Friday, July 1, 2011

The 4th of July and Delta Levees

[Youtube video of Delta fireworks removed for faster blog loading.]

Should Delta levees be upgraded and then repaired if they fail? Should significant areas of open-water caused by permanently flooded islands be part of the Delta’s future? It is a reasonable question and as one who believes in the value of cost/benefit analysis, I like the set-up of the levee decision analysis paper from Suddeth, Mount and Lund of UC-Davis. Unfortunately, their conclusion that the majority of Delta levees aren’t worth the investment or recovery is way too strong given the relatively low assumed values of land, infrastructure and the variety of things that they have not measured, including recreation impacts. Luckily, the editor of the SF Estuary journal appears to have forced them to include more sensitivity analysis results before publishing their paper, a result I consider better than outright rejection in this case since we can see more scenario results from a paper that was already influential.

This picture from their paper emerged from a scenario with better land and infrastructure values, and is enough to move the conversation forward.  The key result is the 6 central Delta islands that would be converted to open water over time.

Jeff Mount, a member of the Stewardship Council’s independent science board, apparently agrees, since he put the same map forward in a letter to the Stewardship Council. In my view, their earlier analysis did establish something useful: the discussion of do not resuscitate lists can be narrowed down to these six islands, plus maybe 2 or 3 very small islands scattered around the Delta like Deadhorse or Fay. (Note: If they considered the new Stockton Water Supply project, Empire Tract (#16) would be removed and it would be a five island open water area.)

In the Economic Sustainability Plan, I directed our team to take a serious look at this future open water configuration.  Given the absence of key infrastructure in this area, few residents, and low-value agriculture, these islands certainly rank the highest on the candidate list of places we might allow to be converted to open water.  On the downside, there are concerns about the impacts on levees on surrounding islands, water quality concerns related to increasing organic material for municipal and industrial water intakes. 

I thought recreation would be the wild card, and have been a little surprised at the almost universally negative response from recreationists, owners of recreation related businesses in the Delta, and recreation experts who have been studying the area for years. 

One of the first things I heard was, “It will ruin the 4th of July.” I am usually out of town on the 4th, and didn't know Barron Hilton has been hosting a large fireworks show off Mandeville Tip since 1958 near his duck club on Venice Island.  This location is directly in the middle of this open water scenario.  It is the biggest weekend of the year for Delta recreation.

The next thing I learned is that this area is the most popular area for boating, and that about half of Delta marinas surround the immediate area and in most cases would be potentially negatively impacted by the loss of wind/wave protection and the necessary levee improvements on adjacent islands. I didn’t go to all the recreation focus groups, but my understanding is that it got a very negative reaction from boaters and marina owners who anticipated high waves and winds would drive them elsewhere, possibly out of the Delta all together. Since this is the most popular area for boating and boating is by far the most important recreational activity to the Delta economy, it seems this plan could have harmful negative economic effects that aren’t considered in the Suddeth et. al. models. Few people seemed to think that sailing or other recreational opportunities would fill the void.

The last thing I learned is that it could be bad for hunting. I spoke with one farmer who grew low-value crops in this area, and I asked why he didn’t grow different crops. He explained that corn prices have in fact made growing corn high value, but the real answer was that in the Delta there are farmers, farmers who also hunt, and avid hunters who do some farming when it isn’t duck season.  He considered himself in the latter category, and insisted he would grow corn if it were 10 cents a bushel, always has, because it leads to good duck hunting and that is the top priority.  It seems there is more underlying the value of land than just the value of crops.

So, how much is all that worth? I don’t know for sure, but it is a potentially big deal, especially if it really is as negative for boating as our initial feedback suggests. We have learned that levees that protect low value agriculture may be supporting high-value recreation.

Personally, I would like there to be less talk about Delta recreation/tourism as a driver of income and jobs, and more talk about it just being unique and fun. That’s worth something, but it isn’t anywhere in the computer models about Delta levee decisions. Perhaps it should be.

Have a safe and happy 4th everyone!

[Youtube video of crazy Delta jet skier removed for faster blog loading.]


  1. Your point regarding value of recreation in the delta is well made. As you allude to, value cannot always be measured in dollars.
    I continue to run a small marina/ RV Park in the primary zone of the delta that has been in my family for 45 years.The enthusiasm and surprise displayed by first time visitors helps to bouy the spirit of those of us who endeavor to provide quality access to the public.I like to think that if we can get you in the door the delta sells itself.People who visit come away with a new found respect and are not so quick to write the delta off. As you are discovering, when you flood an island you don't just lose valuable farmland.
    As a suggestion to anyone who wants to learn what is at stake from a recreation point of view I would highly recomend reading "Dawdling on the Delta" by Hal Schell. It is an excellent read and captures the spirit of the delta quite well.

  2. This characterization of our work on Delta levees is just silly and alarmist. As one can clearly see from the map, we do NOT say that most Delta levees are goners. However, many Delta levees in the central and western Delta do not seem to be economical to repair when they next fail. But this leaves most of the Delta, even much of the subsided land area, in pretty good shape, as can be seen on the map.

    This conclusion seems well supported by the sensitivity analyses done for our 2008 report, and expanded for the journal version (2010).

    Our calculations seem to agree with recent Delta history. The last 3 decades have had 3 island failures. For two of them (Mildred and Liberty islands), the owners abandoned them following levee failures. Mildred Island is now a fishing and boating spot of some renown. Liberty Island is supposedly a refuge for delta smelt. Jones tract was repaired, at great state expense, and has considerably higher economic value.

    The Delta will continue to be a beloved place, and rightly so. But some parts seem likely to change.

  3. I don't think that this post says that every small island must be repaired, and indeed the Mildred Island case is why I say I have been surprised by the extent of the negative reaction.

    It seems that it is the large islands, especially continguous ones that would create a very large area of open water, that is a concern of recreationists, not a few small ones scattered about.

    What is silly about asking the question about recreation effects?
    It raises an important question, and is a good research topic.

  4. Unknown, you seem in your discussion to overlook the negative impacts of flooded islands on adjacent islands, the negative impacts on water quality and the overall negative impacts on recreation, not to mention the expense of hardening or re-routing any infrastructure that is impacted. Not to mention that it is the policy of the State to protect, maintain and enhance the Delta. Your own work correctly points out some of these issues as "impediments" to flooding islands and acknowledges that the ecosystem benefits are uncertain. Who's being silly?

  5. Oh, I forgot to point out that citing the flooding of Liberty Island as being advantageous to the Delta ecosystem is misleading. Liberty Island was part of the Yolo Bypass with height limited levees and was at the optimum elevation for conversion to tidal marsh habitat. It is wonderful that the positive effects have exceeded all expectations but the results from Liberty Island are not transferable to the deeply subsided islands.