American River Water Forum 2.0 – The Future for American River Salmon and Steelhead

Conditions in the lower American River have been bad all year, and are getting worse.1 Folsom Reservoir storage never recovered this spring and is critically low this summer (Figure 1). Releases from reservoir to the river have been low (Figure 2), resulting in excessively warm river water temperatures (Figure 3).

In a recent post on the Water Forum’s blog, Jessica Law, the new executive director of the American River Water Forum, described current conditions for the lower American River:

I won’t sugarcoat it. Conditions in the river will be bad. However, the Water Forum and our partners are working hard to ensure conditions are as good as they can possibly be, and to minimize harm to fish and habitat. As you may have seen on the news, we began this year with a near-normal snowpack. In most years, the snowpack melts and feeds our lakes and rivers. This year, the snowpack disappeared in the span of several weeks, soaking into the dry soil or evaporating—perhaps foreshadowing what may turn out to be the case study for climate change impacts on our water supplies and environment.

In a recent interview with Matt Weiser posted in Maven’s Notebook, Ms. Law further elaborated about the update of the original Water Forum Agreement from the year 2000.

“The biggest thing we’ve done is develop and implement a Modified Flow Management Standard with Reclamation that governs water movement in the Lower American River and optimizes conditions for fish. So that’s huge. …

But at some point, nature is moving faster than we can keep up. This year, with another extreme drought in play, is a great example of that. We had better water storage in all reservoirs coming out of a dry year than we ever had. This was very intentional by Reclamation and the Department of Water Resources. Still, we’re in a really bad situation this year.

Yet there is more to the story than natural conditions. Notwithstanding the Modified Flow Management Standard, fisheries in the lower American River have been struggling for many years.2

Reservoir inflows are low and water temperatures are high in summer of drier years (Figures 3 and 4), because Reclamation fails to conserve storage and the reservoir’s cold-water pool in most years. In the drier years, high June releases to meet Delta requirements and/or export demands lead to lower summer storage and high July water temperatures (Figures 1-3). Low reservoir storage levels lead to lack of access to the cold-water pool. Peaking power releases in afternoon-evening period draw warmer water from the surface of the reservoir (Figure 5).

A part of the solution to the problem is to have strict rules on end-of-year storage (Figure 7):

  1. 500,000 AF in high-storage years
  2. 350,000 AF in intermediate-storage years
  3. 250,000 AF in low-storage years

It is no longer enough to set end-of-September storage targets. Climate change means in part that more autumn months are very dry. Exports in the fall (and a transfer season now extended through November) pull down CVP storage or at least slow reservoir refill. Storage at the end of November or end of December needs to an explicit part of the carryover calculus. Figure 7 shows end-of-November as the requirement.

Complying with these rules (criteria) would occur through strict management of summer-fall storage releases. It would begin with the higher requirements for high-storage years, when there is water to manage. This would help prevent excessive drawdown from cascading into catastrophic conditions in one year.

Conserving storage in spring of drier years is also important in maximizing water storage for the beginning of summer. Use of Folsom Reservoir to meet short-term Delta water quality demands in winter and spring of drier years like 2021 (Figure 6) exacerbates summer storage and water temperature problems. This also wreaks havoc on the lower American River’s steelhead spawning habitat and salmon and steelhead rearing habitat.3

What is running away from managers of the lower American River is not only climate conditions. It is also the relentless pressure on other Central Valley Project (CVP) and State Water Project (SWP) reservoirs that forces Folsom Reservoir to shoulder more of the burden than it can bear. The explicit goal of “maximizing deliveries” in purpose-and-need statements of the 2019 Biological Opinions for the operation of the CVP and SWP are just one aspect of this pressure.

The over-delivery of irrigation water from Shasta Reservoir to Sacramento River Settlement Contractors in the spring and summer of 2021 made much less water from Shasta available to meet Delta water quality needs. Hence, the sudden demands on Folsom. There is a direct line between deliveries along the Sacramento and the amount of water in storage at Folsom Reservoir. These related problems must be solved to allow implementation of Folsom storage levels to be truly protective.

In summary, Water Forum 2.0 should focus on conserving Folsom Reservoir’s cold-water pool, providing access to the cold-water pool, minimizing the adverse effects of peaking power on river water temperature, and minimizing use of Folsom storage for short-term Delta water needs. While much of the focus must be on drier years, especially years like 2015 and 2021, overuse in high-storage type years can also lead to future problems.

For more detail on the salmonids and their habitat conditions in the lower American River see https://www.calfish.org/Portals/2/Programs/CentralValley/LAR_RST/docs/2020%20LAR%20RST%20Emigration%20Monitoring.pdf .

Figure 1. Folsom Reservoir storage patterns in four drier years: 2001, 2008, 2015, and 2021.

Figure 2. Folsom/Nimbus Reservoir releases to the American River at Fair Oaks in June-July of four drier years: 2001, 2008, 2015, and 2021.

Figure 3. Water temperature in the lower American River at William Pond gage in June-July of four drier years: 2001, 2008, 2015, and 2021. Red line is the upper limit of water temperature considered safe for salmonids.

Figure 4. Dry years 2001, 2015, and 2021 June-July inflow to Folsom Reservoir. Note 2015 and 2021 were very similar.

Figure 5. 48 hours of flow (cfs/100) and water temperature (oF) from Folsom Dam beginning 7/26/21 at 08:00 hours.

Figure 6. Folsom Reservoir daily-average storage releases (cfs) October 2020 to July 2021. Note each rectangle represents approximately 15,000 acre-ft of storage water. The three peaks in spring represent approximately 100,000 acre-ft of the end-of-June storage in Figure 1, or roughly about half the difference between 2015 and 2021 beginning-of-the-summer storage. Higher releases at the end of 2020 also contributed to the difference, along with low precipitation and snowmelt in 2021.

Figure 7. Folsom Reservoir daily-average storage (acre-feet) 2000-2021. Recommended minimum storage criteria are shown by circles: blue for high-storage years; light blue for intermediate-storage years; yellow for low-storage years. Red arrows are years that grossly exceeded such criteria.

What is it about the Scott River and its Coho Salmon?

A recent article in Science Magazine provides a possible clue as to why the Scott River, a California tributary to the Klamath River, still produces a relatively large amount of coho salmon. A chemical released onto roads as tires wear has been found to kill young coho.1 Watersheds like the Scott River are pristine, sourced directly from springs and snowmelt, with low highway interaction. The Scott contrasts with its neighbor the Shasta river, which runs very close to Interstate Highway 5, and which produces few coho salmon.

Absence of pollution from tire debris may also be part of the reason why Butte Creek is able to produce so many spring-run salmon. On the other side of the coin, the prevalence of roads may help explain why coho salmon have been extirpated from many of the highly urbanized Puget Sound watersheds in Washington State and British Columbia.

The recent study regarding pollution from tires emphasizes the need to protect pristine watersheds like the Scott River, as well as the need to restore those like the Shasta River. There is likely to be more public discussion of this subject in the coming months and years, hopefully as the tire industry seeks alternatives to its problem chemical

  1. As described in Science Magazine, the chemical is: “a highly toxic quinone transformation product of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD), a globally ubiquitous tire rubber antioxidant.”

Are Striped Bass Next to Go? 2021 Update

The prognosis for Bay-Delta and California striped bass could not be much worse. Numbers of stripers salvaged at the south Delta pumping plants in 2021 are down to or below 2014-2015 levels.1 Like many other species that spend all or part of their lives in the Delta, striped bass are on a downward spiral. Good water years are not providing enough population rebound to offset devastating lack of recruitment in dry year sequences.

In my report on the status of striped bass in 2016, stripers had suffered terribly in four years of drought (2012-2015). By 2019, the prognosis was still not good after a sequence of wetter water years (2016-2019) that were below normal, wet, below normal and wet.

Now, the summer-to-fall recruitment relationship (Figure 1), with its strong relationship between the summer index and fall recruitment, shows that dry year 2020 recruitment was as low as during the critically dry drought years 2014 and 2015. In the critically dry drought year 2021, late spring net catches are at historic lows.2 If the summer-to-fall recruitment relationship holds in 2021, striped bass are circling the drain as the next fish species to be lost in the collapsing Bay-Delta ecosystem.

Figure 1. Striped bass Fall Midwater Trawl Survey Index (log10[index+1]) versus prior Summer Townet Index (log10). Select years labeled, with color of number showing year type: blue=wet, green=normal, and red=critically dry.

Butte Creek Spring-Run Chinook Salmon in Peril

Butte Creek DeSabla – Centerville Project options1 could help save the salmon

Butte Creek’s spring-run salmon are dying in droves (over 12,000 carcasses of un-spawned adults counted so far in summer 2021) in their over-summering reach upstream of Centerville. A huge run of the most important core element of the California Central Valley Spring-Run ESU is being wiped out by low flows and high water temperatures.

This year’s spring-summer salmon migration and holding water temperatures have been about 5ºC higher than normal (Figure 1). Average daily water temperatures where adult salmon have been holding were over 20ºC for a solid month from the third week in June through the third week in July. Though the immediate cause of this year’s die-off is not known, these temperatures can lead to disease and even hypoxia in overcrowded conditions. Streamflows have also been well below average in 2021 (Figure 2). This is a consequence of reduced snowmelt and of reduced water available from PG&E’s Hendricks diversion from the West Branch of the Feather River, part of PG&E’s DeSabla-Centerville Hydroelectric Project.

After decades of successful recovery progress, the recent trend for spring-run salmon in Butte Creek is downward (Figure 3). The huge loss this summer of what was to be a recovery run will make the trend worse.

PG&E has operated the DeSabla – Centerville Project (Figure 4) for a century, but decided in 2017 to withdraw its application for a new license to continue operating the project. PG&E is in the process of trying to sell the project, but after four and a half years, the sale, and the suitability of the prospective buyer, are not certain. Meanwhile, needed improvements to the project have been on hold. In particular, infrastructure to reduce heating of water in a small project reservoir just uphill from DeSabla Powerhouse on Butte Creek could have helped reduce water temperatures in Butte Creek this year.

Without the 40-100 cfs of cool summer water available from the West Branch of the Feather River via the DeSabla project, water temperature and flow conditions would be even worse, and sustaining spring run in Butte Creek might not be possible. Therefore, some stakeholders have suggested that the State of California, specifically the Department of Water Resources, should consider taking over the DeSabla project to secure cool water from the West Branch Feather River for the immediate future.

An additional phase of actions on Butte Creek could entail removing the Lower Centerville Diversion Dam, a low-head dam on Butte Creek just downstream from the DeSabla powerhouse (Figure 4). Removal of the dam and diversion could be a first step in allowing access to many miles of upstream spawning and rearing habitat on Butte Creek presently blocked by the dam. It is likely that several natural barriers might also need to be modified.

As climate change strikes California with an accelerating vengeance, options to protect and recover California’s salmon are becoming fewer and more difficult. Salmon are dying in greater numbers and with more frequency on the floor of the Central Valley. Projects and alternatives to move salmon back into higher elevation habitat seemed far-fetched or exorbitant a decade ago. They require a fresh and more expansive look today.

Figure 1. Water temperature recorded April-July 2021, plus recent four-year average.

Figure 2. Streamflow recorded April-July 2021, plus 90-year historic average.

Figure 3. Butte Creek annual spring-run salmon snorkel counts. Data Source: CDFW.

Figure 4. Modified DeSabla Project concepts. Solid red line is continued transfer of West Branch of Feather water via DeSabla powerhouse. Red “X”s denote options to remove diversion dams and power canals.

 

  1. The Central Valley Salmon and Steelhead Recovery Plan (NMFS 2014) includes an action to evaluate a Butte Creek water management option for the PG&E DeSabla-Centerville Hydroelectric Project to determine the flow conditions that optimize coldwater holding habitat and spawning and rearing habitat.

Feather River Salmon Recovery Responsibilities, Commitments, and Recommendations

The State Water Project (SWP) is not protecting salmon in the Feather River.  The Feather River’s once-prolific populations of wild spring-run and fall-run salmon have been replaced by smaller numbers of hatchery fish of inferior genetic composition.

The fact that the replacement of wild fish by hatchery fish plagues all salmon stocks in the Central Valley Evolutionarily Significant Units (ESUs) is no excuse.  The California Department of Water Resources (DWR) has many responsibilities and commitments to protect Feather River salmon under the SWP’s project’s hydropower license, water rights, and other permits, and more generally under the public trust doctrine and the reasonable use doctrine in the state constitution (Article X, Section 2).  The SWP has not met these responsibilities or related commitments since the SWP’s completion in the 1960s.

Neither Feather River nor Central Valley salmon recovery can be achieved without cleaning up the mess in the lower Feather River.  This fact is recognized widely in salmon recovery plans, federal biological opinions, State incidental take permits, and even in part in the Oroville Settlement Agreement for the relicensing of the SWP’s hydroelectric facilities at Oroville.  DWR has made many promises and commitments toward salmon recovery, but has realized very few.  While DWR has spent billions on upgrading project infrastructure, especially after the 2017 spillway failure, it has spent little toward salmon recovery.

So how should DWR focus its salmon recovery process for the Feather River at this point?

Well, most certainly on mandatory provisions in the soon-to-be issued FERC hydropower license and related State Board water quality certification.  Also, on existing or needed conditions in its water right permits that extend beyond the small geographic scope of the FERC license.  The next focus should be on  the “Habitat Expansion Agreement for Central Valley Spring-Run Chinook Salmon and California Central Valley Steelhead” (HEA) that DWR and Pacific Gas and Electric Company (PG&E) agreed to during the Oroville relicensing.1 There are also requirements in the Reasonable and Prudent Measures in the 2016 federal biological opinion for the Oroville relicensing.

The overall focus should be on recommendations in specific salmon recovery plans pertaining to the project.

Below are my recommendations for top priority actions for Feather River salmon recovery from among the sources mentioned above.

Spring-Run and Fall-Run Salmon Introgression

A primary focus and priority should be on minimizing introgression of the spring-run and fall-run salmon populations in the hatchery and natural spawning area of the 8-mile Low Flow Channel (LFC) downstream of Oroville Dam.

For the natural spawning area of the LFC, one option is a segregation weir at the lower end above the Thermalito Afterbay outlet that would provide for selective passage of selected adult spawners into the spawning area.  Similar weir systems are operated in lower Battle Creek and lower Butte Creek.  For example, the weir could provide seasonal passage to accommodate only spring-run spawners that arrive earlier than fall-run.  The fall-run would be forced to spawn downstream of the afterbay outlet in the High Flow Channel (HFC) where habitat conditions, especially water temperatures, would be more suitable later in the year when fall-run salmon are spawning.  The weir could also trap fish to allow direct segregation or egg taking, or trapping-and-hauling of selected adults or offspring produced in the LFC.

The hatchery program should focus on broodstock selection and hatchery operations that produce returning adult spring-run and fall-run salmon of the highest genetic integrity possible.   It should also operate to limit straying of Feather River origin hatchery salmon.  Hatchery operations should also focus on strategies for smolt releases that provide the greatest return while limiting effects on wild salmon.  Otherwise, the Feather River Fish Hatchery Improvement Program (Article A107 of the Oroville Settlement Agreement) should be implemented.  This program sets specific targets for hatchery temperatures, requires development of a hatchery management program (including a Hatchery and Genetics Management Plan), potential installation of a water supply disinfection system, and funding for annual hatchery operations and maintenance.

Lower Feather River Habitat Improvements

There are many potential habitat improvements in the LFC and in the High Flow Channel (HFC, the lower Feather River downstream of the outlet of Thermalito Afterbay).  Habitat improvements could provide significant benefits to adult salmon holding and spawning success, and wild fry survival and smolt production.  One general category is water quality (i.e., water temperature) and streamflow management through improved infrastructure and operations strategies of flow releases to the LFC and HFC.  The second category is improvements to the physical (non-flow) habitat features, including channel configuration (depths, velocities, and substrate composition) in both the LFC and HFC.

Flow and Water Temperature

Adult spring-run salmon migrate in spring to the lower Feather River, then hold in deep pools over the summer to spawn in early fall.  Adequate flows and cool water temperatures are essential elements of (1) spring adult migration habitat in the lower Feather River and (2) over-summering holding habitat.  Without adequate flows for migration and holding, adult salmon are prone to disease and pre-spawn mortality, poor reproductive success, or lower survival of eggs.  Water temperatures should be no higher than 65oF during migration and 60oF during holding to minimize such detrimental effects.  Water temperatures in the HFC (or LFC) should not exceed 65oF in spring (Figure 1).  Water temperatures in the LFC should not exceed 60oF in summer (Figure 2).  The various planning documents outline potential options to reduce water temperatures in the LFC and HFC.  These include measures to sustain Oroville Reservoir’s cold-water pool and reliably release water from it.  They also include measures to keep water in the Afterbay complex cooler prior to release into the HFC.  Still other measures may include limiting release of water from the Afterbay through a variety of modifications to facilities and operations.

Physical Habitat Features

The Biological Opinion and Settlement Agreement for the Oroville relicensing include prescriptions for the restoration and enhancement of lower Feather River salmon habitat, consistent with the NMFS Salmon Recovery Plan:

  1. Design and build infrastructure and stream channel features that will allow for segregation and reproductive isolation between fall-run and spring-run Chinook salmon naturally spawning in the LFC of the Feather River.
  2. Develop a spawning gravel budget and introduction plan, and implement the plan.
  3. Design, construct, and maintain side-channel and off-channel habitats for spawning and rearing salmon and steelhead.
  4. Obtain river riparian and floodplain habitat through easements and/or land acquisition as needed, allowing the river room to grow and move as necessary to provide key transition habitats, and to minimize degradation (such as channel incisions/filling and substrate armoring) of existing high quality habitat features. Provide a balance between the needs of flood conveyance, recreation, and aquatic, riparian and floodplain habitat in and near an urban environment.
  5. Design, build, and maintain channel features that provide optimum habitat, fish passage, and flood control necessary to minimize scour and erosion. High-flow floodplain channels may be such a feature.
  6. Provide deeper holding habitat and cover for adult over-summering spring-run salmon in the channel habitat features described above. Such habitat is often larger pools with a large bubble curtain at the head, underwater rocky ledges, and shade cover throughout the day. Adult spring-run Chinook salmon may also seek cover in smaller “pocket” water behind large rocks in fast water runs.

Benefits to Other Species

Efforts to improve salmon habitat in the lower Feather River will benefit other important native fish.

The lower Feather River is home to other significant fisheries resources including the following:

  • Spawning anadromous steelhead – spawning is concentrated in Low Flow Channel below the Fish Barrier Dam in winter and spring.
  • Steelhead eggs in gravel redds are concentrated in Low Flow Channel below the Fish Barrier Dam in winter and spring.
  • Steelhead yearling smolts rearing occurs in the Low Flow Channel and the High Flow Channel in winter and spring.
  • Steelhead fry rearing occurs in the Low Flow Channel and the High Flow Channel in winter and spring.
  • Spawning of green and white sturgeon occurs in spring in the High Flow Channel.
  • Sturgeon eggs are found in rock crevices of the river bottom in the High Flow Channel in spring.
  • The newly hatched larvae and fry of sturgeon occur on the river bottom in the High Flow Channel in spring.
  • Resident trout and non-salmonid fish occur year-round throughout the lower Feather River.

Habitat Expansion Agreement – Final Habitat Expansion Plan

The Oroville Project Habitat Expansion Agreement (HEA) requires creation of habitat suitable to increase populations of Central Valley spring-run Chinook salmon by a minimum of 2000 adults.  The Habitat Expansion Plan proposed by DWR and Pacific Gas and Electric Company (PG&E) focuses on physical habitat improvements to the Lower Yuba River to benefit spring-run Chinook salmon.   According to DWR and PG&E, this would develop a viable, self-sustaining population of spring-run Chinook salmon below Englebright Dam.

In my opinion, this is a big mistake.  The lower Yuba River below Englebright Dam has many of the same problems as the lower Feather.  Its spawning habitat already has capacity for many more spring-run salmon than are currently utilizing it.

A much better option is saving the Butte Creek spring-run salmon, the largest core population of the CV Spring Run Salmon ESU.  A first phase of a Butte Creek recovery program would be to secure Butte Creek’s supply of cold Feather River water for the immediate future.  PG&Es decommissioning of the DeSabla-Centerville Hydroelectric Project would potentially eliminate or reduce cold-water inputs from the West Branch of the Feather River to Butte Creek.  The DeSabla Project moves water from the West Branch Feather in canals for release into Butte Creek through the DeSabla Powerhouse.  This additional, relatively cool water provides holding and spawning habitat that presently sustains Butte Creek’s spring-run salmon and supports Butte Creek’s fall-run salmon and steelhead.

A second phase of a Butte Creek recovery program would entail removal of the Lower Centerville Diversion Dam, a low-head dam on Butte Creek just downstream of the DeSabla powerhouse (Figure 3).  Since 2014, this dam has not diverted any water.  Removal of the dam and diversion, and potentially removal or modification of other fish passage improvements at natural barriers if needed, could allow access to many miles of upstream spawning and rearing habitat on Butte Creek.  This would truly expand spring-run habitat in the Central Valley.

Summary and Conclusion

Feather River salmon recovery should proceed through improvements in flow, water quality, and physical habitat, project operations and facilities, and hatchery operations and facilities.  Habitat expansion for spring-run salmon should focus on saving the existing run of spring-run salmon on Butte Creek and expanding their upstream range, not on physical improvements to the lower Yuba River.

Figure 1. Water temperature in the lower Feather River within the HFC in spring 2020 and 2021. Red line is upper water temperature safe limit for migrating salmon.

Figure 2. Water temperature in the lower Feather River within the LFC, 2013 and 2021. Red line is upper water temperature safe limit for pre-spawn, adult holding salmon.

Figure 3. Map of PG&E DeSabla Hydroelectric Project features on Butte Creek and the West Branch of the Feather River.