DISPOSITION OF 2022 SORs

D2022-1   D2022-2-BON-B2CC   D2022-FWS#1   D2022-4   D2022-C1   D2022-C2  

 

D2022-1   Top of Page
12-January-2022 2022-1 FPAC Vice-Chair Clarifying the frequency of zero-generation operations of the four Lower Snake River dams
1. SOR Request SPECIFICATIONS:
We request that the following clarification be used to guide the frequency of zero-generation operation implementation:

• Zero-generation at any single dam on the Lower Snake River will be implemented no more than 1 out of every 3 to 5 days, between the date of initiation (see SOR 2021-6) until the last day of February.

JUSTIFICATION:
The Term Sheet for Stay NWF v. NMFS, ECF 2411-1 (3:01-cv-00640-SI) includes implementation of zero generation operations per date and abundance criteria described in SOR 2021-6. These criteria were met on December 17 in 2021. Zero generation operations post December 17th should be consistent with anticipated usage of “one out of every 3 to 5 days at each project” as described in the 2020 CRSO BA p 2-63 (pdf p. 98):

“Between October 15 and February 28, when power market conditions warrant and when river conditions make it feasible, power generation at Snake River projects may cease during nighttime hours, most commonly implemented between 2300 and 0500 hours when demand for power is lowest and other renewable resources are generating surplus power (or both). This operation will end no later than 2 hours before dawn between October 15 and November 30. During the operation between December 15 and February 28, daytime hours will no longer be excluded from this operation, and up to 3 hours of daytime cessation will be part of the Proposed Action. This shift in current operation would allow operators to save water in low demand periods to use for hydropower generation during higher demand periods. The timing and need for ceasing power generation during this period of time is difficult to predict. However, based on previous operations between December 15 and February 28 and during nighttime hours only, Bonneville estimates the use of this operation may occur one out of every 3 to 5 days at each project. See the WMP21 for additional details.” (emphasis added)

Actual implementation by Bonneville Power Administration (BPA) during winter 2020-2021 or winter 2021-2022 does not conform with a reasonable interpretation of “one out of every 3 to 5 days” (i.e., 33% - 20% of days). Rather, implementation has been as much as every day between December 22, 2021 and January 8, 2022. At past TMT meetings, BPA has repeated that their intent was to match historical usage of this operation, but the Proposed Action and other guiding documents do not adequately describe historical usage. Instead, the language refers to one out of every 3 to 5 days (see excerpt from 2020 BA above). Operating in extreme exceedance of this description is inconsistent with the Proposed Action.
2. Requester(s) Columbia River Inter-Tribal Fish Commission/Confederated Tribes of the Umatilla Indian Reservation, Nez Perce Tribe, Spokane Tribe of Indians, Yakama Nation, Washington Department of Fish and Wildlife, and Oregon Department of Fish and Wildlife
3. TMT Recommendation January 19, 2022, TMT Meeting.

Tom Lorz, CRITFC, reported on SOR 2022-1, which requests clarification on the frequency of zero-generation operations of the four Lower Snake River dams (posted to the TMT website). Specifically, it requests language clarification to include that zero generation at any single dam on the Lower Snake River will be implemented no more than 1 out of every 3-5 days, between the date of initiation until the last day of February.

The BiOp included a broader date range for the operation, which was adjusted in the Agreement on 2022 Operations. Tom shared that from the SOR signatories’ perspective, the sideboards of the operation need to be clarified to address what partners are seeing as inconsistencies between the description analyzed in the BiOp and what is being implemented.

TMT Members were polled on the SOR, with some providing additional rationale for their responses:

o NOAA = Abstain. NOAA evaluated the operation based on historical implementation in recent years and assessment of biological risk; NOAA did not interpret the proposed action as specifying that the operation will not be done on consecutive days or more in 1 out of every 3-5 days. As of today’s date, BPA’s implementation is within historic range of usage and within the allowable range described in SOR 2002-22, and recent water management plans; NOAA doesn’t anticipate any risk to juvenile fall Chinook or adult steelhead beyond those already considered in the BiOp. NOAA will continue to monitor implementation in-season and post-season.

o OR = Supports. Oregon supports the SOR and believes it important because it revisits past discussions on this operation. There is uncertainty surrounding evaluation, sideboards, and decision-making, that, from Oregon’s perspective, do not provide support for the protection of listed species. Oregon believes the SOR addresses what would be expected to occur based on guiding federal documents, and that current activity is out of the operational sideboards.

o WA = Supports. Washington believes that clarification and further discussion on the operational expectations are needed and will benefit all involved.

o Umatilla Tribe = Supports. No additional comments.

o Reclamation = Abstain. No additional comments.

o Corps = Supports. No additional comments.

o USFWS = Abstain. USFWS abstained and is reserving judgement until after new video monitoring data via the Corps is analyzed from the fish ladders at Lower Monumental and Little Goose Dams. When USFWS evaluated this operation for the BiOp, the focus was on bull trout, which have very limited data during the winter months due to lack of monitoring.

o ID = Abstain. Idaho generally agrees that it would be helpful to clarify the language in the proposed action to better reflect how the AAs intend/expect to operate.

o MT = Abstain. Montana wants to further understand the biological implications of the operation and requested more information on this.

o BPA = Abstain. No additional comments.

o The Nez Perce and Spokane Tribes were signatories to the SOR; however, were not present to provide a polling response/rationale during the meeting. The Colville, Kootenai, and Warm Springs Tribes were not present to register a polling response.
4. AA Decision January 19, 2022, TMT Meeting.

The Action Agencies need to vet the SOR internally and requested a TMT meeting be added to the calendar for January 26 at 9:00AM. At that time, the AAs will provide a response to the SOR.

o ACTION: Jonathan Ebel, ID & FPAC Chair, will follow up with Brian Marotz, MT, and provide additional information regarding the operation’s biological impacts, with the caveat that the basin’s monitoring structure is not operating right now, so behavior for overwintering fish in the system is unknown.

o ACTION: The AAs will meet internally to discuss the SOR, with the intention of providing a response on January 26.

o ACTION: A TMT meeting will be scheduled for January 26 at 9:00AM.

January 26, 2022, TMT Meeting.

Following the introduction and discussion of SOR: 2022-1 at the January 19 TMT meeting, Action Agencies requested additional time to discuss the SOR internally and prepare a response. The SOR sought further clarification on zero generation operations of the four Lower Snake River dams.

Action Agency Response. Tony Norris BPA, reported the official response from AAs (posted to the TMT website). AAs estimate the expected future use of zero generation on the lower Snake River projects to be consistent with the historical use during the period since 2004, and as modified in the litigation stay agreement (see Term Sheet link below). This use can range from several consecutive days of use to very little use across the 4 Lower Snake River projects during the period of available days and hours as described in the Water Management Plan (WMP).

Regarding the final sentence of the Conclusion within the AAs’ response, it was stated that the AAs, “will not entertain future SORs or requests that seek only to revisit prior operations agreed to in the Term Sheet,” Tony clarified that this does not preclude SORs that have new information or are in response to in-season conditions that could benefit from adaptive management. However, AAs will not entertain SORs that revisit prior operations agreed to in the Term Sheet.

Additional TMT Questions & Comments. It was clarified that the SOR did not request a change in operation, instead, it requested clarifying language on the sideboards that AAs anticipate for the frequency of implementation of zero generation operations. The intention of the clarification is to help manage expectations of the frequency of the operation. Co-managers were appreciative of the clarification that the AAs’ response provided, however, there were still some areas that they felt needed more clarity

Charles Morrill, WA, noted that specifically co-managers are looking for clarification on the existing language (in the AAs’ Proposed Action) of “1 out of every 3-5 days,” and sideboards, emphasizing that from some co-managers’ perspective, this statement does not accurately reflect what is being implemented. Tony noted that zero generation is used with flexibility when power market and river conditions are conducive to its use. He noted that from the AAs’ perspective, it is within historical range to use zero generation operations on consecutive days, and they do not have a daily limit. Jay Hesse, Nez Perce Tribe, acknowledged that BPA’s scale for measuring is multi-year averages, which Tony confirmed. Jay expressed that from the Nez Perce Tribe’s perspective, there are differing descriptions in the various guiding documents and revising language would be helpful.

Claire McGrath, NOAA, also noted that in their analysis, NOAA assumed that zero generation operations would be consistent with historical use and will continue to be applied when market and river conditions warrant. This assumes that market and river conditions do not experience any significant changes - which NOAA has not seen to date.

It was noted that the effects of the operation on the river ecosystem is a concern for fish managers, however, they are unable to evaluate effects because there are no monitoring systems in place. However, fish managers are concerned with ponding the riverine system, as it is generally bad for fish movement. (Jay pointed out that this SOR does not address the biological effects and Claire McGrath, NOAA, pointed those interested to the September 15, 2021 TMT meeting minutes for description of how NOAA analyzed potential effects.)

There was discussion on the condition of the river during zero generation operations. Tony noted that the river is still flowing, as the slope and length of the system allows for water to stop passing a project but continue to flow downstream to the next project. Jay reflected that water flow at the project stops during the operation, as does fish passage through the project.

Tony clarified that AAs are not intending to shut down technical discussions on operations, and that if new information or in-season conditions warrant operational changes, SORs will be considered. Pre-coordination on SORs may be necessary to ensure that the intent is clear for all.

ACTION: Tony will relay to the BPA Policy team the input that he has heard from TMT partners regarding further clarification and concerns with the Conclusion. If there are additional language changes, Tony will bring that back to TMT.

Additional information regarding this meeting may be found in the meeting minutes on the following website.

https://pweb.crohms.org/tmt/agendas/2022/0126_Minutes.pdf
5. IT Recommendation  
6. AA decision (post IT)  
7. Actual Implemented Operation January 26, 2022, TMT Meeting.

Tony clarified that AAs are not intending to shut down technical discussions on operations, and that if new information or in-season conditions warrant operational changes, SORs will be considered. Pre-coordination on SORs may be necessary to ensure that the intent is clear for all.

ACTION: Tony will relay to the BPA Policy team the input that he has heard from TMT partners regarding further clarification and concerns with the Conclusion. If there are additional language changes, Tony will bring that back to TMT.
8. If different from AA decision, why?  
D2022-2-BON-B2CC   Top of Page
15-March-2022 2022-2-BON-B2CC Jonathan Ebel, FPAC Chair Operation of the Bonneville Corner Collector for Spring Creek NFH Emergency Release
1. SOR Request SPECIFICATIONS:
We are requesting that the Bonneville Corner Collector (B2CC) remain open until 13:00 March 20th to help improve the dam passage survival of the emergency release of 10.8 million fall Chinook from Spring Creek NFH.

JUSTIFICATION:
Spring Creek NFH has made an emergency early release of all 10.8 million fall Chinook due to an outbreak of bacterial gill disease, with the last group of ~5.6 million fish released on March 14th. Since this release was prior to the normal spring spill period, most of these fish would normally be passing through powerhouse passage routes.

The dates of the emergency release (March 11th-14th) happened to coincide with a period where the B2CC has been open most of the time due to lack of turbine capacity. However, the B2CC is likely to close on March 18th when four turbines at BON PH2 that have been out of service due to maintenance are scheduled to return to service.

Tagging studies show that 90% of Spring Creek NFH fall Chinook pass Bonneville Dam anywhere from one to four days after release, depending on the year (FPC Memo 42-21). However, many of those releases occurred in April and May during the spring spill period, and several studies have shown that early migrating smolts have longer travel times than later migrating smolts, so there is a fair amount of uncertainty around the exact travel time of this release.

We are requesting that the B2CC remain open until 13:00 March 20th to help improve the dam passage survival of this emergency release, as the B2CC has a very high juvenile passage survival rate (Mean: 99%, Range 97.5-100%), based on acoustic tag studies. This extension would keep the B2CC open a full six days since the last release from Spring Creek NFH and should expand the fraction of fish that have this passage route as an option to well above 90%.
2. Requester(s) US Fish and Wildlife Service, Columbia River Inter-Tribal Fish Commission/Confederated Tribes of the Umatilla Reservation, Idaho Department of Fish and Game, Washington Department of Fish and Wildlife, Oregon Department of Fish and Wildlife, and Nez Perce Tribe.
3. TMT Recommendation March 16, 2022, TMT Meeting.

Jonathan Ebel, FPAC Chair, presented SOR 2022-2, which requests that the Bonneville Dam Powerhouse 2 Corner Collector (B2CC) remain open until 13:00 on March 20 to help improve the dam passage survival of the emergency release of 10.8 million juvenile fall Chinook from Spring Creek National Fish Hatchery. The emergency release is due to a disease outbreak that infected some, but not all the fish. Dave Swank, USFWS, noted that this request was being made to provide the best possible passage survival for these fish and keeping the B2CC open until this date should provide well over 90% passage of the release. Tom Lorz, CRITFC, noted that not all fish were diseased. There were five ponds of fish (approximately 1.5 million fish) in relatively good condition; however, the decision was made to release all the fish at the same time to avoid further contamination. Tom noted that typically the B2CC would have been open at this time if the kelt criteria were met.

TMT Members were polled on the SOR:

o NOAA = Supports. No additional comments.

o OR = Supports. OR appreciates the support for this operation.

o WA = Supports. No additional comments.

o Umatilla Tribe = Supports. No additional comments.

o Reclamation = Supports. No additional comments.

o Corps = Supports. No additional comments.

o USFWS = Supports. USFWS appreciates the Corps and BPA support for the operation during this highly unusual event at the hatchery.

o ID = Supports. No additional comments.

o MT = Supports. No additional comments.

o Nez = Supports. No additional comments.

o BPA = Supports. No additional comments.

o The Colville, Kootenai, Spokane and Warm Springs Tribes were not present to register a polling response.
4. AA Decision March 16, 2022, TMT Meeting.

The Corps and BPA will implement the SOR as described.

? ACTION: The B2CC will remain open until 13:00 March 20, after which the B2CC will operate as described in the 2022 Fish Passage Plan (FPP).

5. IT Recommendation  
6. AA decision (post IT)  
7. Actual Implemented Operation March 16, 2022, TMT Meeting.

ACTION: The B2CC will remain open until 13:00 March 20, after which the B2CC will operate as described in the 2022 Fish Passage Plan (FPP).

8. If different from AA decision, why?  
D2022-FWS #1   Top of Page
06-May-2022 2022-FWS #1 Christopher Swanson, State Supervisor, U.S. Fish and Wildlife Service, Idaho Fish and Wildlife Office 2022 Libby Dam Releases for Sturgeon and Bull Trout Flows
1. SOR Request SPECIFICATIONS:
Based on the U.S. Fish and Wildlife Service’s (Service) July 24, 2020, Biological Opinion on Columbia River System Operations and Maintenance, and the U.S. Army Corps of Engineers (Corps) May final April-August volume runoff forecast of 6.74 million acre-feet (MAF) (Flow Plan Implementation Protocol Technical Team) Final Flow Plan for 2022 Sturgeon Operations at Libby Dam, dated (May 6, 2022), we are within a Tier 4 operations year for Kootenai River white sturgeon. The minimum recommended release volume for sturgeon conservation in a Tier 4 year is 1.18 MAF and we recommend the following procedures for discharge of at least this minimum volume from Libby Dam.

The precise means that will be utilized to meet these objectives are dependent on realtime conditions and in-season water management. Given these uncertainties, the Technical Team has developed the following guidelines for sturgeon operations in 2022:

• Libby Dam discharge will increase to full powerhouse capacity (~25,000 cfs) following BiOp ramping rates on May 16. After ~22 days at full powerhouse capacity, Libby Dam discharge will be reduced to 20,000 cfs for ~7 days, and then reduced to 9,000 cfs over ~9 days following BiOp ramping rates - at which time the sturgeon augmentation volume will be exhausted.

•• Bonners Ferry Stage > 1,760’ MSL: ~16 days

•• 30,000+ cfs @ Bonners Ferry: ~30 days

• Selective Withdrawal System (SWS) gates at Libby Dam above elevation 2,326 feet mean sea level (MSL) will be installed immediately prior to, and during, the peak flow period, with the objective of passing the warmest water available in the forebay (surface and sub-surface) as it becomes available. Release of the warmest water possible from Libby Dam, in combination with lower volume of release, may allow the Kootenai River temperature to increase to appropriate temperatures at Bonners Ferry (9-10+°C) during the receding limb of the hydrograph to trigger spawning, and support incubation and proper early larval development while stimulating primary production to support food web dynamics.

• Selective Withdrawal System (SWS) gates at Libby Dam above elevation 2,326 feet mean sea level (MSL) will be installed immediately prior to, and during, the peak flow period, with the objective of passing the warmest water available in the forebay (surface and sub-surface) as it becomes available. Release of the warmest water possible from Libby Dam, in combination with lower volume of release, may allow the Kootenai River temperature to increase to appropriate temperatures at Bonners Ferry (9-10+°C) during the receding limb of the hydrograph to trigger spawning, and support incubation and proper early larval development while stimulating primary production to support food web dynamics.

• After the sturgeon flow augmentation volume has been exhausted, decrease discharge at Libby Dam towards stable summer flows, following BiOp ramping rates, to no less than bull trout minimum flows (9,000 cfs in Tier 4).

• Flood risk reduction operations supersede sturgeon flow augmentation, and dam managers will coordinate operations with regional sturgeon managers. The sturgeon augmentation discharge may be extended for additional days if the Corps elects to provide volume in excess of the minimum volume requirement in the 2020 BiOp to control the refill rate of Libby Dam.

• Additional recommendations may be provided as water supply forecasts are updated in order to provide stable or gradually declining discharge through the end of August following ramping rates and minimum flow guidelines in the 2020 BiOp. JUSTIFICATION:
The objective of the 2022 sturgeon flow augmentation operation in this SOR is to provide a period of peak river stage/flow during the spring freshet, and to concurrently provide a stable to rising thermograph in the river as the operation concludes. The peak Libby Dam discharge (25,000 cfs), timed to coincide with peak downstream tributary (local) run-off, is intended to provide: 1) cues for sturgeon to migrate further upstream from their staging areas, and then cues to spawn on the descending limb of the hydrograph (receding flow, warming water), with the overall goal of providing conditions that will enhance the likelihood for sturgeon to migrate to, and spawn over, rocky substrates that exist upstream of Bonners Ferry; and 2), connectivity to the floodplain, and partial inundation of, Nimz Ranch, an off-channel Kootenai Tribe of Idaho-owned habitat downstream of Shorty’s Island, for the purposes of allowing for spatially and temporally normative ecological processes in support of primary and secondary productivity for larval sturgeon and other species.

The operating parameters outlined in this SOR are intended to provide guidance on how to provide optimal conditions for Kootenai sturgeon migration, spawning, incubation, and rearing. Previous years’ operations have shown that conditions at Libby Dam and in the Kootenai River basin can change rapidly. Recognizing this, the exact shape of the operation will need to be developed and modified in-season as more is known. The inseason coordination will occur via the Kootenai River Sturgeon Flow Plan Implementation Protocol Team with a final recommendation coordinated through the Action Agencies and the Technical Management Team.
2. Requester(s) U.S. Fish and Wildlife Service, Idaho Fish and Wildlife Office, on behalf of the Libby Biological Opinion Policy Group
3. TMT Recommendation May 11, 2022, TMT Meeting.

The, USFWS, reported on the annual SOR (FWS #1) for Libby Dam releases for Kootenai River white sturgeon and bull trout flows (posted to the TMT website). It is part of the proposed action from the 2020 BiOp. The operation aims to provide a peak river stage/flow during the spring freshet to cue sturgeon to spawn upstream of Bonners Ferry, provide connectivity to the floodplain and partially inundate Nimz Ranch habitat, and to concurrently provide a stable to rising thermograph in the river as the operation concludes.

For further background context and updates the Corps presented on 2022 Libby Dam Sturgeon Operations (posted on the TMT website). The Corps also reviewed the May water supply forecast, BiOp objectives, and a summary of planned refill operations for the project. The sturgeon augmentation flow is planned to start on May 16, ramping up discharges from Libby to 25 kcfs (powerhouse capacity) and maintain the pulse for approximately 22 days, followed by a period at 20 kcfs. Discharge will decrease after the pulse to summer flat flow following the BiOp ramping rates.

In response to a query, the Idaho Department of Fish and Game, noted there are a little over 100 sturgeon with active tags, although it’s not known how many of those will make spawning migration yet; about 8 have been detected above Shorty’s Island so far.

TMT Members were polled on the SOR, with some providing additional rationale for their responses:

o NOAA = Supports. NOAA appreciated the efforts to support sturgeon spawning.

o OR = Supports. No additional comments.

o WA = Supports. Washington agreed with NOAA’s statement.

o Kootenai Tribe of Idaho = Supports. Kootenai Tribe greatly appreciated everyone’s support for resident fish in the upper basin.

o Confederated Tribes of the Colville Reservation = No Objection. No additional comments.

o Confederated Tribes of the Umatilla Indian Reservation = No Objection. No additional comments. Umatilla Tribes wished the operation good luck and success.

o Reclamation = Support. No additional comments.

o Corps = Supports. The Corps expressed thanks to all parties.

o USFWS = Support. USFWS thanked all parties for their continued support of the SOR and operation.

o ID = Support. No additional comments.

o MT = Support. MT was happy with the repetitive experimenting ramping down to elicit spawning.

o Nez Perce Tribe = Support. No additional comments.

o Confederated Tribes of Warm Springs = Support. No additional comments.

o Bonneville = Support. No additional comments.

o The Spokane Tribe of Indians was not present to register a polling response.
4. AA Decision May 11, 2022, TMT Meeting.

The Action Agencies plan on implementing the SOR as described and presented today, and look forward to the results of the operation.

5. IT Recommendation  
6. AA decision (post IT)  
7. Actual Implemented Operation January 26, 2022, TMT Meeting.

Tony clarified that AAs are not intending to shut down technical discussions on operations, and that if new information or in-season conditions warrant operational changes, SORs will be considered. Pre-coordination on SORs may be necessary to ensure that the intent is clear for all.

ACTION: Tony will relay to the BPA Policy team the input that he has heard from TMT partners regarding further clarification and concerns with the Conclusion. If there are additional language changes, Tony will bring that back to TMT.
8. If different from AA decision, why?  

 

D2022-4   Top of Page
17-May-2022 2022-4 Jonathan D. Ebel, Idaho Department of Fish and Game Palisades Powerhead Water delivery for flow augmentation in 2022
1. SOR Request SPECIFICATIONS:
We request that the remaining Palisades Powerhead water in the Bureau of Reclamation reservoirs of the Snake River system above Milner Dam (53.3 kaf) be held in the storage system in 2022.

JUSTIFICATION:
Current water supply forecasts show continued drought in the Snake River basin, particularly in east Idaho, northwest Wyoming, and across the Snake River Plain. As a result, the Bureau of Reclamation will be unable to release the full volume of flow augmentation water described in the 2007 Upper Snake River Biological Assessment and 2008 Upper Snake River Biological Opinion (i.e., 427-487 kaf).

Extreme hot and dry conditions in 2021 resulted in November 01 active storage carryover in the reservoirs of the Snake River above Milner of approximately 827 kaf. The current Bureau of Reclamation May – July forecast for the Snake River above Heise is 2.2 MAF, or 76% of the 30 year average. Compounding the impact of low active carryover from water year 2021 was the release of ~94 kaf of Palisades Powerhead water in 2021 – a spring delivery in May 2021 and a summer delivery in late June – early July 2021 to meet federal salmon flow augmentation obligations. Depending on summer 2022 conditions, system storage in late summer and early fall 2022 may reach extremely low levels with potential serious, long-term consequences for resident fishes, particularly native fishes in the South Fork Snake River. Keeping Palisades powerhead water in the system rather than releasing it for salmon flow augmentation would allow for higher water levels in Palisades Reservoir and other reservoirs in late summer because it cannot be used for irrigation.

Potential impacts of not implementing the requested operation to Yellowstone Cutthroat Trout in the South Fork Snake River

The South Fork Snake River below Palisades Reservoir supports one of the few remaining largeriver populations of Yellowstone Cutthroat Trout and one of the nation’s premier wild native trout fisheries. This population is unique across its range in that it maintains all life history strategies including mainstem spawners and residents, tributary residents, and tributary spawning individuals with extensive fluvial migrations. The Idaho Department of Fish and Game (IDFG) has monitored this population for years (Figure 1; P. Kennedy and B. High, personal communication; Oldemeyer and Van Kirk 2018; McCormick and High 2020) and conducted numerous management actions to reverse the long-term decline of this population following hydrologic alteration and Rainbow Trout invasion (Figure 1; P. Kennedy and B. High, IDFG, personal communication).

The low carryover in the upper Snake River after the 2021 water year combined with a another year of low water supply in 2022 threatens native Yellowstone Cutthroat Trout by increasing the probability of a high magnitude sediment mobilization event at Palisades Reservoir and consequent deposition in Yellowstone Cutthroat Trout habitats in the South Fork Snake River. As reservoir storage declines to zero, the inflowing water mobilizes fine sediments that have accumulated on the reservoir bottom and export those sediments to lotic habitats below the dam. Controlled reservoir flushing is an increasingly studied technique in some systems to manage sediment accumulation (Espa et al. 2019); however, such releases are intensely monitored and target high flow periods or use a nearby reservoir dilution release to minimize deposition in nearby stream reaches. In the present case of the South Fork Snake River, sediment mobilized as water deliveries decline in late summer and early fall would likely be deposited in both primary and margin stream channel habitats below Palisades Dam with no ability to mitigate in the near term.

High rates of sedimentation at low flows can alter geomorphic characteristics and functions of river ecosystems by reducing pool depth and causing fine sediment infiltration into existing gravels (e.g., Evans and Wilcox 2014) with consequences for biological functions. High sedimentation can reduce basal ecosystem productivity and organic matter processing (e.g., Macarelli et al. 2015), alter macroinvertebrate communities by decreasing abundance, species richness and evenness (e.g., Relyea et al 2012; Quadroni et al. 2016), and impact the availability of juvenile fish habitat (Griffith and Smith 1993; reviewed by Cunjak 1996). Griffith and Smith (1993) found that juvenile cutthroat trout density in the South Fork Snake River is dramatically lower in habitats with embedded substrate. These processes have long-term impacts on fish population carrying capacity by reducing suitable habitat and prey availability for resident trout.

Sedimentation events are difficult to reverse and are damaging to aquatic health and fisheries (Gamblin et al. 1993; Sepulveda et al. 2015). For example, the emptying of Island Park Reservoir during the 1992 drought resulted in 90,000 tons of sediment being released from Island Park Reservoir and deposited in the Henry’s Fork (i.e., North Fork of the Snake River) through the well renowned river reaches of Box Canyon, Last Chance, and the Harriman State Park. Initial efforts to remove sediments largely failed (Gamblin et al. 1993) and sediment from that event is still present in some areas. Another catastrophic sediment release in Idaho occurred on the Lower Payette River in 2013 when the Bureau of Reclamation drafted Black Canyon Reservoir to 2440’ to study the ability to increase hydropower production, which had severe impacts to habitats and fish populations both in the reservoir and downstream (Kozfkay and Ward 2013).

The Oldemeyer (2022) analysis suggests that sediment mobilization in 2021 began at approximately 8% active storage capacity (Figure 4) or a forebay elevation of approximately 5513 feet. The bottom of active storage is at approximately 5498 feet and the top of dead storage is at 5452.4 feet.

The five lowest autumn period forebay elevations at Palisades Reservoir since the dam was completed in 1957 fell between 5499’ – 5504 feet in years 1990, 2007, 1994, 1977, and 1960. These five years fall near the bottom of active storage at 5498 feet. Forebay elevation will be approximately 5467.5 (15 feet above dead storage; arrived at by linear interpolation) if all active storage in the entire upper Snake system is delivered and 53.3 kaf of Powerhead water remains in Palisades Reservoir. If Powerhead water is released for salmon flow augmentation, the Palisades forebay elevation could approach 5452 feet (i.e., dead storage). We do not know at what forebay elevation between 5452 and 5498 feet a catastrophic sedimentation event may occur.

Total system carryover above Milner Dam following water year 2022 may reach as low as 200- 400 kaf, which underscores the importance of maintaining the remaining Palisades Powerhead water in the storage system above Milner Dam. Beyond sedimentation effects, low carryover in Palisades and across the system will continue to impact fish recruitment in the South Fork Snake River winter 2022-2023 as winter discharge continues to be at or below the 900 cfs minimum advised by IDFG (Figure 5; Oldemeyer and Van Kirk 2018; Oldemeyer et al. 2017) regardless of sedimentation. Additionally, Palisades Powerhead water is the absolute last-to-fill account in the storage system and its release may extend the threat of serious impacts for years into the future under prolonged drought.

Keeping the remaining 53.3 kaf of Palisades Powerhead water stored in the upper Snake River system provides Idaho Department of Fish and Game more flexibility to work with water users to prevent or, at least, minimize the impacts of extreme low water levels in Palisades Reservoir to Yellowstone Cutthroat Trout habitat in the South Fork Snake River and optimize conditions in other areas of the upper Snake River in 2022 in a situation where system storage is low, but not zero.

Potential impacts of implementing the requested operation on ESA-listed anadromous fishes

We acknowledge that keeping remaining Palisades Powerhead water in the storage system of the Snake River above Milner in 2022 will reduce flows in the lower Snake River to some extent with potential impacts on juvenile anadromous salmonid travel time. It is difficult to predict the exact decrease in discharge in the lower Snake River at any given time caused by keeping Palisades Powerhead in the storage system because of the re-regulation of federal salmon flow augmentation water by the Hells Canyon Complex (HCC). If we assume that the volume of physical water delivered to the HCC in the spring is incorporated into the refill curve of Brownlee Reservoir from the start of delivery to the completion of Brownlee Reservoir refill, then mean daily flow in the lower Snake River would be approximately 500-600 cfs higher than if the 53.3 kaf of remaining Palisades Powerhead was kept above Milner Dam. The impact of our request to fish travel time migrating during this period is real, but probably not measurable and difficult to reasonably estimate given that this volume of water translates to probably < 1% of total discharge at Lower Granite Dam for the remainder of the juvenile migration period in 2022.

This request will also decrease water available to guarantee a minimum discharge for the hatchery fall Chinook acclimation ponds at Pittsburg Landing on the Snake River below Hells Canyon Dam just prior to release given the current pump capability. Pumps at the facility require river discharges of 8000-8500cfs to adequately function. In 2021, the Bureau of Reclamation delivered a significant portion of federal flow augmentation water (~200 kaf ) to guarantee minimum flows sufficient to operate the facility until subyearling releases at the end of May. In 2022, remaining Palisades Powerhead water would be the only volume available to deliver during this period and is likely insufficient to support the facility by itself (Table 1). IDFG will work with other Snake Basin fishery co-managers to adapt to the low water situations whether or not Palisades Powerhead water is delivered or remains in the storage system above Milner Dam. Recent weather patterns have maintained inflow to Brownlee Reservoir that may be sufficient to achieve the minimum flow for this hatchery program.

Conclusion:

In 2022, we contend the benefits of ~53.3 kaf of Palisades Powerhead water have greater potential benefit to Yellowstone Cutthroat Trout and ecosystems in the upper Snake River if stored in the storage system above Milner Dam than the potential benefit to anadromous fishes below the Hells Canyon Complex if the volume were delivered for salmon flow augmentation.
2. Requester(s) Idaho Department of Fish and Game. This SOR is also supported by: Idaho Governor’s Office of Species Conservation; Henry’s Fork Foundation; Committee of Nine – Water District 01
3. TMT Recommendation May 18, 2022, TMT Meeting.

IDFG, presented on SOR #2022-4 (posted to the TMT website), which requests that the remaining 53.3 kaf of Palisades Powerhead water in Reclamation’s reservoirs in the upper Snake River above Milner Dam, be kept in the storage system in 2022. It is IDFG’s technical opinion that the risks to wild resident trout from releasing the remaining Palisades Powerhead water outweighs the benefits to anadromous fish, given the water supply and water conditions in the upper Snake River.

Reclamation’s upper Snake field office, reported on expected reservoir elevations moving into summer and fall. He highlighted projections for pool levels throughout the basin, including 100 kaf remaining at Henry’s Fork at the end of the year and 75 kaf expected at Jackson Lake (mainstem of the Snake basin upstream of Palisades). The Reclamation emphasized that powerhead use and irrigation will influence where Palisades ends up at the end of the year, and estimated that Palisades will be in the lower range regardless of whether the powerhead water is used or kept in the system. The Reclamation also noted that due to the dry conditions, Reclamation expects that there will be sediment concerns at Palisades and throughout the watershed. Although there is limited flexibility due to the dry year, it is anticipated that the remaining 75 kaf in Jackson that could potentially help address sediment concerns from Palisades. In response to inquiry from IDFG, The Reclamation shared that Reclamation meets with Wyoming Fish and Game regularly and will address the sediment concerns and use of Jackson water.

TMT Members were polled on the SOR, with some providing additional rationale for their responses:

o NOAA = Object without elevation. NOAA considers the flow augmentation as described in the proposed action and considered in the BiOp to be meaningful for both habitat quality and ecosystem process. They also understand the increased flow will lead to measurable improvements in travel time, which data generally show improve survival and increase adult returns. NOAA believes the flow augmentation remains important and doesn’t agree with some minimal language in the SOR. Current information shows that the magnitude of the reduction in the reservoir elevation and the associated sedimentation in the hypothesized impact to cutthroat trout is not certain, and will be largely impacted with reservoir management like the Jackson operation and irrigation. NOAA is also sympathetic to the IDFG concern for their resource and think it’s important. NOAA looks forward to working with IDFG, Reclamation and the surrounding region to find good solutions to help preserve the resources while protecting ESA listed salmonids.

o OR = Object (with/without elevation not stated). Oregon’s concerns align with NOAA’s statement. They emphasized their concern that this is yet another situation where different uses of the resources are pitted against each other, resulting with biological components losing coverage. Oregon is also concerned about sediment management actions and wondered if the sediment could have been managed differently and to help avoid the current situation.

o WA = Abstain. Washington abstained as they had not yet fully vetted the SOR internally. They appreciate the difficulty in taking a course of action, and recognize valid concern on both sides. The potential sedimentation is a significant impact, and Washington supports further discussion and the elevation to RIOG.

o Confederated Tribes of the Colville Reservation = Abstain. Colville Tribes also have not had an opportunity to fully vet the SOR internally. They abstained from polling given the volume of water in question indicated that this is likely more of a Snake River Basin issue rather than a Columbia River mainstem issue.

o Confederated Tribes of the Umatilla = Object without elevation. Umatilla Tribes acknowledged and understood that Idaho had worked on mitigation but it had failed. They felt that the SOR should have included what mitigation had been considered, as mitigation would be critical to get Salmon mangers support of this SOR. They invited other parties to come up with possible offsets that might be easier for the AAs and Salmon Managers to support the SOR. They sympathize with Idaho and recognize this is a challenging issue. It is difficult to balance all needs and to not to pit one species against another.

o Reclamation = Object without elevation. Reclamation hears Idaho’s concerns and has been working with this issue for the past couple months; they will continue to work with irrigators and local agencies to address sedimentation issues as they arise throughout the summer. The BiOp dictates that Reclamation’s position is that they need to release the water as stated in the 2008 BiOP.

o Corps = Abstain. The Corps abstained because they need more time to coordinate with Accord partners.

o USFWS = Abstain. USFWS abstained not because they are uninterested in Idaho’s concerns; they are struggling to determine the likelihood of a sedimentation event actually occurring and its impact, and their primary charge is Bull Trout. They agree that flow augmentation water is important and the region has responsibilities to native trout species. The issue warrants more discussion and careful monitoring; overall USFWS doesn’t have enough information to make a fully informed decision.

o IDFG = Support. The State of Idaho supports the flow augmentation program and has kept their commitment to provide water to the border for 15 years. The BiOp recognized that the full flow augmentation would not always be available and after two years of drought, this is a very difficult water year for managing resident fish. They believe the risks to resident fish caused by releasing water vastly outweighs the benefits of this volume of water to anadromous fish in 2022.

o MT = Abstain. Montana empathizes with the challenge Idaho faces, recognizing that often with high temperatures and low water, resident fish are more sensitive than the downstream anadromous fish. They abstained due to the amount of uncertainty around the water supply and think it’s a good idea to keep this SOR on the radar for later. Montana is encouraged that Reclamation acknowledged the sediment problem, and think working together is important for the common good of upstream and downstream species; it’s also good to consider the Columbia basin as a whole. They still have uncertainties on if other water users understand the sediment issues, and if there are other ways to conserve water or intercept sediment.

o Nez Perce Tribe = Object with elevation. The Nez Perce Tribe is sympathetic to potential impacts to resident fish, however, their bottom line is that the efforts to secure water for anadromous fish were born out of a congressionally approved settlement that was followed by a biological assessment in the BiOp, and those commitments for water downstream are absolutely essential to maintain.

o Bonneville = Abstain. BPA supports Reclamation as manager of the upper Snake system as they work to meet requirements in the BiOp, and to meet the needs of the State of Idaho as best as they can.

o Kootenai Tribe of Idaho, Spokane Tribe of Indians, and the Confederated Tribes of Warm Springs were not present to register a polling response.

Action Agency Decision

Reclamation plans to release the Palisades Powerhead water. The water was previously slated for release starting on May 23, however, given the colder weather conditions and the desire to elevate the issue to RIOG, Reclamation can wait to release the water until May 30 at the latest. Joel noted that the BiOp asks Reclamation to release the water early, particularly in dry years, but in this case, the issue will be elevated and discussed further so the delay is appropriate. It was recognized that RIOG may offer a different recommended path forward.

TMT Members were polled on Reclamation’s decision to not implement the SOR, and to delay the water release no later than May 30.

o NOAA = Support. No additional comments.

o OR = Abstain. No additional comments.

o WA = Abstain. No additional comments.

o Confederated Tribes of the Colville Reservation = Abstain. No additional comments.

o Confederated Tribes of the Umatilla = Support. No additional comments.

o Reclamation = Support. No additional comments.

o Corps = Abstain. No additional comments.

o USFWS = Abstain. No additional comments.

o IDFG = Object with elevation. Idaho will elevate the issue to the policy level. They noted that TMT is charged to look at the technical merits of the request and believes that much of the technical information has been glossed over, including the risk/benefit analysis. Idaho believes that TMT partners may be objecting to the request on principal. Idaho remains very concerned for fisheries in the Upper Snake system.

o MT = Support. No additional comments.

o Nez Perce Tribe = Support. No additional comments.

o Bonneville = Abstain. Once again, abstaining but supporting Reclamation as they are the decision makers and technical experts on managing the BiOp, while doing their best to meet Idaho’s needs.

o Kootenai Tribe of Idaho, Spokane Tribe of Indians, and the Confederated Tribes of Warm Springs were not present to register a polling response.

Action: IDFG will bring the SOR to RIOG, as quickly as possible before May 30, at which point Reclamation will begin flow augmentation unless RIOG conversations result in a new path forward.

ID asked that the Palisades water not be released prior to the RIOG discussion. The Facilitator, encouraged TMT Members to brief their RIOG representatives on the technical aspects of the SOR as soon as possible.
4. AA Decision May 18, 2022, TMT Meeting.

Reclamation plans to release the Palisades Powerhead water. The water was previously slated for release starting on May 23, however, given the colder weather conditions and the desire to elevate the issue to RIOG, Reclamation can wait to release the water until May 30 at the latest. Joel noted that the BiOp asks Reclamation to release the water early, particularly in dry years, but in this case, the issue will be elevated and discussed further so the delay is appropriate. It was recognized that RIOG may offer a different recommended path forward.
5. IT Recommendation  
6. AA decision (post IT)  
7. Actual Implemented Operation June 1, 2022, TMT Meeting.

For flow augmentation, Reclamation noted that yesterday, Reclamation began releasing the powerhead from Palisades out of Milner at 1,000 cfs, and will increase to 2,000 cfs tomorrow; with the intent to finish by mid- June. The Boise and Payette are still filling, and there may be unexpected bonus water on the horizon; new prospects should be confirmed next week.

June 15, 2022, TMT Meeting.

With the recent changes, flow augmentation prospects are unclear, and Reclamation expects between 320- 380 kaf total throughout the whole upper Snake. The release of Palisades Powerhead water finished this morning, and the operation has ceased. Reclamation expects 40 kaf out of the Boise. Additional rentals are not expected, although there may be some from Anderson Powerhead. New accounting should come out today, and Reclamation is still working on volume totals.

Regarding reservoirs: The Payette is in active flood operations (controlling for refill); the lower system of Boise River system has filled; Anderson may miss refill. The upper Snake is doing much better, although Reclamation was not sure on summer projections. There is good storage in upper system (Palisades, Jackson). American Falls is drafting now for irrigation (typical operation pattern). Joel noted that Reclamation will have a better sense of projections in another 1 or 2 weeks as the weather systems move through.

June 29, 2022, TMT Meeting.

Upper Snake Flow Augmentation: The 53,000 acre-feet of Palisades Powerhead have been released. Both the Payette and Boise systems are releasing their flow augmentation volumes. Total flow augmentation should come in at 365 kaf this season. This is an 85 kcfs increase from the last update Reclamation gave. Most of this is from the Payette system, which is estimated to provide 179 kaf. There will be about 83 kaf from rentals. If rentals do come in at that amount, it will be much larger than normal – in fact, it may be a record, noted Reclamation. On the Boise, there should be about 56 kaf of flow augmentation water, with 14 kaf coming out of Anderson Powerhead, which had not previously been on the flow augmentation list for this year due to drought conditions.
8. If different from AA decision, why?