http://www.nola.com/news/gulf-oil-spill/index.ssf/2010/07/sand_berms_a_dubious_solution.html
Sand berms a dubious solution:
A guest column by Len Bahr
Published: Monday, July 05, 2010, 6:00 PM
Contributing Op-Ed columnist Contributing Op-Ed columnist
The coast of Louisiana occupies North America’s largest delta, which has
been rapidly shrinking and sinking for a century. River channelization,
flood levees, upriver dams and coastal oil and gas production continue to
take their toll. But a decade from now, the unprecedented discharge of
perhaps 100,000 barrels a day of oil directly off our coast for months on
end may prove to have been as damaging to the delta as these historic
stressors.
Obviously no handbook exists on effective responses to such a massive oil
release. This policy vacuum, combined with panic and desperation among
coastal residents, created an irresistible opportunity for grandstanding on
the part of our ambitious young governor.
In this highly charged political climate it is not surprising that Bobby
Jindal would opt for responses to the oil crisis based more on drama than
effectiveness. For example, he would likely prefer to be videotaped in front
of a massive, noisy dredge boat stirring up mud than observing small craft
silently skimming the water surface.
Thus, the governor’s most widely discussed response to the coastal oil
assault is to pile up defensive sand barriers. The rationale for this action
is to intercept the oil before it can contaminate the wetlands that hold
delta sediments in place, nourish fish and wildlife and protect people from
storms.
About 80 miles of 6-foot-high sand berms are now under construction on the
lower east and west sides of the Mississippi River. The total quantity of
sand required to complete this project is said to be 56 million cubic
yards — the equivalent of 11.2 times the volume of the Superdome!
Some of this (sacrificial) sand is being dredged from the lower river
channel, but most is being mined from old barrier islands that have sunk
beneath the sea. Although the dredging doesn’t leave a visible change at the
surface, it alters the subsurface profile of an area and reduces the bottom
friction that formerly absorbed hydraulic energy during approaching storm
surges.
On the basis of 22 years of academic training and experience in coastal
science and 18 years of policy experience in the Governor’s Office of
Coastal Activities, I’m strongly opposed to the governor’s sand berm project
for the following nine reasons:
1) Absence of science: Vague plans for the sand barriers were hastily drawn
up by “outside experts” from Holland, with no input from Louisiana coastal
scientists. Project details subsequently released have been universally
panned by these scientists.
2) Questionable justification: The sand dredging project was proposed by and
heavily lobbied by vested dredging interests, and it reeks of potential
conflicts.
3) Opportunity cost: This emergency and temporary project will deplete and
waste finite sand resources needed for a credible barrier shoreline
nourishment project.
4) Environmental cost: Dredging holes in the very delta that we’re trying to
restore is irrational.
5) Changes to natural flow regime: Attempting to barricade tidal passes
speeds up water velocity, causing barrier island erosion and potentially
sucking even more oil into the estuary.
6) Lengthy construction time: The contractors project a completion date nine
months away, by which time deflecting BP oil could be a moot issue.
7) Sand berm fragility: Sand-filled Hesco baskets (a type of sand berm)
completed three weeks ago by the Louisiana National Guard along Holly Beach
to protect against BP oil washed away like sand castles during a glancing
blow by Hurricane Alex.
8) Dubious benefits: A huge volume of crude oil has already drifted into the
very marsh areas that would supposedly be protected by sand barriers.
Completed berms could trap rather than repel some of this oil.
9) An alternative active response: Whether or not BP pays for the sand
barrier project, there are more effective and risk-free ways to spend $350
million. For example, I estimate that for that amount 2 million tons of
oil-absorbing hay could be spread on the oil by boats and planes, soaking up
perhaps 4 million tons of oil, then raked up by shrimp boats for onshore
disposal.
I’m not alone in challenging this project, although I can afford to be more
vocal than most of my science colleagues. Many of them, along with their
employers, fear the financial consequences of alienating Gov. Jindal, who
tolerates no criticism of his sand berm fantasy.
Len Bahr, Ph.D., is a former LSU marine sciences faculty member who served
18 years as a coastal policy adviser to Louisiana governors from Buddy
Roemer to Bobby Jindal. He edits LaCoastPost.com. His e-mail is
leonardbahr@gmail.com.
Special thanks to Richard Charter