With the release of Governor Brown’s plan to build water transferring tunnels under the Sacramento – San Joaquin Delta, the push back against the tunnels or a peripheral canal has been Restore the Delta, don’t destroy it. The fear is that the last piece of The California Water Plan, which has always called for a water conveyance structure around the delta, will remove the need to maintain the levees, thus allowing the delta to fall apart and flood all the islands.
My question to those opposed to the tunnels or canal is, “Restore the delta to which point in time?” Our current Sacramento – San Joaquin Delta is a 20th century artifice solely constructed for agricultural with no thought of the ecology.
Tidal marsh lands
It was California’s gold rush that started development in the delta and subsequent mining operations that virtually killed it. Uninvited European settler Josiah Buckman Green who purchased land on Merritt Island in 1850 is credited with building the first remnants of a levy in 18521. At this time the delta was just a vast expanse of tules and wildlife, including grizzly bears, laced with meandering sloughs and rivers.
Hydraulic mining changes rivers
As the placer gold deposits were exhausted miners turned to more efficient methods such as hydraulic mining. Between the 1850’s and 1884, when most of the hydraulic operations ended in California due to the Sawyer Decision, it is estimated that 1.5 billion cubic yards of earth and rock were washed into the rivers leading to the delta. All the mining debris raised the river beds such that flooding along the rivers was common place.
The constant muddy water in the Central Valley rivers from the hydraulic mining operations combined with a loss of spawning habitat
must have had a devastating impact on the salmon runs. Fish were of little concern when your house is flooding. Before hydraulic mining was stopped numerous debris dams were built on rivers to try and hold back the “slickens” as they were called. Undoubtedly, the mining debris washed down from the mountains was eventually dredged to build levees around the delta islands.
Rip and strip, the delta gets levees
By the late 1800’s reclaiming the nasty worthless tidal marshland of the delta was in full swing. With the help of steam powered clam shell dredges levees were erected on all the major sloughs and rivers in the delta. The 700,000 acres of tule marsh were reclaimed for agricultural land with 1,100 miles of levees.
Salty ocean water intrudes
While the levees protected the newly created farm land from flooding, they did nothing to stop salt water intrusion from the ocean. In the dry years of 1931, 34 and 39, salinity of 1000 parts of Chloride per million parts of water were recorded as far west as Courtland and Walnut Grove on Hwy 160, Terminous on Hwy 12 and the Upper Jones Tract along Hwy 4. Some plants can tolerate 600 ppm of Chloride, but irrigation water with upwards of 1,000 ppm is generally best left unused.
Here come the dams
After years of discussion and debate the great Central Valley Project was started in 1941. Even the original CVP envisioned a delta cross channel to move water south and repel salinity. From an overview of the CVP:
Water is to be pumped out of the Sacramento River into the Cross Channel, which will convey it southerly through the eastern edge of the rich delta where the two great rivers meet and mingle in a 550-mile network of interconnecting, tule-bordered, meandering sloughs and channels. Some of the fresh water in the Cross Channel will be turned out at various points to flush away the brackish, salty water that every so often creeps up into the delta sloughs from Suisun Bay. The water in the sloughs will be “sweetened,” as the farmers say, so the channels can be drawn upon for irrigation of the fertile asparagus and sugar beet fields.2
Dam water helps Delta
The big Cross Channel was never built. In its place was the much smaller Delta Cross Channel completed in 1951 to facilitate water from
the Sacramento to Mokelumne rivers. With the completion of the CVP and State Water Project reservoirs of Clair Engle on the Trinity, Shasta on the Sacramento, Oroville on the Feather and Folsom on the American rivers, there has been ample fresh water releases to repel salt water intrusion in the delta. The worst year was the drought year of 1977 when high Chloride content was measured across the islands of Twitchell, Brannan, Jersey, Bethel and Hotchkiss Tract.3
Last piece of the puzzle
The delta has always been both a blessing and a problem for California’s water system. On one hand, the natural channels, enhanced by the levees, was a natural, but not perfect, conveyance system for moving water from north to south. On the other hand, state and federal water agencies knew that that delta exposed their high quality water to potentially high salinity and agricultural drain water discharges. But because the delta already existed, it was always the last piece of the water puzzle to be considered.
More fresh water for the Delta
When California’s State Water Project was first considered a Trans-Delta System was proposed in 1957. Oddly enough, one of the features to move water around the delta were four 25 foot diameter concrete siphons that would transfer water under the Sacramento River from Collinsville to Antioch. Known as the Antioch Crossing:
The Antioch Crossing would then skirt the south-westerly edge of the Delta, finally terminating in the intake channel of the Mountain House Pumping Plant at approximately sea level. The total length of the crossing would be 33 miles. It would have the capacity of 17,000 second-feet, and would transport about 11,250,000 acre-feet per season.4
The current tunnel project estimates flows of 9,000 cubic feet per second.
Master Levees to reduce reverse flow from SWP and CVP pumps
Instead of a full blown concrete lined canal on the eastern side of the Delta, the 1957 California Water Plan proposed a series of master levees. Known as the Biemond Plan, the sloughs and rivers comprising the Delta Cross Channel would be strengthen and isolated from other waterways. The improved channel was to be siphoned under the Stockton Deep Water Channel. Salinity repulsion was also included in this plan:
Under operation of the Biemond Plan, salinity could be controlled at the western end of the Delta with an average outflow of of about 1,200 second-feet as compared to an average outflow of 3,800 second-feet for comparable control under present conditions. This major reduction in outflow would result from the reduction of the tidal prism, or the volume of water which flows into and out of the Delta during a tidal cycle, by severing many Delta channels from tidal action.4
What’s the Delta to me
It was in 1987 that I started studying the Sacramento – San Joaquin Delta. At that time the raging water war was over the lack of enforcement of the 1982 Reclamation Reform Act. The RRA stated that a farmer could only receive federally subsidized water for the first 960 acres; water used to irrigate any remaining acreage would have to be purchased at full price. The subsidized water transfers to irrigate new farm land on the west side of the San Joaquin Valley resulted in the wildlife disaster at Kesterson Wildlife Preserve.
Today the Delta struggles to maintain the right water quality and quantity to sustain salmon and several endangered fish. The combination increasingly polluted water from the Sacramento Regional Wastewater Treatment facility and the high pumping rates of the CVP and SWP have created a thoroughly nasty situation for the aquatic animals in the Delta.
So when folks say they want to restore the Delta, I wonder which version they are talking about. Do they want it restored to?
- 1850’s original tidal tule marsh land
- 1930’s reclaimed Delta that fought salt water intrusion during drought years
- 1950’s Delta that benefited from CVP water storage projects releasing fresh water to repulse salinity
- Today’s Delta that receives water from both CVP and SWP and intense interest from state and federal officials to strengthen the levees, save the fish and preserve the man made fragile levee system.
Is the Delta even worth restoring?
The Delta today is nothing like it was when Josiah Green built his first levee. But ever since agriculture has become the dominant money making industry in the Delta, both state and federal water agencies have sought to stabilize and improve the fragility of the delta islands and farming. Does the Delta even generate enough revenue to pay for strengthening the levee system by itself?
Its not the Delta’s water
The Delta has benefited from both the CVP and SWP project’s fresh water flows. Organizations that are opposing any new projects to improve the efficiency of water transfers through the Delta need to face the reality that without the water projects the Delta would have collapsed long ago from lack of maintenance and salt water intrusion. The water passing through the Delta, released from four different massive dams, was developed for agriculture and urban uses south of the Delta. The water passing through the Delta is neither northern California’s or the Delta’s. It is a public good developed for the benefit for all of California.
Are the proposed Delta tunnels the best solution for the water projects and the Delta? I don’t know. What I do know is that the Delta will never be restored or preserved to everyone’s dream. Fish are going to die or disappear altogether just like the Native Americans did when European settlers moved in. There will be more levee failures and I am not sure it is the California tax payers job to preserve farmland that used to be tule marsh. While the Delta is beyond restoration, we might be able to preserve its current status if all the interested organizations would just compromise a little.
Salmon who are raised in an estuary that mimics the early Delta marsh lands grew quicker than their counterparts being raised in a river system. The latest research by the Center for Watershed Management underscores the vital role the Delta played in maintaining a healthy run of salmon. The proponents of “Restoring the Delta” really want to maintain the Delta for their pleasure and profit. A real restoration would return a good chunk of the Delta to tidal marsh that acts as a nursery for so many aquatic plants and animals.
1. Clarksburg Delta Community by Shipley Walters, Yolo County Historical Society, Woodland, 1988
2. The Central Valley Project, Pg. 125, California State Department of Education, Sacramento, 1942
3. Sacramento-San Joaquin Delta Atlas, California Department of Water Resources, August 1987
4. Bulletin No. 3 The California Water Plan, Department of Water Resources, May 1957.