The multiple functioning bypass
...the following probably belabors thoughts begun in the previous post…edited 11:30PM 12/8…
I began the blog with the intention of staying focused on the Delta. But in my discipline, understanding the limits of a problem depends on knowing its extents. Staying focused requires good peripheral vision.
This is the only way to begin to understand interrelationships in a complex natural and cultural ecology. And to imagine possible solutions. That is why the Grasslands Bypass Project was so intriguing, since it seemed a promising hybrid of remediation and production, at least it did in my imagination.
Legal issues and facts are part of this ecology. Mike Wade provided a record that pretty convincingly answers the legal question of whose responsibility it is to “provide drainage services” to the owners of the salt-laden land he represents. It seems that responsibility falls to the alternately despised and depended upon government.
It falls to the technical and spatial apparatuses and budgetary capacity of government to find ways to implement this charge. But in this context (as in many others in these anti-tax days) its agencies are in a most difficult bind, well-expressed by USBR Commissioner Keys in 2005:
Seven action alternatives are evaluated in the Draft EIS. The alternatives can be grouped by their final discharge location - Delta, ocean and in-valley evaporation. Four alternatives - Delta discharge at one of two potential locations, ocean discharge, and in-valley evaporation, provide drainage service to all 379,000 acres of land that require it. Three additional alternatives combine in-valley evaporation with varying levels of land retirement. Land retirement, defined as removal of lands from irrigated agricultural production, would reduce drainwater production and thus reduce the size of the in-valley treatment and disposal facilities. The alternatives would cease irrigation on 92,600, 194,000 and 308,000 acres respectively, reducing drainage production from 70,000 acre-feet per year to 61,000, 45,000 and 27,000 acre-feet respectively.
The estimated construction costs identified in the draft EIS of the alternatives range from $589 million to $918 million. On a present worth basis, which is the combined construction and annual operation, maintenance and rehabilitation costs presented as a one time cost, three full-service alternatives - Ocean Disposal, Delta - Chipps Island, and In-Valley Disposal are nearly identical at about $562 million. The In-Valley Disposal with Land Retirement alternatives range from $626 million up to $857 million on a present worth basis. All of the alternatives exceed the spending limit authorized under the San Luis Act.
That last sentence is worth reading twice, in a post-2008 economy. Thanks to Chris Gulick for sending the link.
The extents of the Delta’s ecology applied here means that it is inevitable that the water and toxicity issues of the San Joaquin Valley and Tulare Basin must be understood as they impact policy making for the Delta. These extents eventually scope back to the limits of the Delta, and to a less public rationale for why a peripheral canal or tunnel is inevitable.
The Grasslands Bypass Project is extolled as an example of a successful experiment at controlling selenium in Salt Slough and managed wetlands in the area just downstream from the Westlands Water District. An EPA article, titled Grasslands Bypass Project Reduced Selenium in San Joaquin Basin may be technically true, but is highly misleading.
Yes, the drainage infrastructure reroutes toxic water around Salt Slough and the managed wetlands, but it does this by concentrating it in Mud Slough. It is a useful and to a degree successful experiment that foreshadows what a rerouting infrastructure writ large might be in the Delta.
From a 1998 UC report:
The Grasslands Bypass Project in the western San Joaquin Valley of California was conceived as a means of diverting selenium-contaminated agricultural drainage water from fresh water channels serving Grassland wetlands.
Sediment selenium concentrations are anticipated to increase in Mud Slough as a result of increased selenium concentration and loading, and to decrease in Salt Slough, which no longer conveys selenium-contaminated agricultural drainage.
So, the question remains: okay, you created a way to isolate it, but what do you do with the stuff you’ve collected?
Microcosmically (I know, but it should be a word), is Salt Slough the canal/tunnel, and Mud Slough the Delta?
I increasingly have the sense that the (unspoken, but perhaps equally important) function of the tunnel/canal would be no more about ensuring water security for CVP and SWP clients than it would be about bypassing the selenium-, boron-, and mercury-laced waste water to be deposited in the (South?) Delta.
The government must “provide drainage services,” and dumping back into the Delta from the South Valley is definitely the cheapest option if one doesn’t include the cost of the Delta’s bypass infrastructure, which is say $15-30 billion dollars.
It’s a win-win for everyone but Delta folks, and they know it.
Treating the Delta as a drain was the original plan, after all. It remains arguably the least expensive one, just to let the San Luis Drain do what it was intended to do in the first place, which was to dump west side drain water into the “Contra Costa Delta.”
Three types of bypassing function are in play in or near the Delta.
1/ The Yolo Bypass is a time-based function related to flood control. It has the happy side benefit of providing lots of seasonal marsh habitat.
2/ The Grasslands Bypass Project separates and collects toxic water and allows the perception of improvement elsewhere in the form of measurable reduction of selenium’s presence. I like happy side benefits, and wanted so much to like this project, but it is very possibly a smokescreen. Allowing postponement of inevitable solutions that don’t involve taking hundreds of thousands of acres of ag land on the westside out of production benefits everyone scrambling to find a final solution when all of the choices suck.
3/ Bypassing in the Delta via a canal or tunnel would depend on a three-dimensional system of siphons, where two entirely separate systems of water, one headed around and out, one headed in, are allowed to move independently of each other.
Bypassing is usually a form of reactive problem-solving. That seems to be so for these three case studies.
As for judging the extent of costs involved with draining selenium into the Delta (or any of the other alternatives) and creating a bypass to avoid its reintroduction into the export water supply, I await the cost-benefit analysis Jeff Michael has repeatedly asked for.