Tuesday, April 30, 2013

New PPIC Survey Makes A Strong Case for a No-Tunnel BDCP Alternative

The latest PPIC Delta report includes the results of an interesting survey of scientists and stakeholders on options to improve the Delta ecosystem. 

Looking at the key table of findings (table 2, page 14), the tunnels are down in the bottom right of the PPIC table, low potential impact for fish, low scientific consensus, and high cost.  It is the worse possible outcome in this ranking (upper left quadrant is best, lower right is worst).  Nevertheless, the PPIC calls the BDCP "promising" even though it is completely focused on the lowest ranking, most controversial option, and unnecessarily ties many of the more valuable, less costly, and less controversial habitat measures into a package with the tunnels.

As I have stated repeatedly, the ESA does not require the tunnels!  The state can and should develop strong no-tunnel options for the BDCP.

Although the tunnels fared terribly in their survey, the PPIC does not highlight that conclusion.  Instead they offer reasons they think the tunnels are better than they look in this ranking.  For instance, they talk about how the measures interact with one another, but they do so in a biased way - pointing out how the tunnels might support some measures while omitting how they work against other measures.  For example, on page 14, they state "If managed for conservation objectives, a tunnel could facilitate more variable flow patterns (#20) and reduce entrainment (#16)—two actions scientists consider quite promising."

What is the offsetting factor that they leave out?  The tunnels conflict strongly with the strategy of reduced exports (#17) which was also one of the highest ranking options for effectivness.  Their study finds that reducing exports has both higher environmental benefits and lower costs than the tunnels, thus I find it strange that they keep advocating the tunnels over reduced export strategies.  It is clear that exports will not be reduced with the tunnels, and will likely be increased from current levels.

Two other quick observations from the new PPIC report:

1.  Water exporters received, by far, the lowest grade for scientific knowledge of any of the stakeholder groups.  They even got a negative score for 2 out of 3 categories!  At least the Delta folks got a passing grade.  Table 7 from this supporting report has the results.

2.  The cost of the tunnels are only $$$!  Why did they use these 3 cost ranges with symbols? , $, under $10m annually, $$, 10m - $99m annually, and $$$, is $100m or more.  Why didn't they put numbers for the estimated cost ranges in the table?  And if they are going to use symbols, they must have a consistent meaning.  This is the kind of PR garbage that professors routinely mock in the first week of statistics.  It makes it look like the cost of the tunnels are not that high, even though they are orders of magnitude higher than measures that received the same symbolic rating.  It is reminiscent of the early BDCP screening studies I criticized for their biased, pro-tunnel analysis.  See this old post, "Would BDCP staff accept dots instead of dollars in their paychecks?" 

If a $ equals an annual cost of $10 million, then the cost of the tunnels is not $$$, but ranges from approximately

$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ to


  1. Jeff,

    Many things in the new PPIC report are worth careful consideration. The Joint Powers Authority suggestion is something that it may come to.

    And have to say, your analysis of using dollar symbols was $$$$$-less.

  2. John,

    There is lots of useful stuff in this report, and I didn't get into the governance issues at all.

    Looking at their survey results, the two things that stood out the most was the poor performance of the tunnels in the rankings, and that the exporters stood out - not even close - as the stakeholder group that rejects the scientific consensus. However the conclusions regarding these issues were limp - the lousy performance of the tunnels is downplayed and rationalized - and the exceptionally lousy understanding of science in the export survey group is lumped together with other stakeholders in the dull observation that stakeholders look out for their own interests.

    While their reports are getting better, the PPIC still retains its pro-tunnel anti-Delta bias in its interpretation of their own data.


  3. With all due respect John, I think this report is mostly hand-waving. Surveys like this are entertaining but are hardly scientific. I think that it is a bit strange that folks who propose science-based management rely on polls! I agree with Jeff that in some ways the PPIC reports are getting better - their report on ground water storage was very good - but why don't they seriously consider alternatives to the BDCP such as that described in your latest blog?

  4. Bob,

    A survey of scientists like this is actually quite useful to policymakers. Not unlike economic forecasts and policy analysis, the scientists are making an informed estimate of probable effects of actions. There will be some informed disagreement, and a survey that shows the level of consensus and uncertainty is a useful way of summarizing that knowledge. I think the table is a very useful summary.

    The unfortunate hand waving is in the PPIC interpretation that the survey results are anything but a disaster for the tunnels and BDCP. They call BDCP "promising", but their survey shows pretty clearly why it is broken. If you started with their survey results summarized in this table as a high-level summary of scientific knowledge and costs of Delta options, the objective conclusion would be to start with no-tunnel options. The worst approach would be the BDCP approach of building all major efforts for improving the Delta around the tunnels.

    Even worse BDCP puts the stakeholder group with the lowest ranking for scientific knowledge in charge of a process that is supposed to be science based.

    The proposals to create a joint powers authority for science could help a little - but doesn't address the fundamental flaws in BDCP's design and governance.


  5. That's my fear - that the results of an unscientific poll will be used by policy makers. Polls like this in general, and this poll in particular, tend to represent "group think". Respondents will say what they think is fashionable. A similar poll on climate change issues might show a consensus which is in fact incorrect and not supported by data. Show me the data!

  6. Hi Jeff - good blog. I read that Ellen Hanak of PPIC noted that reducing the fish slaughter at the pumps is one of the primary rationales behind the tunnel project, suggesting that some scientists might be supportive if they conclude the tunnels will accomplish that goal.

    Is there anything scientific you have seen that quantifies the impact to salmon from lack of fresh water versus how many salmon are killed due to entrapment? Most reports state that the key stressor is lack of fresh water. If the exports were reduced back to the 1990's level or less the fish would probably recover regardless of any other action.

    I haven't read what percent of the salmon decline is due to entrapment alone versus lack of fresh water flows. Have you come across anything like that?

  7. Jan,

    Maybe a fish expert will drop by to answer your question in detail.

    I don't know if you have quoted Ms. Hanak properly, but if you did, I expect that some fish scientists would be insulted by the suggestion that they don't recognize the entrainment and other benefits from changing the point of diversion. The biologists I have spoken with acknowledge that benefit, but are concerned that the tunnels create a very large new problem for fish - getting past the massive new intakes on the Sacramento River that will be sucking out 1/3 of the river flow. Again, don't quote me, ask a fish expert.


  8. Deirdre Des JardinsMay 1, 2013 at 11:18 PM

    The core problem with BDCP is that the science and the models are showing that the project won't work. To get enough water out of the North diversions to justify construction, the operations have to pump during key migration and spawning times for salmon and other fish, with unacceptable impacts.
    There is also the fundamental issue of needing to increase Delta outflow to Suisun Bay and San Francisco Bay to restore habitat for Delta smelt and other pelagic fish. Moving the point of diversion doesn't change that.