A brief look at progress and accomplishments of implementing GGSA’s 27 project Salmon Rebuilding Plan
Baby salmon migrate at night but will stop in their tracks when they swim into lit spots. Predator fish have figured this out and ambush them from the shadows the minute the baby salmon swim into the lights. Answer: dim the lights shining on the water!
GGSA’s Salmon Rebuilding Plan includes a project calling for brightly lit spots on Central Valley salmon rivers be eliminated or dimmed, at least during periods of juvenile salmon migration. The City of Redding now seasonally dims the lights on the Sundial Bridge (pictured above) but much work remains.
The USFWS and Bureau of Reclamation’s Central Valley Project Improvement Act Restoration Fund has allocated $183,000 for two years to identify the worst night lit areas on the Sacramento River as a first step towards bringing them under control. In addition to identify the brightest areas, part of the funding may be used to establish a lighting threshold or standard safe to salmon. Part of it might be used to develop a voluntary program to educate light owners and get them to turn down the lights.
Baby salmon like shallow water habitat with natural vegetation where they can find food and hide from predators. Instead what they’ve got in today’s Delta is mostly deep water channels lined with giant construction boulders. Much of the once good rearing habitat in the Delta for baby salmon has been destroyed by human development. The good news; some of it can be restored and GGSA calls for this. If it is, survival of baby salmon will improve.
The USFWS and Bureau of Reclamation’s Central Valley Project Improvement Act Restoration Fund has allocated $1.5 million over three years to address this GGSA Salmon Rebuilding Plan project.
C.1 Natural and artificial velocity and predator refuge structures
Baby salmon in the upper Sacramento River lack good places to safely tuck away from predator fish and out of high velocity currents in the middle of the river. Gone are the natural side channels that were once everywhere. This project proposes anchoring massive tree root structures at key points in the river. The baby fish find safety in the root maze where predators can’t get at them. At the same time they catch a break from heaving mid-stream currents in the back eddies created by the trunks.
The USFWS and Bureau of Reclamation’s Central Valley Project Improvement Act Restoration Fund has allocated $381,600 over 5 years to work on this problem. River Gardens Farm, an irrigation district in the Sacramento Valley, agreed to help underwrite the project and the first phase was done in 2017. By August of 2017 solid evidence emerged showing it was working. We owe River Garden Farms a big thank you for making this project happen.
GGSA has proposed fixing some of the worst Delta predator hot spots which are death traps for baby salmon. Levee breaches where subsequent tidal see-sawing over years has cut deep holes allows predator fish to hold in and ambush baby salmon, in high numbers. GGSA’s proposal is to modify the bottom by feathering the edges of the holes or possibly filling them to take away the advantage predator fish currently have.
The USFWS and Bureau of Reclamation’s Central Valley Project Improvement Act Restoration Fund has allocated $386,900 over two years to work on this problem.
Restore Rearing and Spawning Side Channels in the Upper Sacramento and Feather Rivers
A major challenge for Central Valley baby salmon is the loss of side channels and floodplain where food is plentiful and predators can be avoided. Another problem is lack of spawning
Gravel due to blockage of natural gravel replacement caused by dams. GGSA has addressed these problems by calling for restoration of rearing and spawning habitat. The US Bureau of Reclamation has allocated several million dollars to start the work by restoring 13 side channels and injecting gravel at various sites in the upper Sacramento River.
GGSA succeeded in getting the state of California Dept. of Fish and Wildlife to publicly support the 13 side channel and gravel restoration projects. This support broke through a permitting road block and allowed work to get underway in early 2016.
River temperatures over 56 degrees lead to loss of incubating salmon eggs buried in river gravels which is why GGSA has called for this temperature thresh hold.
GGSA elevated the case that temperatures for winter run salmon were routinely violated by Bureau of Reclamation operations in 2014 and 2015, resulting in spawning failure. This helped provide NMFS fish managers with a stronger political hand to successfully force reforms in 2016 resulting in greater winter run production and survival.
B.11 Smooth Keswick Releases from Sept. – Nov to Eliminate Stranding Redds (salmon nests)
In most years the federal Bureau of Reclamation drastically reduces water releases from Shasta Dam in the fall, often just as fall run salmon are burying their fertilized eggs in shallow water river gravels. The sudden drop in releases often shrinks the river and removes the flows needed to keep the eggs underwater. Losses as high as 40 percent has resulted in some years. GGSA has a project calling for an end to this practice.
Dewatering of fall run redds has been reduced because of GGSA public focus and pressure on water managers. Before GGSA’s attention to this, redd dewatering during the fall was fairly routine with little or no political cost to the offenders. The outcome will be higher success for spawning native salmon.
The arrows point to salmon nests constructed in the restored Painters Riffle in 2015
In 1986, a California Department of Fish and Game biologist, Dick Painter, designed and constructed a side channel salmon spawning riffle area in the Upper Sacramento River downstream of the Highway 44 bridge in Redding.
Painter’s Riffle was successful for a number of years in producing 100 to 200 additional redds, or salmon nests. Gravel placed at the Highway 299 Bridge during construction activities washed downstream in 2011 and filled in much of this spawning area.
GGSA first flagged the site as one in need of restoration. The Glen Colusa Irrigation District offered its heavy equipment and operators and worked together with GGSA to wrest the needed permits to get the job done in December 2014. Salmon started spawning in the channel starting the next spring.
Painters Riffle prior to restoration
Map of Painters Riffle prior to restoration
Heavy equipment and operators from the Glen Colusa Irrigation District removed the gravel to restore the spawning channel for salmon
A.5 Egg Injection
Manually injecting fertilized salmon eggs into river gravels is a method that’s been used to restock areas with salmon. It can be a particularly useful tool in the case of drought where elevated river temperatures kill eggs deposited during hot periods in the fall. Fertilized eggs can be held in hatcheries until later in the fall when river temperatures cool enough to support incubation and hatch.
GGSA’s Salmon Rebuilding Plan calls for experimenting with egg injection, never before done in California, to gain knowledge and experience which could be used in the next drought. GGSA convinced the California Dept of Fish and Wildlife to work together on a pilot project testing the efficacy of this approach. The first year, 2015, yielded mixed results but plenty of lessons learned. A second year, during the winter of 2016/17, was aborted after a very wet winter with high flows made the rivers unsafe to do a pilot project in.
A.4 Eliminate Adult Attraction Into the Colusa Basin Drain
The Colusa Drain drains the west side of the Sacramento valley, emptying into the Sacramento River at Knights Landing and sometimes into the Yolo Bypass. When adult salmon swim into it, there is no outlet and they are trapped and perish. In recent years hundreds of ESA-protected winter run salmon got trapped in the drain.
GGSA called for a fix in its Salmon Rebuilding Plan and major progress, led by Reclamation District 108, has been accomplished. A new facility replaced the old Knights Landing Outfall Gates where the drain and Sacramento River meet. In the Yolo Bypass, a new blocking structure and fish trap were built in 2016 to stop all adult salmon movement in the drain through this route. This project is now complete.
Wallace Weir in Yolo Bypass was beefed up in 2016 to block access to adult salmon into the Colusa Basin Drain.
The Knights Landing Outfall Gates have been rebuilt to keep adult salmon out of the Colusa Basin Drain.