re: Experts on Coastal Erosion

Look on google maps at the area between the Atchafalaya and MS River outlets. That will show you the effects of controlling the flow of the MS river. Even in my lifetime of 36 years Terrebonne Parish is almost unrecognizable from my childhood. The coastal marsh on the eastern side of the parish is all but gone. Last island is a sand bar compared to what it used to be. Where my great grand parents raised cattle there is now 3 feet of water....

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but I was always under the impression that if it's building there after the addition it means that it's starving an area that used to get sand.

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You may be right, but to me, it functions the same as a terrace (neither of which is extremely effective at building land). The sand is being captured there because the current is reduced behind the breakwater.

I'm not sure where it would be "robbing" sand (really silty sand or something along those lines) from, but because of the channelization of most of our rivers, and jetties extending out into the gulf, most of it is lost anyway. I'm all for capturing what we can, especially on the Cameron coast. There are areas where the beach is 10 to 20 ft wide near the highway. One more strong hurricane, and what was once highway will be in the Gulf.

You may very well be right. Those sediment and current dynamics aren't my expertise, even though I have books on them and have read on the subject.. Any of that passive stuff is a waste of time in my opinion. Just fire up the damn dredge and get to building. We don't have time for "techniques" that take 10+ years to show any measurable land gain.

Nor do we have time for 5 and 10 year studies. The time for studies is over. If we don't know by now what techniques will work, then there is no hope for our coast. The only "studies" that should be done now are site evaluations to determine if a site is worth restoring and will be successful. These projects are too expensive to fail, and so much rides on their success.

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The time for studies is over. If we don't know by now what techniques will work, then there is no hope for our coast. The only "studies" that should be done now are site evaluations to determine if a site is worth restoring and will be successful. These projects are too expensive to fail, and so much rides on their success.

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Well said

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The only "studies" that should be done now are site evaluations to determine if a site is worth restoring and will be successfu

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you do know that is what the most recent studies have been about, right?

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National Marine Fisheries is just as bad about impeding restoration

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A-fricking-men. They are so short sighted that often, present-day impacts to a manatee outweigh the fact that the no-action option of letting the entire cost sink will mean no snails, birds, turtles, shrimp etc.

As far as the Corps goes, there are two main ways the muck up the speed at which restoration moves: land rights and permitting.

Land Rights: although technically they dont have to do this, in effect, the Corps requires that any restoration project they perform acquire the land in fee. In very simple terms, if the Corps is going to leave something permanent at the site, whether it be dirt, culverts, signs, whatever, they want to own the surface rights. Seeing as over 80% of coastal marshes in LA are privately held, this creates litigation nightmares. The state gets around this by entering in to easements with landholders where the landowner retains surface rights for trapping, leasing for waterfowl, etc., but they simply are precluded from excavation or development of the restored wetland. The corps can do this, but opts not to.

Permitting: I could go on for days. Section 408, 410, 404 reviews. There are a million ways for them to drag out things like Environmental Impact Statements, permitting of modifications to federal projects (if someone like the state wants to modify a levee to put a diversion gate in or run a dredge pipe over or dredge a federal channel, Corps will review in an anal manner). In a nutshell, if there is a chance for the Corps to throw wrenches into the process and slow things down by years, they will. Funny thing is, when they do internal projects, they largely ignore all of their own rules. The whole idea behind a state of emergency would be to replicate post-Katrina conditions where the Corps basically said they would suspend all of their rules in order to build shite fast, and would address mitigation later. They are just getting around to mitigating for post-K levee construction now.

OP: email man.in.the.stadium at g mail dot com

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Another problem, that few bring up when they discuss sediment diversions, is that the River isn't carrying the sediment loads that it once did due to dams on tributaries upstream and whatnot. So, blowing the levees at a certain point would obviously help, but it wouldn't be some "overnight" miracle. You're talking about a process that occurred over hundreds to thousands of years with less sediment coming down River now than when it was created.

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This is largely overblown. Does it carry less than historic? Yes. Has that downward trend flat lined? Yes. Are there still millions of tons of sediment moving down the river that we could easily use? Yes.

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The southwest coast tells a different story. You look at where the breakwaters are, and there is beach building behind them. Where there are no breakwaters, no beach is building.

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The problem with rocks that people don't realize is this: loss of beach or marsh edge due to erosion is a small contributor percentage-wise to overall land loss. If you had to attribute land loss contributions in a pie chart or something to that effect, there would be 2 main causes-edge erosion and subsidence/sea level rise. Edge erosion contributes a fraction compared to the fact that our entire coast will be inundated if we effectively sink several feet due to subsidence and SLR. We can rock every foot of Cameron Parish, but if the average elevation is less than a foot or two, and we sink by a few feet, all the land, including the rocks, will be underwater. Rocks have their place, but are a short-term, situational solution.

not arguing, sorry, should have restated to agree.

agree on saltwater, but if we see even the lowest of the recent master plan's RSLR values, it will be moot. I guess one could call it either saltwater intrusion/saltwater inundation, but it is semantics...either way it would all be underwater, regardless of what control measures are put in place out west.

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This is largely overblown. Does it carry less than historic? Yes. Has that downward trend flat lined? Yes. Are there still millions of tons of sediment moving down the river that we could easily use? Yes.

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I did not say there wasn't enough sediment to build any land. I was noting that historically there was a lot more sediment with which land was built. It is not overblown if you're trying to discuss what the diversions could/would do today versus sediments that built the land in the first place. Obviously there is plenty of sediment still coming down River, but according to USGS that's still half of what was coming down before 1950. (Much of the decrease was due to a single dam on the Missouri River, and interestingly soil conservation practices on ag lands also contributed. Conservation hurts the coast!)

Where did you work at? There is the Plant Materials Center doen in Galliano (or is it Golden Meadow?) now that does all of that, but I don't know how long it has actually been around.