs outflow):

a. If started Thurs 8/22 = Achieve 1535’ on ~September 5 (or earlier if Unit 3 returns to service);

b. Achieve 1520’ by September 23 per Dworshak Board Operational Plan;

c. LWG tailrace temps remain below 68°F;

d. Estimated reduction of LWG ladder/trap temps: -2°F at 20 meters; not much impact at shallower depths.

OFFICIAL COORDINATION REQUEST FOR NON-ROUTINE OPERATIONS AND MAINTENANCE

COORDINATION TITLE- 14 LWG 13 LWG Fish Ladder Temperature Improvements

COORDINATION DATE- 11 SEP 2014

PROJECT- Lower Granite Lock and Dam

RESPONSE DATE- 15 SEP 2014

Description of the problem: The 60% Design for the Lower Granite Fish Ladder Temperature Improvements proposed a schedule for on-site construction in-water between 24 April and 29 May 2014. On-site construction involves 30 hours of dive time to install fiberglass pipes extending the auxiliary pump intakes from 30 feet to about 68 feet deep and 35 hours of dive time to install the thin metal and painted “chimney” box that extends the Diffuser 14 intake from 15 feet to 68 feet deep. Typically a working dive day is 10 hours average (8-12 hours) requiring about 4-8 crew of divers that each are limited to less than one-half hour dive for each descend at 60 feet of depth and less than about a cumulative of 4 or so such dives during a 10 hour period. For the physical safety of working divers from entrainment, construction action dives require closure of hydraulic passage route gates and valve closure within 100 feet of the diver locations in the required action area. These two dives require that the adult fish ladder exit and Diffuser 14 intake be bulkhead closed and tagged out for up to 65 hours, thus closure of ladder operations. Options for continued ladder operation at FFDRWG on 21 AUG 2014 and SCT on 4 SEP 2014 included dropping ladder inflow to orifice flow and interrupted ladder closure on a daily time step or for two 3 day periods of time with a 2-3 day period of ladder operation to facilitate passage of those adults blocked for the previous 3 days. Further discussion with LGR Project and Dive Coordinators require complete ladder closure for up to 65 hours, in addition to the benefit of limiting the required number of times for which a biologist crew would need to perform fish salvage throughout the ladder. Options discussed were: 1) April work in-water window instead of May, 2) June in-water work window instead of May, 3) two non-continuous 30 hour closure periods either within 2014 June in-water work window, or 4) perform one-half of the tasks (either pipe extensions or “chimney”) in Year 1 (2015) with a second year of renting submerged pumps, then delay the second remaining task until Year 2 (2016), 5) doubling up the work schedule for 2 shifts of 10 hour working dives each day for 3 days (likely requiring 2 dive crews), or 6) doubling up 2 dive crews to dive during the single 10 hour daytime shift simultaneously working on both the pipe extensions and the “chimney” each day for 3 days.

Type of outage required- Requesting ESA Coordination with discussion on complete total adult fish ladder closure by bulkhead closure of the exit at surface water elevation to about 6 feet deep, plus valve and bulkhead closure of the Diffuser 14 intake at 15 feet deep for 3 continuous days during either the second or third week of June 2015.

Impact on facility operation – LGR Project would be required to bulkhead close the adult ladder exit, Diffuser 14 intake, and ladder entrances for 3 continuous days followed by a fish salvage of any remaining salmonids trapped within the ladder. In addition, the adult trap water supply would be terminated, thus eliminating any trapping and tagging of adult salmonids for on-going or scheduled research and management projects for the same 3 days.

Dates of impacts/repairs – 8, 9, 10 June 2015 or 15, 16, 17 June 2015.

Length of time for repairs – 65 hours compressed into 30-35 hours within 3 working days.

Expected impacts on fish passage.

Juvenile salmonid/Smolt passage:24 APR – 29 MAY construction could overlap with ~80% run (between the 10-90% bounds in FPP and DART) of juvenile yearling Chinook, steelhead, coho, and sockeye passing through summer spill of 20 kcfs @ LGR (16-28% spill for 70-120 kcfs inflow). Although very high juvenile passage overlap, location of pipe install at LGR ladder should not other than consequential impact juvenile salmonid passage.

Adult Fish passage: Lower Granite has a single ladder on the southshore, thus no option of directing adult fish to an alternate ladder for passage. A 3 day passage blockage of adult spring and summer Chinook during the first 2 weeks of June 2015 could block 500-750 fish per day (1500-2250 adult Chinook total) to remain in the tailrace. The magnitude of 1500-2250 adult spring and summer Chinook blocked from ladder passage is similar to what has occurred during in-season periods of 60-80 kcfs flow patterning at Little Goose’s single ladder, when a 2-3 day closure process of the TSW with shifting to a uniform spill pattern has been required to successfully get delayed adult Chinook to pass. If were to remain with a 3-6 day ladder closure in May there would be a greater concern for adult Chinook passage (blockage of between a couple hundred and 3800 daily peaks of Chinook equating up to 10 yr average of 51.8% of run (42.2-63.5%)). If scheduled to end the ladder outage by 1 May, essentially an April in-water work window, then could risk a 2001-type water year condition distribution of adult Chinook passage affected. This could be a major risk during a low flow year by affecting the blockage of over 9000 adult Chinook passing per day if construction would have occurred during the last week of April in 2001. Whereas, an in-water work window during the first week of May would affect about 800 to 3200 adult Chinook passing per day. A scheduled 3-6 day ladder closure for construction during May would be a minor concern for adult wild steelhead passage with relatively low risk of impact (10 yr 8.4% (1.8-6.4%)). No concern for sockeye because have not started passage at Lower Granite until mid- to late-June.

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LGR Adult Chinook Passage: 42-63% passage overlap with pro-posed ladder outage window, best window 1 APR-23 APR or 2nd week of June.

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LGR Adult Wild Steelhead Passage: 2-8% passage overlap with proposed ladder outage window, best window 17 MAY-21 JUN.

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LGR Adult Sockeye Passage: virtually 0% passage overlap with proposed ladder outage window, best window is prior to 24 June.

Comments from agencies:

-----Original Message-----From: Morrill, Charles (DFW) [mailto:Charles.Morrill@dfw.wa.gov] Sent: Tuesday, September 09, 2014 1:44 PMTo: Moody, Gregory P NWWCc: Morrill, Charles (DFW)Subject: [EXTERNAL] RE: MOC Official Coordination: 14 LWG 13 LWG Ladder Temperature Improvement Construct.docx (UNCLASSIFIED)

Thanks Greg,

no comments at this point .. discussing with other managers ...

Charlie

Final results:Please email or call with questions or concerns.

Thank you,

Chris Pinney

Fishery Biologist

OFFICIAL COORDINATION REQUEST FOR NON-ROUTINE OPERATIONS AND MAINTENANCE

COORDINATION TITLE- 13 LWG 022 Lower Granite Fish Screen Slot PlugsCOORDINATION DATE- 10 December 2013PROJECT- Lower GraniteRESPONSE DATE- FPOM December 2013

Description of the problemThe Lower Granite JBS and JFF upgrades include the widening of the juvenile fish collection channel from 6 ft. to 9.5 ft. The widening of the collection channel will require the placement of a plug in the upper fish screen slot for structural support (Figure 1). The fish screen slots and Wagner Horns were originally constructed for fish passage but were abandoned. Exclusion screens were placed in the bottom of the fish screen slots and Wagner Horns and ESBS screens were placed in the bulk head slots for fish passage. Construction of only the upper plug will create limited access to the exclusion screens in the fish screen slot and Wagner Horns with access limited to divers or remote operated vehicles. The USACE proposes to construct plugs in the bottom of the fish screen slots and Wagner Horns as part of the JFF/JBS upgrades. The bottom plugs will be constructed in 2014 and 2015 and will coincide with annual maintenance of turbine units. The proposed plugging of the fish screen slots will require the removal of the exclusion screens, filling the screens with concrete and lowering the screens back into the fish screen slots. The Wagner Horns will have the exclusion screen removed and a precast plug will be anchored in the bottom of the slot. Following the placement of the plugs in the fish screen slots and the Wagner Horns, fish will be removed by dipping the fish screen slot to remove as many fish as possible before the tremie concrete work begins.

Type of outage requiredUnit outages will be required to install plugs in the fish screen slots and Wagner Horns. The anticipated timing of the fish screen slot bottom plugs and Wagner Horn plugs would coincide with annual unit outages. The overall timing of the plug construction is approximately 21 days per unit.

Impact on facility operationImpacts to facility operations should be minimal as the project will be concurrent with annual unit outages. Dates of impacts/repairsAugust 2014 to February 2015

Length of time for repairsApproximately 21 days per unit

Expected impacts on fish passageNo impacts anticipated as the project will be conducted during annual unit outages.

Figure 1. Overview of the proposed plugs in the fish screen slots and Wagner Horns. The bottom plugs would be installed first with the upper plugs being constructed in the dry.

OFFICIAL COORDINATION REQUEST FOR NON-ROUTINE OPERATIONS AND MAINTENANCE

COORDINATION TITLE - 13 LWG 22 Lower Granite Fish Screen Slot PlugsCOORDINATION DATE – 24 December 2013 PROJECT- Lower GraniteRESPONSE DATE – January FPOM Meeting

Description of the problem: The Lower Granite JBS and JFF upgrades include the widening of the juvenile fish collection channel from 6 ft. to 9.5 ft. The widening of the collection channel will require the placement of a plug in the upper end of the fish screen slot for structural support (see Figure 1 below). The fish screen slots and Wagner Horns were originally constructed for fish passage but were abandoned. Exclusion screens were placed in the bottom of the fish screen slots and Wagner Horns and ESBS screens were placed in the bulk head slots for fish passage. Construction of only the upper plug will create limited access to the exclusion screens in the fish screen slot and Wagner Horns with access limited to divers or remote operated vehicles. The USACE proposes to construct plugs in the bottom of the fish screen slots and Wagner Horns as part of the JFF/JBS upgrades. The bottom plugs will be constructed in 2014 and 2015 and will coincide with annual maintenance of turbine units. The proposed plugging of the fish screen slots will require the removal of the exclusion screens, filling the screens with concrete and lowering the screens back into the fish screen slots. The Wagner Horns will have the exclusion screen removed and a precast plug will be anchored in the bottom of the slot. Following the placement of the plugs in the fish screen slots, fish will be removed by dipping the fish screen slot to remove as many fish as possible before the tremie concrete work begins. Fish removed from the fish screen slot will be transported below the dam for release.

Type of outage required: Unit outages will be required to install plugs in the fish screen slots and Wagner Horns. The anticipated timing of the fish screen slot bottom plugs and Wagner Horn plugs would coincide with annual unit outages. The overall timing of the plug construction is approximately 21 days per unit.

Impact on facility operation: Impacts to facility operations should be minimal as the project will be concurrent with annual unit outages. A gatewell dipping operation is anticipated to be necessary to remove any fish from the fish screen slot following the placement of the plugs, and will coordinated with Project fisheries and SMP staff or if necessary a private contractor.

Since outages are planned after the peak of spring run-off, all turbine units will be available to reduce the impacts of high river flows and the production of excess dissolved gasses.

Dates of impacts/repairs:Unit 4: 7/7/14 to 8/4/14Unit 6: 8/4/14 to 9/1/14Unit 5: 9/1/14 to 9/29/14Unit 3: 9/29/14 to 11/3/14Unit 2: 11/10/14 to 12/8/14Unit 1: 12/8/14 to 1/5/15

Length of time for repairs: The proposed actions will be approximately 21 days per plug and the scheduled annual maintenance of the units is 4 weeks for units 1, 2, 4, 5, & 6 with unit 3 outage being 5 weeks.

Expected impacts on fish passage: Limited impacts on fish passage as the construction will be conducted during annual unit outages. Following the placement of the plugs, fish will be dipped and transported below the dam for release (Table 1). Adult passage is not expected to be affected by the short outage maintenance operation on each unit because other nearby units will be available. Turbine units 1 and 2 will be available to provide attraction flow to the south shore entrances during the peak of the adult steelhead run.

Table 1 – Collection counts at Lower Granite Juvenile Fish Facility during 2006 to 2013.

Year July August September October2006 63,425 1,841 2,107 4,2192007 26,752 2,056 1,124 10,4072008 760,668 21,047 9,220 8,7312009 71,258 3,044 2,002 2,1152010 86,885 8,907 8,436 11,4362011 117,828 6,498 14,307 5,7212012 70,808 8,121 6,443 12,2552013 55,912 13,613 12,455 24,294

Comments from agencies

Final results

Please email or call with questions or concerns.

John BaileyFishery Biologist, Operations DivisionWalla Walla DistrictU.S. Army Corps of Engineers201 North Third AvenueWalla Walla, WA 99362-1876

OFFICIAL COORDINATION REQUEST FOR NON-ROUTINE OPERATIONS AND MAINTENANCE

COORDINATION TITLE – 15 LWG 001 ower Granite Fish Screen Slot Plugs Schedule changeCOORDINATION DATE – February 6, 2015PROJECT- Lower Granite Lock and DamRESPONSE DATE – February 12, 2015 (FPOM Mtg)

Description of the problem: The Lower Granite JBS and JFF upgrades include the widening of the juvenile fish collection channel from 6 ft. to 9.5 ft. The widening of the collection channel will require the placement of a plug in the upper end of the fish screen slot for structural support (see Figure 1 below). The fish screen slots and Wagner Horns were originally constructed for fish passage but were abandoned. Exclusion screens were placed in the bottom of the fish screen slots and Wagner Horns and ESBS screens were placed in the bulk head slots for fish passage. Construction of only the upper plug will create limited access to the exclusion screens in the fish screen slot and Wagner Horns with access limited to divers or remote operated vehicles. The USACE proposes to construct plugs in the bottom of the fish screen slots and Wagner Horns as part of the JFF/JBS upgrades. The bottom plugs will be constructed in 2014 and 2015 and will coincide with annual maintenance of turbine units. The proposed plugging of the fish screen slots will require the removal of the exclusion screens, filling the screens with concrete and lowering the screens back into the fish screen slots. The Wagner Horns will have the exclusion screen removed and a precast plug will be anchored in the bottom of the slot. Following the placement of the plugs in the fish screen slots, fish will be removed by dipping the fish screen slot to remove as many fish as possible before the tremie concrete work begins.

Update: The construction of the fish screen slot and Wagner Horn plugs began in October 2014 on Unit 1 with an anticipated completion approximately 21 days following the start of the construction. Numerous delays pushed the completion of Unit 1 until early February 2015. The contractor has moved into Unit 3 (January 2015) with an anticipated completion by the middle of February. The USACE is proposing to move into Unit 2 with and anticipated completion of March 25, 2015. The completion of Unit 1 and Unit 3 would allow Lower Granite to run either Unit 1 or Unit 3 as priority units during the Unit 2 outage. Units 5, 6, and 4 would be completed during the next annual maintenance period starting July 7, 2015 and being completed October 5, 2015.

Anticipated schedule for Fish Screen Slot Plugs (2/5/15)o Completion of Unit 1 and Unit 3 during the week of February 9.o Contractor would move into Unit 2 with a completion of March 25, 2015

Type of outage required: Unit outages will be required to install plugs in the fish screen slots and Wagner Horns. The anticipated timing of the fish screen slot bottom plugs and Wagner Horn plugs would coincide with annual unit outages.

Update: The completion of the fish screen slot plugs may be delayed until the next scheduled annual unit maintenance period (See Dates of Impacts/Repairs below).

Impact on facility operation: Impacts to facility operations should be minimal as the project will be concurrent with annual unit outages. A gatewell dipping operation is anticipated to be necessary to remove any fish from the fish screen slot following the placement of the plugs, and will coordinated with Project fisheries and SMP staff or if necessary a private contractor.

Since outages are planned after the peak of spring run-off, all turbine units will be available to reduce the impacts of high river flows and the production of excess dissolved gasses. Dates of impacts/repairs:Planned Unit outages for 2015 are as follows:Unit 5: 7/6/15 to 8/3/15 (Annual Maintenance)Unit 6: 8/3/15 to 8/31/15 (Annual Maintenance)Unit 4: 8/31/15 to 10/5/15 (Unit 4 Overhaul)

Length of time for repairs: The proposed actions will be approximately 21 days per plug and the scheduled annual maintenance of the units is 4 weeks for units 1, 2, 4, 5, & 6 with unit 3 outage being 5 weeks.

Update: The original proposal was to complete plugs (slots A, B, and C) in 21 days with the first set of plugs (Unit 1) requiring approximately 4 months to complete. The second set of plugs (Unit 3) is estimated to be completed in 15 days.

Expected impacts on fish passage: Limited impacts on fish passage as the construction will be conducted during annual unit outages. Following the placement of the plugs, fish will be dipped and transported below the dam for release (Table 1). Adult passage is not expected to be affected by the short outage maintenance operation on each unit because other nearby units will be available. Turbine units 1 and 2 will be available to provide attraction flow to the south shore entrances during the peak of the adult steelhead run.

Table 1 – Collection counts at Lower Granite Juvenile Fish Facility during 2006 to 2013.

Year July August September October2006 63,425 1,841 2,107 4,2192007 26,752 2,056 1,124 10,4072008 760,668 21,047 9,220 8,7312009 71,258 3,044 2,002 2,1152010 86,885 8,907 8,436 11,4362011 117,828 6,498 14,307 5,7212012 70,808 8,121 6,443 12,2552013 55,912 13,613 12,455 24,294