The Proposed Periipheral Canal and the Delta
This was published in the Lathrop Sun Post today. I think it is a revealing look into the consequences of constructing this water by-pass canal around the Delta. Mr. Hildebrand points out that there are no winners if it is built, long term there is only losers. Also the damage inflicted by it, if completed,will have everlasting effects of disasterous proportions, both for the health of Californians in general and specifically Delta water quality. Harley
Peripheral canal around Delta is a bad idea Written by Alex Hildebrand/South Delta Water Agency
By Alex Hildebrand
California is facing a serious problem. Its population has outgrown its developed water supply. We are dependent on an unsustainable overdraft of groundwater. The state’s population is anticipated to grow by 6 million people in the next 10 years.
Unfortunately, the state has no credible plan to provide the water needed to meet the needs of this increased population. A peripheral canal would merely reallocate the shortage among water users and uses. It would cost billions of dollars and would have serious unintended consequences that would be largely irreversible. It would provide no net benefit to the state, and even the winners would later find themselves paying more for water and the adverse impacts that were redirected.
Here’s why:
Fresh water inflow has already been greatly reduced by bypassing exports south from Friant Dam west from the Tuolumne and Mokelumne rivers around the Delta. The inflow has also been reduced by the upstream consumption of water for urban and agricultural uses. A peripheral canal would keep more Sacramento River water out of the Delta. This increased loss of fresh water would inevitably cause a substantial increase in the salinity in the Delta channels. Water in the Delta channels would then be deemed too salty to export. The peripheral canal would have to convey all the water that is exported south and west from the Delta channels.
As a separate structure, the peripheral canal would be a barrier to flood waters from south and east of its alignment. During major floods that exceed the capacity of the San Joaquin and Mokelumne channels, the flood stage would increase against levees that protect tens of thousands of homes.
If billions of dollars were spent on a peripheral canal, those funds wouldn’t be available to improve Delta levees and to implement measures that could impede the flow of San Francisco Bay water into the Delta in the event of multiple levee breaks. (This multiple breach threat is only a problem if levee breaks occur at a time when outflow to the bay is not maintained by flood flows.) The political interest in protecting the Delta would be greatly diminished, even though that protection is required by statute.
If the basic configuration of Delta channels and land uses were not maintained, there would be an increase in the tidal actions that bring bay water into the Delta. Numerous peripheral canal proponents propose that levees be breached and/or allowed to fail for lack of maintenance or repair. As each island flooded, it would increase bay water encroachment by tidal action and also the net consumption of water. It would also increase wave erosion on other levees. If the basic configuration were not maintained, the Delta would become a salty inland bay.
As the Delta became an inland bay, the levees that protect roads, houses, utilities, railroads, recreation facilities and so forth would experience substantial increased wave and seepage problems. Their ability to protect the public’s interests would be seriously diminished.
Delta agriculture produces food on about 500,000 acres. That production would be largely destroyed by increased salinity of channel waters and by the uncertainty of levee production caused by a peripheral canal. Agricultural Code 411 states that California must not become dependent on a net import of food due to failure to provide an adequate agricultural water supply. Using a peripheral canal to increase salinity and destroy half a million acres of food production in the Delta is incompatible with that mandate.
The salinity increase caused by a peripheral canal would cause a violation of most, if not all, of the state Water Resources Control Board’s salinity standards. The circumstances creating such high salinities would turn portions of the Sacramento River into a large null zone where predation and temperature would further hurt endangered species.
The reallocation of an inadequate water supply and other consequences of a peripheral canal would violate the Delta Protection Statutes, water rights law and the Environmental Protection Act.
The peripheral canal would promptly increase salinity in Delta channels higher than it has been for centuries. It would also cause a major change in the velocity and direction of flows in Delta channels. It cannot be fully determined in advance how this would affect the fishery and other aquatic organisms.
The peripheral canal would have to have a massive fish screen at its inlet. We do not know how the redistribution of fish in the Delta would affect the loss of fish at those screens. As the Delta converted to an inland saltwater bay, the fishery would again be greatly altered.
Instead of spending billions of dollars on a peripheral canal, we should focus on how to preserve the basic configuration and benefits of the Delta; how to preserve the level of exports available after protecting the Delta; how to increase the capture and retention of flood waters; and how to provide the water needed for the people, for production of agricultural products and for the environment. A coalition of in-Delta experts have an initial draft of a proposal to protect the Delta and the export of water that is excess to Delta needs without using a peripheral canal.
A peripheral canal would do nothing to address the basic and rapidly growing shortage of the developed water supply. It would merely reallocate the shortage in that supply, with disastrous consequences to the Delta and its many public and environmental benefits.
n Alex Hildebrand, a rural Manteca farmer, is a South Delta Water Agency engineer.
