In the last two summers, Winter Run salmon production was greatly reduced by Reclamation’s operations of the Shasta-Trinity Division of the Central Valley Project. While the drought brought on the problem and the specific damaging project operations, the damage done was in large part unnecessary. Furthermore, not all the blame should go to Reclamation – the State Water Board and resource agencies who condoned the damaging operations also deserve some of the dis-credit.
I wrote on the subject in some detail in November.1 Resource and management agencies who were responsible for the failure of two year classes of Winter Run continue to blame the drought or demands of water contractors on Shasta-Trinity storage (Figure 1). Soon they will prepare a plan for the coming irrigation season. The plan will depend greatly on present and coming late-winter weather and hydrology. Given that Shasta Reservoir likely will fill this spring, the plan will likely revert to operations similar to those of 2011 and 2012, the last two years when the reservoir filled.
State Board’s Thoughts
The State Board has been thinking carefully about what to do this summer for Winter Run salmon. 2
- “With the loss of two out of three cohorts of endangered wild winter-run Chinook salmon (2014 and 2015), it is critical that we develop cold water pool resources in the winter and spring to support temperature management needed later in the year for this third wild winter run Chinook salmon year class.” Comment: irrigation deliveries to Sacramento River Settlement Contractors in April and May of the last two years were a major cause of the loss of the cold-water pool in Shasta. This in turn led to high egg mortality in the upper Sacramento River just below Shasta. While cutting the April and May deliveries would have alleviated the greater part of the problem in both years, it is not all of the problem or solution. Operational changes in the Shasta-Trinity Division could have eliminated many of the problems with little impact to irrigation deliveries, at least in 2015.
- “These data reflect a 97.9% mortality of winter-run Chinook salmon eggs and fry on the upper Sacramento River in 2015.” Comment: Yes, the excessive water temperatures allowed by the State Board by relaxing their water quality standards caused the nearly complete loss of 2015 Winter Run production.
- “Shasta operations: Implementation and Exception Procedures for End of September (EOS) Storage of 1.9 MAF or below – As per RPA Action I.2.2.C, if the EOS storage is at or below 1.9 MAF, then Keswick releases shall be managed to improve storage and maintained at 3,250 cfs unless hydrology improves.” Comment: Hydrology in the Central Valley has greatly improved with El Niño, yet releases were kept at 3250 cfs all winter, to the further detriment of the Winter Run, and were only increased well after Shasta exceeded the reservoir level at which Reclamation is supposed to release water to protect against floods. Young salmon need flow pulses to successfully migrate downstream from spawning and rearing areas.
- “Given the substantial mortality of Sacramento River winter-run Chinook during the egg incubation and emergence periods in BYs 2014 and 2015, there is a need to conservatively manage for protection of the third of three winter-run Chinook cohorts, which will return to spawn upper Sacramento River beginning in summer of 2016. In the coming months, Reclamation and NMFS will be evaluating different actions to balance fishery needs, water supply, and water quality to develop a greater likelihood of protecting juvenile winter-run from BY 2016. As mentioned previously, any proposed action will require the cooperation of senior water rights holders on the Sacramento River and a system-wide operational approach to prioritize cold-water storage and operations at Shasta Lake.” Comment: After the failures in 2014 and 2015, we await the final plan for 2016.
- “Under any hydrologic exceedence scenarios, there is a need to maximize water storage in Lake Shasta to comply with the December 15, 2015 adopted Order and also increase the likelihood of successfully implementing a water temperature management plan to benefit winter run Chinook salmon. The NMFS has prepared some initial concepts to achieve storage and temperature goals (Attachment 4) (Figure 2). In general, the proposed concept involves flow release as low as 2750 and 3250 until late May or initiation of a water temperature management plan.” Comment: The suggested NMFS improvements (“2016 adjustment”) would be a great benefit, particularly the 53°F DAT (daily average temperature) at Clear Creek in Redding (CCR). Obviously, 53°F would be a substantial improvement over last year’s allowed 58°F. The change is reasonably conservative given the present state of the population. The 55°F 7-day average daily maximum option leaves too much room for error, such as a day of lethal temperatures. Given the circumstances, we can only hope that NMFS recommends the more conservative approach, as it will also greatly help downstream habitat conditions at Balls Ferry and Jellys Ferry, which would further benefit Winter Run.
Nearly half way through the water year it is safe to say there is a very reasonable chance there will be adequate water resources to save the Winter Run salmon this year. Shasta storage is sharply rising (Figure 3). The reservoir will likely fill this spring for the first time since 2012. The snow pack is also above average.
Reasonable water temperature criteria for 2016 are:
- Maximum daily average water temperature in Keswick Reservoir release – 53F.
- Maximum daily average water temperature at Red Bluff – 58F.
Both these criteria were achieved in 2011 and 2012 (Figures 4 and 5), the last two years when Shasta Reservoir filled.
For more information on saving the Winter Run Chinook Salmon in the Sacramento River and Delta see the following sources: