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The checkered record of wetland mitigation – the lesson of Downton Abbey

Photo from PBs

Photo from PBs

by Len Bahr, Ph.D.

Mit·i·ga·tion: noun: the action of reducing the severity, seriousness, or painfulness of something. Note that this definition does not include eliminating or permanently solving the problem.

Mitigating the loss of deltaic wetlands in south Louisiana is a popular concept but pointing to successful mitigation efforts is problematic. I’m not convinced that mitigating damage to wetlands on even a small scale is possible, let alone on a scale sufficient to make a ‘delta difference.’

During the past century, while Louisiana’s unleveed coastal marshes and forests were becoming wetter and disappearing beneath the Gulf of Mexico, floodplains in the nation’s watersheds were becoming dryer, as a result of draining, agricultural conversion, infilling and urban development. Loss of both coastal and interior wetland habitat was of little public concern until the 1990s, whereas dramatic publicity about water pollution after Earth Day in 1970 led to the expansion of the 1948 Water Pollution Control Act into the Clean Water Act (CWA) of 1972.

CWA Section 404

The most salient effect of the CWA relates to its incorporation of Section 404, which restricted the discharge of pollutants (especially dredge spoil and other fill material) into navigable waters. I’m intrigued that, whereas Section 404 is widely recognized as providing at least a modicum of protection for the nation’s wetlands, you won’t find the term ‘wetland‘ if you click on the above link from an official EPA website. I suspect that this reflects the cautious political strategy of strengthening the old water pollution control act by defining infill as a pollutant, rather than explicitly restricting the development of private (wetland) property.

Navigable waters include the tributaries carrying runoff from the nation’s watershed into formerly extensive wetland floodplains dominated by bottomland hardwood forests, which in 1972 were rapidly being infilled and drained and converted to row crops. One serious cost of the conversion of wetlands to agriculture has been the relentless summertime formation of Gulf hypoxia in Louisiana waters as a consequence of the replacement of nutrient absorbing wetlands by fertilizer-leaking row crops.

Despite the huge body of knowledge about the value of healthy wetlands to absorb excess nutrients and to store flood waters the Congress has never seen fit to pass legislation specifically to protect wetlands. This would be a much harder sell than protecting water quality because it would open up the bugaboo of property rights and regulatory takings. That being said, given Louisiana’s wetland loss rate and our annual bout with the corn-fed dead zone, wouldn’t it be great if our newly constituted congressional delegation had the cajones to propose an explicit wetland protection bill going far beyond what Section 404 does? Someone pinch me, I’m dreaming.

Section 404 includes the concept of jurisdictional wetlands and compensatory wetland mitigation. Mitigation basically requires a permit applicant who desires to fill in or otherwise despoil a parcel of jurisdictional wetland to compensate for the action by conserving or restoring another tract of wetlands of similar size and function, thus resulting in a theoretical condition of no net loss of wetlands.

Here’s a quote from the above link that defines federal compensatory mitigation:

The objective of the Clean Water Act (CWA) is “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” Toward achievement of this goal, the CWA prohibits the discharge of dredged or fill material into wetlands, streams, and other waters of the United States unless a permit issued by the U.S. Army Corps of Engineers (the Corps) or approved State under CWA Section 404 authorizes such a discharge. When there is a proposed discharge, all appropriate and practicable steps must first be taken to avoid and minimize impacts to aquatic resources. For unavoidable impacts, compensatory mitigation is required to replace the loss of wetland, stream, and/or other aquatic resource functions and area. The Army Corps of Engineers (or approved state authority) is responsible for determining the appropriate form and amount of compensatory mitigation required. Methods of providing compensatory mitigation include aquatic resource restoration, establishment (creation), enhancement, and, in certain circumstances, preservation.

Louisiana was authorized to assume the administration of Section 404 around 1980, when its coastal management plan and program office housed in the Department of Natural Resources (LDNR) were approved by the feds. The primary function of the Louisiana Office of Coastal Management (OCM) is to minimize the destruction of coastal wetlands within an official state coastal zone. Here’s a quote from the state DNR/OCM web site:

“The Office of Coastal Management is responsible for the maintenance and protection of the state’s coastal wetlands. The main function of the Office of Coastal Management is the regulation of uses in the Louisiana coastal zone, especially those which have a direct and significant impact on coastal waters. It is the goal of the Office of Coastal Management to protect, develop, and restore or enhance the resources of the state’s coastal zone.”

No net loss of wetlands is an oxymoron

At both federal and state levels, the ultimate goal for wetland mitigation has been to achieve a condition of “no net loss” of jurisdictional wetlands. Over the years the compensatory mitigation process and its effects have been challenged by numerous studies, so amendments are occasionally proposed to make it more effective, such as increasing the mitigation area required. Nevertheless, wetland mitigation remains highly controversial, both with property rights advocates and conservationists.

It appears to me that the proof is in the pudding. Mitigation has been required to offset permitted damage to coastal wetlands in Louisiana since the 1980s. Nevertheless, the controversial ‘levee lawsuit’ brought by the Southeast Louisiana Flood Protection Authority-East (SLFPA-E) against 97 oil and gas companies in 2013 alleges the failure of these companies to comply with the mitigation requirements of their coastal use permits, resulting in massive wetland losses and a major black eye for compensatory wetland mitigation.

Mitigation banking

Rather than issuing small piecemeal mitigation requirements for each permit applicant the concept of mitigation banking evolved as a popular means of expanding the scale and privatizing the process of compensatory wetland mitigation. A private company or organization can purchase a large tract (mitigation bank) of marginal wetlands and sell shares to multiple permittees, in exchange for taking on the responsibility of restoring the property to a functional jurisdictional wetland status, as agreed to by state and/or federal officials. The  allows the consolidation of wetland mitigation efforts into large contiguous areas. There seems to be a broad consensus among both critics and supporters that mitigation banking is the least bad alternative for reducing the loss of wetland function from permitted development but independent studies have not demonstrated that it works.

On December 28 the Advocate published an article by Amy Wold describing an effort by the America’s Wetland Foundation to encourage private investments in saving the coast. The article touts mitigation banking as a solution to fund coastal restoration. Here’s a quote:

The highest-profile private project, expected to cost about $180 million, involves a marsh creation effort on the East Orleans Land Bridge, which is spearheaded by Ecosystem Investment Partners, a firm that specializes in this kind of work. The idea is that once the work is complete, the firm can sell mitigation credits to companies seeking to offset the damage they do to other wetlands.

Mitigation banks like that one, incentives to make it easier for private landowners to do restoration work themselves and a concept for a coastal exchange are all parts of the mix in tapping private dollars to help fix the coast.

The idea of using compensatory mitigation banking as a means of raising coastal restoration funds from permittees doesn’t pass the sniff test. It’s like Lord Grantham attempting to pay his tax bill and save his family estate by selling off pieces of Downton Abbey.

I was struck by a particularly important statement by Mark Davis at a panel discussion on funding coastal restoration that was hosted in New Orleans by

“…you cannot mitigate your way back to a better coast because mitigation is premised on destruction, so if you’re destroying things and then mitigating you’re never going to get ahead. That doesn’t mean that mitigation is not vital and important but it’s not a restoration strategy.”

I rest my case.

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  1. Really informative article post.Really thank you! Really Great.

  2. It seems that those who are biased for sediment diversions compare them to Wax Lake but say they are not comparable to the Caernarvon diversion. And it seems like those who are biased agains diversions say they are comparable to Caernarvon but not Wax Lake. Is this just a contest to claim who’s bias is better? Is this a matter of deciding who’s experts are better? When scientists start competing to prove bias, how in hell can we, the public, believe science is actually guiding the process?

  3. Chris McLindon says:


    I think we hit the limit on internal replies. I think your idea of a post about Blum and Robert’s 2009 “We conclude that significant drowning is inevitable” paper is a great idea. I appreciate your efforts. A couple of comments for your consideration: they admittedly performed a very simplistic “static submergence model” with a uniform 1 meter of relative sea level rise. Relative sea level rise combines global sea level rise with local subsidence. Their 2012 examination of the relative sea level rise measured by the NOAA tidal gauge at Grand Isle shows that it is composed of roughly 20% global sea level rise and 80% subsidence.

    A very strong case can be made that subsidence is the overwhelming cause of land loss in coastal Louisiana, and that it is due primarily to faulting. The fundamental problem with the simplicity of the Blum and Roberts model is that it assumes a uniform rate of subsidence. Rates actually vary quite dramatically. Dixon’s 2006 measurement of rates over 20 mm/yr (8 inches per decade) in the Central Wetland Unit using GPS technology more than adequately explains the submergence of those wetlands and the drowning of the cypress swamps that once inhabited them. An extrapolation of that rate back in time also offers a very good explanation for the current elevation Fort Proctor in Lake Borgne, and for the depth of the 2100 year-old in-situ cypress stump that David Frazier (1967)documented in a core taken in Breton Sound. After drowning the remnants of that cypress swamp continued subsiding to a current depth of 33 feet below sea level.

    Shea Penland used the DNR interior tidal gauges in the Terrebonne/Barataria Basin to measure rates of relative sea level rise up to 23 mm/yr in his 1998 LGS study. Morton contoured the values from that study in map published in his 2002 study “Subsurface controls on historical subsidence rates and associated wetland loss in southcentral Louisiana”. This contour map can be overlain of the surface traces of the faults mapped by Roberts in his 2008 paper “Evidence for Active Growth Faulting in the Terrebonne Delta Plain” and the USGS Land Area Change map. It is plainly obvious by the combination of results from these independent studies that the rates of subsidence measured by the tidal gauges are due to the movement of the faults, and together they are the cause of the wetlands loss in this area.

    The critical importance of this revelation is that the same explanation can be applied to every other hot spot of wetlands loss on the coast. These hot spots of land loss are hot spots of subsidence due to active fault movement. The one that we should probably pay the most attention to in the short term is the hot spot at Myrtle Grove. If we can assume by association that land loss there has been caused by the same rates of subsidence that can be measured in other hot spots, then we should seriously rethink if that is where we should be spending a billion dollars on a sediment diversion. A subsidence rate of 8 inches per decade would doom the project from the outset.

    I would seem to

    • Kelly Haggar says:


      Maybe you should sit down with this Chris fellow and watch one the slide shows he has been giving all over the state for the past year? Places like levee boards and geological societies and industry groups?


      • Kelly and Chris-
        I’m happy to have sparked a discussion about the mechanics of land loss in a delta deprived of its sediment – a subject about which I am unqualified to offer decisive comment. If it’s virtually impossible to stop the loss rate the public deserves to know it.
        I envision a workshop in which Mike Blum, Harry Roberts, Tor Tornqvist, Mead Allison, Paul Kemp, Mark Kulp, Bob Morton, Ehab Meselhe, Sam Bentley, Woody Gagliano and…were charged with creating a first cut assessment of the annual sediment volume required to sustain a meaningful part of the delta plain, given current and prospective subsidence rates, faulting and sea level rise. This sediment demand would then be compared with the most optimistic assessment of sediment supply based on suspended load in the river.
        If the demand id far greater than supply the Master Plan needs to reflect that reality.
        Some one should propose this idea at the upcoming CPRA meeting, which would likely be a total waste of time.

        • Kelly Haggar says:

          First, thanks for listening. Good on you!

          Second, “mechanics of land loss in a delta deprived of its sediment”

          If sitting at the feet of numerous masters all these years has taught me anything, it’s that there can be “mechanics of land loss in a delta” whether it is “deprived of its sediment” or not. (For that matter, whether the shore is a also delta or not.)

          That further assumes the delta (or coast)in question is in a still stand. Glaciation (or de-) changes everything. If the ocean is rising (18K BP to +/- 8K BP) you can have all the sediment you want. 400 ft/130 m and the ocean’s gonna win. Flip the ocean the other way and you get 52K year old cypress logs (still with sap in them) in the sand miles off what is today the coast at Mobile.

          Third, I’d offer some personnel changes to that panel. I think that best handled offline (mainly additions).

          Finally, IMHO, there are some critically important drivers and variables which are not being taken into account.

          – vertical control. Unless and until both the taxpayers and the office holders figure out that 3/4 of the “rise” at Grand Isle is actually only the tide gauge being in a descent, we’re wasting our time and their money on the coast.

          – time. People need to get over this idea that what their PaPa showed them means anything. If we’d had a Gov in 2,500 BC, there’d have been a CPRA organized to “Save Delta #8” (or whichever Frazier one it was that year). If Frazier were writing today instead of in 1967, he’d be calling Wax Lake “Delta 17.”

          – choice/decision. There’s a reason the National Academy said we ought to choose back in 2006. The “every kid on the playground gets a popsicle” dribbling out of projects here and there needs to stop. All that does is set people up for disappointment. We have to choose, and picking anything in a hot spot is flat out stupid, period. No one – NO ONE – has enough stroke to beat Mother Nature.

          Many years ago I saw an Armstrong Labs talk on night vision goggles. First two lines on the first slide:

          – Nothing turns night into day except the sun

          – There will never be enough “right stuff” to overcome the laws of physics

          It really, REALLY matters what is actually happening to our coast, and why. Anything I can do to get the lights turned on, sign me up . . . .

          • OK folks. If there’s one thing we all seem to agree on it’s that the Master Plan is far too optimistic in tone, which misleads the public into thinking that much of what’s left of the delta plain could be saved with the investment of $50 billion.
            Let’s close the dialogue here and let me go forward with new posts that will hopefully incite more discussion.
            Thanks to all.

  4. stormineaux says:

    The state of Louisiana has never assumed the Section 404 program. That’s because under that statute, any state which assumes the program has to implement it for the entire state, not just a portion of it. However, Louisiana did legislate its own wetland mitigation requirement for Coastal Use Permits around the time that the Coastal Restoration Program was created. I heard that DNR issued new Coastal Use Permit Mitigation rules last year, and, if they are anything like the original rules, they will make for some dry reading.

    • Thanks for this comment, which reveals my misunderstanding of the fine points of Section 404 and how the federal/state effort is shared (or not). This arcane subject is not user friendly, as you imply.

      • Anonymous says:

        No, it isn’t user friendly at all. The 404 program is not even a statute, but rather a set of CFR regs adopted to “implement” a statute.

        Don’t bring up navigable waters in this context – that’s Sec 10 of the Rivers and Harbors Act of 1899. Or you could try reading SWANCC (2001) or Rapanos (2006) and see if you can follow the logic.

        Corps mitigation did not get a CFR until 2008.

        As for strengthening wetland protection via Congress, the last time Congress enacted a law affecting wetland jurisdiction was in 1990. It was a rider written by own Sen Bennett Johnston, D-La, which prevented the feds from using the 1989 common federal delineation manual. It called to much wet and the outcry was loud enough to move Congress. (The Corps eventually got the 1989 version in the back door by calling it a series of “Regional Supplements” to the 1987 wetland manual.)

        None of the bills to reverse SWANCC ever came close to passing.

        If Congress does anything at all in 2015, it will try to block to expansion of Corps jurisdiction via the rule-making currently underway. Of course it will be vetoed if it does pass so the winners in 2016 will try again in 2017.

        Finally, be very careful about wishing for “protection” of “wetlands.” If all you understand is “such as marshes, swamps, and bogs,” that’s one thing. But anyone who does not realize what “wetlands” mean under Corps manuals, Supps, and “Guidance,” well, I hope your IRA is in an FDIC bank. If it’s raw land, 30 miles from water, the life savings of several generations could be wiped out with the stroke of a pen. The assessed mitigation can easily be several times the street value of the land.

        • You and Stormineaux both allude to a bureaucratic morass associated with the regulatory (political) side of saving the coast, 80% of which is privately owned. The huge issues of limited mud and money seem less challenging in comparison.
          I agree that Bennett Johnston pandered with the best of them, calling for funds to restore the coast while seeking to weaken the limited protection of existing wetlands. David Vitter continues that proud tradition, as will Bill Cassidy, I’m sure.
          I fault the media for not alerting the public to this kind of hypocrisy and for not challenging the laughably rose colored coastal projections of Garret Graves’ successor Jerome Zeringue. The Master Plan of 2017 is just around the corner, folks. Arm yourselves in advance with a healthy cynicism quotient.

          • Anonymous says:

            I’m trying to be restrained here but you just don’t get it. Drop this crazy notion that “protection” of “wetlands” has something to do with coast. Or that there is any connection whatsoever between opposition to expansion of Corps inland jurisdiction and the coast. The two issues aren’t close enough to be apples and oranges.

            SWANCC was fought over an abandoned quarry. Nothing flowed into or out of it but rainwater. And “isolated” did not start with SWANCC in 2001. Wilson out of the 4th Cir in 1998 was earlier.

            BTW, my hunch is you have confused state assumption of 404 (so far only NJ and MI) with the PGP La has for up to 3 acres of impact within our coastal zone. The last 4 or 5 general counsels of DNR have all recommended assuming 404. All of them were turned down for the same reason – the state personnel costs would soar.

            The only advantage I can see to state assumption is that state employees listen to state senators whereas federal employees don’t even air off US Senators.

            • Anonymous-
              I don’t want to quibble over defining jurisdictional wetlands or whether the feds or the state should have the authority to issue coastal use permits. This post was intended to challenge the notion that mitigation as currently practiced has slowed the rate of coastal landloss.
              The hypocrisy and hollowness of the coastal use permitting process was demonstrated recently when DNR (apparently with the blessing of the CPRA) agreed to allow the construction of a coal shipping facility (the RAM project) adjacent to the site of what should be the flagship sediment diversion project at Myrtle Grove. Both Jerome Zeringue and Secretary Stephen Schutz should be called to task for this incredibly shortsighted decision (which has thankfully been put on hold by a judge).
              ‘Coastal management’ has become a euphemism for a program that rationalizes prioritizing commerce over conservation.

              • Anonymous says:

                “to challenge the notion that mitigation as currently practiced has slowed the rate of coastal land loss.”

                Now you’re 100% correct. It has not and it won’t. Not in the places La and the Corps keep approving.

                As to the planned diversion (river cut or slurry piped) near the coal site, then the real question is whether either one will work there. And the answer is “No, neither will.”

                Check out Garland Robinette’s show from this past Wed. Eye opening!

                1-7 10am Garland, Louisiana Coastline

                Garland talks to Save Louisiana Coalition President George Ricks, Geologist Chr…

                Mentioned: chris paul, new orleans, interest rate, woods hole


                On your other question, considering “commerce” or “conservation,” the United States made its choice a LONG time ago. Think back to the 1897 National Geographic article Tommy Sands gave you several years back.

                Unless Panamax changes to value of New Orleans as a port, the winner will always be “commerce.”

                • Anonymous-
                  I appreciate your posting the link to the podcast of a recent Garland Robinette show on coastal issues, in which his three guests, who represent the Save Louisiana Coalition, are heavily biased.against sediment diversions. The first guest, Captain Ricks, has no technical background whatsoever. The second, Cathy Hagar has some geological credentials, as does Chris McLindon but Cathy’s statement that land loss in Louisiana is primarily the result of faulting would be strongly debated by the majority of delta experts. Likewise, Chris’ statement that the land loss of marshes in Breton Sound during Hurricane Katrina was primarily the result of nutrient loading by the Caernarvon diversion he’s been influenced solely by the long term anti-diversion opinion of Gene Turner, who’s views on this subject have been discredited by many experts, including Jim Morris at USC.
                  The Caernarvon river water diversion bears no resemblance to the multiple massive sediment diversion projects that most scientists advocate.Due to the limiting factors of mud, money and political muscle I share Chris’ pessimism on our ability to fix the delta but to spend all the coastal money on protection alone, as advocated by Ricks, would be pure folly.

                  • Anonymous says:

                    See what your team of experts has to say about this paper. And, if it’s wrong about faulting explaining Goose Point, what does explain it?


                  • Chris McLindon says:


                    the delta experts that have published on the significance of faulting as a factor in land loss include Woody Gagliano (CEI),Harry Roberts(LSU Coastal Studies), John Lopez(Lake Pont Basin Foud.),Roy Dokka(LSU), Mark Kulp(UNO), Robert Morton(USGS) Kyle Straub (Tulane), not to mention Harold Fisk, the godfather of coastal geology. I would be interested to hear the list of the “majority of coastal experts” that do not recognize faulting as a primary factor in wetlands loss.

                    • Chris-
                      I said that experts would not agree that faulting is THE primary cause of land loss, not A cause. No one denies that faulting is important but the primary cause of the delta decline is a massive sediment deficit, as exemplified in the critical paper by Mike Blum and Harry Roberts in 2009. I’m working on a post on that subject.

                    • A few science issues for your consideration in that pending Blum & Roberts 2009 post. (BTW, a legitimate take on their 2012 paper is they walked back their grim conclusion of 2009.)

                      First, ask your contacts to go over that Goose Point paper the law prof posted. That paper doesn’t just claim faulting, aided by crustal deformation, is the largest cause of land loss there, it says it’s pretty much the only cause of loss there. Is she right? If not, what is?

                      Second, don’t forget Andrew W. Tweel and the dreaded, ever lurking R. Eugene Turner, “Watershed land use and river engineering drive wetland formation and loss in the Mississippi River birdfoot delta,” Limnol. Oceanogr., 57(1), 2012, 18-28. Save copies of their Figures 2 and 6 so you can open them later in whatever image editing program your IT pals prefer.

                      Third, stop by That’s a web page from the St. Petersburg Coastal and Marine Science Center of the USGS. Even though he’s retired now, they are still pushing Morton’s “pressure depletion did it.”

                      Scroll down their “Subsidence and Wetland Loss Related to Fluid Energy Production, Gulf Coast Basin; Induced Subsidence Related to Hydrocarbon Production” page until you can save the “larger version” of

                      Once you have all three figures saved, open them in some program you or your IT folks can edit and sync them up horizontally to the same time scale.

                      Does the “pressure depletion” thesis still seem valid? (If you run into too much trouble making such an exhibit sync up correctly I already have made it so I know what it shows.)

                      If I may play off Gandhi’s response upon being asked what he thought of Christianity, “I think science is a great idea. When are we going to start seeing some of it?”

                      As in, First

                      “Do we know with meaningful confidence why the coast is changing?”


                      “Have we failed to properly account for the tectonic-geological drivers?”

                      If the “we” in either question means the coastal scientists who have been ruling the CWPPRA and CPRA roosts over the last 20 years, I submit the answer is “No” to both questions.

    • stormineaux says:

      One other aspect of compensatory wetland mitigation, as it applies to the Louisiana coast, is its relationship to the state’s match on CWPPRA projects. The state has a federally approved Coastal Wetlands Conservation Program, which contains a requirement that Coastal Use Permits must ensure that there be no net loss of wetlands as a result of permitted activities. This basically means that any Coastal Use Permit that involves alteration of wetlands has to also require compensatory mitigation (there are some exceptions). This has reduced the state’s CWPPRA match share from 25% to 15%. It should be noted that the Coastal Conservation Plan is basically a memorandum of understanding – not a law or regulation.

      By the way, when discussing Louisiana environmental issues, in my opinion “Game of Thrones” analogies are more apt than “Downton Abbey” ones.

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