Monday, December 19, 2011

Governor Brown should have attended the Delta Stewardship Council meeting last Thursday

Last Thursday, Governor Brown was at a climate change conference in San Francisco.  According to the Sacramento Bee, he said regarding a potential peripheral canal/tunnel, ""It will cost money," he said. "But if we don't do that, and the levees collapse in one of these extreme events, we could run out of fresh water."  Yesterday, in a statement in support of BDCP he said, "We shouldn’t wait for a natural disaster to force our hand... This agreement takes us in the right direction to protect California’s water supply."  Governor Brown is clearly worried about earthquakes and floods in the Delta and their implication for water exports.

If he were at the DSC meeting last Thursday, he would have heard Bob Gilbert, a reknowned geotechnical engineer and risk management expert from the University of Texas.  Dr. Gilbert was on the peer review team for the DRMS study a few years ago, and chaired the recent peer review for the Delta Protection Commission's Economic Sustainability Plan.  He made these comments:
"seismic risk to the water supply really is not that significant."
"If you look at the consequences... the net present value over a 100 year window of water supply losses is about $2 billion ... does not in any way justify spending $10 billion on conveyance."
"reliability of water supply due to earthquakes is not a big threat"
(Note: the basis for the comments are the DRMS studies, quotes are from my meeting notes and may not be exact)

Dr. Gilbert was there to review the Economic Sustainability Plan, and I should note that the context of these remarks was not criticizing BDCP, he was criticizing the DPC's Economic Sustainability Plan claim that seismic levee upgrades would improve water supply reliability.  But it is interesting that much of the criticism was based on the fact that the seismic risk isn't that big (expected annual loss of $20 million a year if you believe the DRMS earthquake probabilities), and the bigger water supply risks are environmental rulings and water quality. 

In my remarks, I chimed in with a few additional relatively unknown findings from DRMS:
  • Water export interruptions are only 20% of the economic cost from a large Delta earthquake that floods 10-30 islands.  (See earlier post on this here.)
  • Water export interruptions are less than 2% of the economic cost from Delta flood events.
  • Water export interruptions cause 0% of the loss of life from Delta earthquakes and floods.
This is why DRMS found levee investments have the highest benefit-cost ratio of all Delta risk reduction strategies (yes it's true, although DWR did not report the benefit-cost ratios), because levee improvements protect all the economic risks (energy, transportation, property, farmland, human life, recreation, water quality and water conveyance among others).  In contrast, the isolated conveyance strategy spends an enormous amount of money protecting against a relatively small portion of risk.

Governor Brown needs a better understanding of the risks from natural disaster in the Delta.  On an encouraging note, this KPBS report on the climate change conference suggests he is unbiased and knows he still has more to learn about the issue,
The governor said under California law he's not allowed to say which proposal he supports until the report is released.
"In addition, I haven't really read the damn thing. And so I don't have a bias because I don't know what the hell it is," joked Brown.


  1. Have you received any response from any appropriate expert regarding your cost/benefit conclusions re canal/tunnel/levee upgrade?

    Based on your notes on Mr Gilbert's testimony, it seems like he may be a good person to start with.

  2. I have heard (indirectly) that the Resources Agency has said that it does not intend to do benefit-cost analysis on conveyance or habitat because it is not required by law.

  3. Come on Jeff, tell the whole story. As you even acknowledged at the Delta Protection Commission meeting regarding these same numbers, the risk assessment was only addressing (arguably) the structural risk to continuing to move water through the Delta, it does not at all include the "supply reliability" issue that is at risk from sea-level rise/salinity increases and most particularly the Endangered Species Act conflicts of the present system. Those are the real drivers that will affect water supplies into the future.

  4. Greg,

    Very correct, and I thought I noted that in the post as well as the context that I pulled it from. The context of the criticism of us is that seismicity is a relatively minor aspect of reliability compared to the ESA conflicts and water quality. Thus, even if it is earthquake proof you haven't fixed water supply concerns. I don't dispute that.

    The point of the post is that when asked about the Delta, most politicians respond like Brown did: there could be a disaster so we need conveyance.
    Earthquake and floods are a risk for so much more than water export. Thus, the appropriate response is there could be a disaster so we need flood protection investment, emergency response/preparation, etc. not conveyance.