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July, 2006


Simple Take-Home Misrepresentations About Bolinas Lagoon
By Gordon Bennett, Sierra Club Marin Group

The June 1 Coastal Coast contained an article by Don Slack (A Simple Take-home Message about the Bolinas Lagoon) that contained numerous mistakes, misunderstandings, and misleading statements.

Dark Age Prejudice
Don stated that the "Phil Williams Report shows the 50 year projection of the Lagoon as primarily mudflats and marsh", implying that this condition represents a significant change that is adverse. This is misleading on both counts. If you add up all the habitat types listed as mudflats and marsh in the 2/10/06 Report's Table 5.1 (pg. 83), you will find that the year 2000 total was 866 acres and the year 50 total is 869 acres, a totally insignificant increase of only 1/3 of 1%.

Furthermore, it is exactly these current mudflats and marshes that earned Bolinas Lagoon its designation as a wetland of international importance because they provide a healthy and highly productive base for the food chain that sustains the Lagoon's wildlife. In the past 150 years, 90% of the former marsh and mudflats around the SF Bay have been filled in out of ignorance and greed. More recently, million of dollars have spent to restore them. Readers should not to be taken in by the dark age prejudice that marsh and mudflats are "unhealthy" and the more recent fraud that the Lagoon ecosystem needs to re "restored" by destroying its greatest ecological assets.

No Closure
Don also claims "the Phil Williams Report predicts lagoon closure in about 60 years." This is mistaken. The 5/23/06 Memo (pg. 6) clarified that in year 2125 (119 years in the future, not 60) when the risk of closure would be greatest, the number of closures predicted was ZERO using the projected 2125 tidal prism of 2.0 MCY and its associated mouth width of 200 feet (Table 5-2 pg. 5).

Only by artificially plugging the 2.0 MCY calculation with a 300 foot mouth width associated with a tidal prism of 3.5 MCY was the report stretched to generate a "once in a decade" possibility (not certainty) in 2125. Even that artificial calculation is based on an out-of-date rate of sea level rise, whose updated figure will likely reduce even this artificially-generated possibility to zero. Of course, it is also just as possible that the Lagoon could close before you get to the end of this article, but it is also possible that hell could freeze over before you get there.

No Closure, No Way
Nevertheless, Don claims that unless "water flow in Easkoot Creek and Pine Gulch Creek increases to that of the Russian RiverÉBolinas Lagoon will likely experience permanent closure." This is a misunderstanding. As the 4/21/06 Memo (pg. 6) notes "the scouring power (of creeks) is typically an order of magnitude smaller than tidal flowÉwe confirmed this by calculating [that in Bolinas Lagoon] " typically a 1-day in 2-year flow event discharges approximately 0.4 MCY, compared to 3.5 MCY of tidal water discharged through the inlet. The three critical factors are tidal prism, inlet width and wave power; creek flow is virtually irrelevant.

Don also claims that unless "wave action at the Bolinas Lagoon reduces to that of Crissy FieldÉ Bolinas Lagoon will likely experience permanent closure." This is also a misunderstanding. The 4/21/06 Memo (pg. 6) notes that the Crissy Field closure projection used the appropriate measures of SF Bay tidal prism, inlet width and wave power for Crissy Field, just as the Bolinas Lagoon closure projection used the appropriate measures of Bolinas Lagoon tidal prism, inlet width and wave power for Bolinas Lagoon.

The Inconvenient Truth
The "inconvenient truth" is that over the next century, California estuaries, including Bolinas Lagoon will drown, rather than fill in, as global warming will cause rising sea levels that will ultimately outpace sedimentation. Preservation of some ideal Lagoon form would require that sediments dredged out in this century (to maintain deeper water habitats) would then need to be put back into the Lagoon in the next century (to maintain shallower water habitats).

Current concerns about the Lagoon mouth being kept open might then be translated into concerns about the Lagoon mouth being kept constrained in order to mute Lagoon tides and prevent rising seas from threatening properties from both ocean and Lagoon sides. One has to wonder whether, if all the effort that has been put into a "Restoration Project" had instead been put to reducing impacts from global warming, might both the Lagoon and adjacent properties be better off?

Human Causes on Both Sides
Lastly, Don recollects that Dr. Bryne stating that no intervention was needed. This is a mis-recollection. The 4/21/06 Memo (pg. 3-4) notes: The Draft Report does not make any recommendations with regard to interventionÉIf any intervention is justified, it should be on the basis that anthropogenic changes have significantly altered the natural trajectory of the lagoon's evolution with corresponding adverse ecological impacts." However, we should not repeat the Corps error that emphasized sedimentation but ignored sea level rise, by now over-emphasizing the human-caused impacts of sedimentation but ignoring the human-caused impacts of sea level rise.

While the construction of Seadrift, the channelization of Pine Gulch, logging and most significantly, global warming, have likely altered the trajectory of the Lagoon's evolution, the question remains whether these alterations are significant (e.g. they do not result in closure), whether they cancel out (e.g. the 1906 earthquake canceled the logging impact; global warming cancels sedimentation), and whether their mix of ecological impacts is overall adverse (e.g. salt march expansion is positive; eel grass loss is not).

Science or Prejudice?
Now that the Phil Williams Report has established a firm No Action Alternative, we need to move forward on a continuing solid basis of science, not just to protect the Lagoon, but also to protect against what could easily be a monumental waste of money if the proposed restoration projects are not carefully calibrated to the facts. Thus the Project's next steps should be to revise the 1996 Management Plan's Goals and Objectives, which the Technical Review Group found to be "unrealistic" because they were "an uncritical list of desired conditions that cannot all be simultaneously maximized."

Furthermore, these 1996 Goals and Objectives were based on the now disproven assumption that a naturally static and deep Lagoon needed to be "preserved" from filling with creek sedimentation from human impacts. New Goals and Objectives need to be updated based on the new information that a naturally dynamic and shallow Lagoon is filling with ocean sediment from natural processes

Patience and Understanding
That means more than just continuing patience on the part of the public; it also calls for a pro-active effort to understand the documents and participate in an educated discussion about setting new Indicators for Lagoon management to ensure ecological viability and natural evolution. Then these Indicators need to be compared against the No Action Alternative in the Phil Williams Report to determine whether intervention is warranted.

If intervention is warranted, then it will inevitably involve trade-offs in which both sides of the trade-off need to be clear and explicit. More of one habitat type means less of another. The relative value of each side of the trade will need to be assessed to determine if the trade is desirable. And the trade will need to be assessed in the context of the physical process that we now know drive the Lagoon's functions to determine if the trade is sustainable.

Informed discussion is much more likely to lead to appropriate action than mistakes, misunderstandings, and misleading statements.

Gordon Bennett, Chair
Sierra Club Marin Group

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