waves and storm surges that reach our levee system,” says colonel richard p. wagenaar of the u.s....

www.lacoast.gov

March 2006 Number 30

Please address all questions, comments,suggestions and changes of address to:

Gabrielle Boudreaux BodinWaterMarks Co-editorUSGS National Wetlands Research Center700 Cajundome Blvd.Lafayette, LA 70506(337) 266-8623

E-mail: [email protected]

WaterMarks is published threetimes a year by the LouisianaCoastal Wetlands Conservationand Restoration Task Force tocommunicate news and issues ofinterest related to the CoastalWetlands Planning, Protectionand Restoration Act of 1990.This legislation funds wetlandsrestoration and enhancementprojects nationwide, designatingapproximately $60 millionannually for work in Louisiana.The state contributes 15 percentof total project costs.

For more information about Louisiana’s coastal wetlands and theefforts planned and under way to ensure their survival, checkout these sites on the World Wide Web:

www.lacoast.gov www.saveLAwetlands.orgwww.btnep.org www.crcl.orgwww.lca.gov

ABOUT THIS ISSUE’S COVER . . .Once a tranquil vista of marsh grass stretching tothe horizon, this segment of Louisiana’s coastalwetlands shows the damage wrought byhurricanes Katrina and Rita in the autumn of 2005.Although debilitated by the storms, wetlands arecredited with reducing damage further inland byabsorbing wave action and decreasing the heightof storm surge. Scientists are monitoring theravaged marshes to gauge their resiliency andestimate the length of time they take to recover.

Photo credit:Louisiana Department of Natural Resources

SubscribeTo receive WaterMarks, e-mail [email protected]

For current meetings, events, and other newsconcerning Louisiana’s coastal wetlands, subscribe to

the Breaux Act Newsflash, our e-mail newsletter, at

www.lacoast.gov/newsletter.htm

March 2006 Number 30

WATERMARKSLouisiana Coastal Wetlands Planning, Protection and Restoration News

3 Hurricanes Prove the Urgencyof Rebuilding Wetlands

5 Coastal Landscape BattlesWeather to Protect Mainland

7 Scientists Take the Pulseof a Pummeled Coast

11 Breaux Act Projects Stand Upto Hurricanes’ Punishment

14 WaterMarks Interview withRobert A. Dalrymple

Photo CreditsInterior page thumbnail credits: U.S. Army Corps of Engineers; Louisiana Sea Grant College Program; U.S. Geological Survey;Louisiana Department of Natural Resources; Louisiana Department of Tourism

WATERMARKS March 2006 Number 30

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xposing the vulner-ability of the fragilecoastal environment,

the storms also highlightedthe wetlands’ economicimportance: When damage

Hurricanes Prove the Urgencyof Rebuilding Wetlands

caused by Katrina and Ritashut down 90 percent ofcrude oil production in theGulf of Mexico, gasolineprices soared nationwide.

“A fifth of the U.S. crude

oil supply passes throughLouisiana’s wetlands, whichshield pipelines, platformsand other infrastructurefrom hurricanes,” says RexCaffey, director of theLouisiana State University(LSU) Agricultural Center’sCenter for NaturalResource Economicsand Policy.

In 2005, hurricanes Katrina and Rita dealt catastrophicblows to coastal Louisiana communities, proving thenecessity of better hurricane protection.

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Storms Reveal High Cost of Marsh Loss

Some 25 percent of U.S. fisheries production comes from Louisiana’s wetlands, but after the 2005 hurricane season,says Rex Caffey of the LSU AgCenter, “It’s possible that many fishing companies, particularly small operations, willnever recover. We really don’t know what Louisiana’s fishing industry is going to look like after Katrina and Rita.”

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Cows crowd the porch of a Louisiana house, seeking to escape the risingwater. Hurricanes Katrina and Rita flooded pastures across southern Louisi-ana, killing thousands of cattle and causing nearly $46 million in livestockand property losses to Louisiana’s cattle and dairy industries.

“It’s impossible to saywhat might have happenedif we had already rebuiltLouisiana’s wetlands by thetime Katrina hit, but thenet loss of 1.2 million acresof coastal wetlands over thelast century has definitelyincreased the vulnerabilityand exposure of the state’scoastal infrastructure, andthus its economy.”

Restoration Essential toCoast’s SurvivalWhile the impact ofKatrina and Rita on thepetroleum industry was feltalmost immediately, thestorms’ effects on otherindustries such as fishingand agriculture might notbe known for years.

The hurricanes’ highwinds and flood waterswiped out crops and dam-aged timber in south Loui-siana; saltwater intrusionmay have rendered someland unsuitable for farming.Both storms caused exten-sive damage to the state’scommercial and recre-ational fishing industries,destroying boats, marinas,equipment and processingfacilities and ravagingthe marshes and barrierislands that provide habitatfor oysters, shrimp, fish andother aquatic species.

“Our state’s future de-pends on creating a systemthat treats coastal restora-tion and hurricane protec-tion structures as equals,”says Scott Angelle, Secre-

tary, Louisiana Departmentof Natural Resources. “Itcan’t be one or the other —we need both.”

As scientists and policymakers seek ways to pro-tect coastal communitiesand industries from futurehurricanes, they look to themarshes and barrier is-lands that form the coast’sfirst line of hurricanedefense.

“We’ve known for manyyears that vegetated

wetlands reduce the tides,waves and storm surgesthat reach our leveesystem,” says ColonelRichard P. Wagenaar ofthe U.S. Army Corps ofEngineers and Chairman ofthe Breaux Act Task Force.“Hurricanes Katrina andRita left no doubt thatcoastal wetland restorationmust be a central compo-nent of any hurricaneprotection plan.”

Hurricanes Deal Heavy Blow to Louisiana Economy

INDUSTRY ESTIMATED LOSS of REVENUE

Forestry $839,933,224.00Agronomic Crops $357,854,629.00Fruits/Nuts/Vegetables/Honey $41,951,686.00Livestock and Forage $75,580,644.00Aquaculture $58,330,115.00Fisheries $176,280,625.00Wildlife/Recreational $40,803,977.00

Total Estimated Revenue Loss $1,590,734,900.00

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Coastal Landscape BattlesWeather to Protect Mainland

aking on the mightand fury of thesestorms are the

state’s barrier islands andcoastal wetlands — a frag-

ile, yet proven, line ofdefense.

“Barrier islands andmarshes can’t stop the fullforce of a category 4 or 5

hurricane,”says JackKindinger,associatedirector ofthe UnitedStatesGeologicalSurvey(USGS)FloridaIntegratedScience Center. “But be-cause these natural buffersreduce the effects of dailywave action and winterstorms on shorelines andlevees, a coast protected bywetlands will fare better ina storm of any size.”

Marshes Soak Up SurgeAs a hurricane movesinland, coastal marshesdeprive it of the warmmoisture that fuels thestorm’s growth. Wetlandsalso diminish a hurricane’sdestructive power by re-ducing storm surge andabsorbing wave energy.

“Well-vegetated wetlandsabsorb much of the surge ofcategory 1 and 2 stormsbecause of their elevationand the friction the grassprovides,” says Kindinger.Against the strength andsurge of category 4 and 5storms, he says, wetlandshave a more limited effect.

TLouisiana’s coastline has been a top pick over the lastcentury for major hurricanes making landfall.

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The most powerful storm ever observed in the Gulf of Mexico, Hurricane Ritamade landfall near Louisiana’s western border September 24, 2005. The hugeweather system pushed high winds and drenching rains northward acrossstates from Texas to Florida.

Can a stalk of grass resist hurricaneforces? Multiplied over hundredsof acres, wetland vegetationdoes moderate storm surge aswell as wind and wave energy.

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How much protection dowetlands offer? Manyvariables determine howwell marshes reduce stormsurge, including the slopeof the continental shelf andthe speed and direction ofstorm winds. Studiessuggest that it takes aslittle as one mile or asmany as four miles offunctioning wetlands toreduce storm surge bya foot.

Throughout the year,wetlands protect leveesfrom the erosive effects ofwaves by reducing theirheight and intensity. “Alevee protected by marshwill require much lessmaintenance than will alevee exposed to dailytides and waves,”Kindinger says.

Storms Stumble OverSandy Speed BumpsDelicate ribbons of marshand sand, barrier islandsseem too small and fragileto have any effect on apowerful hurricane hun-dreds of miles across. Butthe severe damage theseislands endure — oftenlosing as much as half theirland area — is proof oftheir effectiveness.

“It takes a lot of force toremove that much sedi-ment,” says Greg Stone,James P. Morgan Professorat Louisiana StateUniversity’s Coastal Stud-ies Institute and Depart-

Many factors determine how well barrierislands stand up to hurricanes, includingstorm size and strength and the islands’shape and elevation. Wide, moderately tallislands, such as those along the Floridacoast, tend to fare well, says LSU’s GregStone.

“The sand transported from an island’sbeach and dunes by storm surge needssomeplace to go, and a wide island offers a

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The Bigger the Bump, the Better the Barrierplatform for holding that sand,” Stone says.“Because Louisiana’s barrier islands aretypically low and narrow, sediment tends tobe pushed over the islands and into thebays behind them.”

If that sediment isn’t replaced, the islandwill eventually disappear, as is happening tomany Louisiana barrier islands. The followingillustrations show the different effects ofstorm surge on barrier island sediment.

Impact Level 1: Storm wavesreach no higher than the beach.The beach will erode, but overtime normal wave action willreturn the sand to the island.Sand remains within the system.

Impact Level 2: Waves reachhigher than the base of thedune. The island’s beaches anddunes will erode and retreat,perhaps permanently.

Impact Level 4: If the storm surgeis high and the elevation of thebarrier island is low, the island canbecome completely inundated.Sand is removed and transportedover the island into the baybehind it.

Impact Level 3: Waves overtopthe barrier island. If waves reachover the dune, or if there is nodune, sand will be pushedlandward. Over time, the islandwill migrate toward land.

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ment of Oceanography.“That’s energy depletedfrom the storm’s surge andthe wind-driven waves ontop of it. Think of a barrierisland as a ‘speed bump’that dissipates hurricane-generated power.”

Barrier islands, particu-larly those close to themainland, also protectcoastal marshes.

“Where barrier islandshave weakened or disap-

peared, bays are exposed tohigher wave energy, whichaccelerates wetland lossand makes the coast evenmore vulnerable,” saysStone. “Putting money intorebuilding and fortifyinglevees and improving floodprotection is vital, but itmust be done in conjunctionwith the restoration ofbarrier islands and thewetlands that liebehind them.”


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Scientists Take the Pulseof a Pummeled Coast

s Katrina and Rita swept over southern

Louisiana, they lefttheir imprint on the land-scape. Using data collectedto assess the storms’effects, scientists areredrawing maps, refininghurricane modeling andimproving techniques ofcoastal restoration.

From Big Pictureto Fine DetailFollowing Katrina and Rita,John Barras, a scientistwith the USGS NationalWetlands Research Center,has been mapping changesin Louisiana’s coastalwetlands. In some areas,vegetation was torn fromits roots to expose a muddymarsh floor. In other placesthe marsh soil and plantswere ripped apart andpushed aside, allowing newbodies of open water toform. “Satellite imagesmake the breaks in themarshes look like one bigpond,” Barras says, “butwhen you get closer tothem, you can tell there area few very large areas —areas over 500 acres — but

most of the damage to thewetlands is from many,many smaller tears, ripsand shears in the marsh.”

Barras estimates thedeepest of the new openwater areas to be threefeet; most are probablyabout six inches deep. Thesmaller the areaof tear or shear,the more likelythe marsh is torecover. Largerexpanses ofdamage, such asin Upper BretonSound or inWhite’s Kitchen, willprobably become perma-nent lakes.

Barras makes hisdetermination of landscapechanges by comparingsatellite images takenbefore and after the storms.Classifying different colorsin an image as land orwater, Barras looksfor new occurrencesof water in post-stormphotos. “Some areasare so large they areeasy to find from theground,” says Barras,“but you need an

Marsh vegetation brown from salt burn. Wetlands shorn ofgrasses, exposing mud flats pitted with puddles. Treesdangling bands of twisted metal, plastic bags and bits ofcloth from branches stripped of leaves.

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From Satellite Imagery to Soil Samples

Words That PictureMarsh Damage

Scientists in the field often describethe effects of storms on the wetlandswith colorful terms. Here’s a glossaryof their lingo.

Rolled: strips ofmarsh mat up-rooted and rolled upjelly-roll fashion

Shear: a ripbetween marshsurfaces that tearsmarsh and moves it

apart, allowing expansesof water to form

Compressed or folded:marsh mat blown intoridges resembling anaccordion or, in moreaqueous marshes, acrumpled bed sheet.

Scoured: marshwith vegetationripped off at theroots, exposing amuddy bottom

Inverted orflipped: unbrokenmarsh mat liftedfrom its clay base and overturned withroots pointing skyward

Marsh balls:marsh mud andgrass pushedtogether intocinderblock- tosofa-sized clumpsand blown aboutlike tumbleweed

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aerial view to appreciatethe extent of the changesthat have occurred.”Fly-overs in small aircraftand field verification ofconditions on the ground

provide more detail aboutspecific sites.

Preparing for Future StormsBased on data gatheredfrom past storms, hurricane

modeling predicts thebehavior and consequencesof future storms. Assess-ments of Katrina and Ritawill help refine modeling,to show when and where

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Satellite Image Shows Prior Conditions

This satellite image shows the condition of White Kitchen, Louisiana, southeast of Slidell, in November 2004.


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the fastest winds andheaviest rains are mostlikely to occur. The assess-ments contribute to publicsafety by increasing theveracity of weather fore-

casts, giving prudent warn-ing to people in harm’s waywhile reducing the disrup-tion and costs of unneces-sary evacuations.

Assessments also influ-

ence coastal restorationefforts. By analyzing theperformance of variousprojects during and afterthe storms, scientists andengineers can fine-tune

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Post-hurricane Image Reveals Landscape Changes

This image taken in October 2005 shows submersion of marsh land masses; new shears, or areas of broken marshconverting to open water, near the West Pearl River; and loss of vegetative cover throughout the vicinity.


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It was in the midst of thesongbird migration seasonwhen hurricanes Katrinaand Rita hit the Louisianacoast. Typically these birdsfatten up for the long flightto Central and SouthAmerica in the Pearl River

Storms Disrupt Avian Itineraries

Stripping plants of certain insects, hurricane windsimmediately robbed migrating birds of a critical foodsource. In the long term, however, the storms couldcause a dramatic swelling in insect populations, as thedecay of toppled trees increases their food supply.Ecologists will watch to see if exotic species of flora andfauna invade storm-damaged areas, further threateningthe health and survival of Louisiana’s coast.

bottomlands, according toWylie Barrow, wildlifescientist at the USGSNational WetlandsResearch Center. After thehurricanes stripped plantsof leaves, fruit and insectsin the fertile reaches

adjoining theriver, radar track-ing indicated anincreased numberof birds staging fortheir trip in thepiney woods to thenorthwest. “Notonly does thislengthen theirjourney by 15 to 30miles,” says Bar-row, “but food inthe piney woods isnot as rich or asabundant as in thebottomlands,making it harderfor the birds tofatten up.”

techniques to increase theirendurance or boost theirprotective capacity. Forinstance, observation ofwhich plants best with-stood high winds, or howthe electronic componentsof water control structuresfared in a storm surge, willaffect future decisions andfactor in evaluations of aproject’s cost effectiveness.

An Uncertain PrognosisWithin weeks of the hurri-canes, the environmentshowed signs of recovery.

Trees budded with unsea-sonable new growth, andsprigs of vegetation showedgreen in scoured areas ofthe delta.

But the lasting effects ofthe hurricanes are difficultto predict. How much of theestimated hundred squaremiles of lost land willremain open water? Willthe freshwater marshesthat were drenched withsalt water turn brackish orconvert to open water? Willfisheries dependent on thewetlands for food and

habitat rebound? And howmuch of the wetlands’protective capacity remainsas a new hurricane seasonapproaches?

“It’s impossible to tell theextent of damage yet,”Barras says. “It may take ayear, two years, to deter-mine what changes arepermanent. Scientists willcontinue to monitor andevaluate Louisiana’s coastto answer these questionsand many more.”

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Like other Louisianacoastal wildlife, songbirdssuch as the Northern Parulawarbler shown below wereseverely affected by thehurricanes. Just as it willtake time to gauge many ofthe storms’ consequences, itwill take time to fathomtheir full toll on thesongbird popluation.

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Breaux Act Projects Stand Upto Hurricanes’ Punishment

he storm’s 120 mphwinds and 15-footstorm surge wiped

out subdivisions and campsalong the shore, leavingbehind only streets and theconcrete slabs of buildings.

But nearby, a Breaux Actbeach restoration projectsustained only minor dam-age despite taking an evenmore direct hit from stormwinds and waves.

Similar results werefound across coastal Louisi-ana: Breaux Act wetlandrestoration and protectionprojects emerged fromhurricanes Katrina andRita largely unscathed.

“Out of 107 projects, onlyfour or five experiencedserious damage fromKatrina and Rita — about$15 million in damage to$475 million worth ofprojects,” says GarrettBroussard, senior operationand maintenance engineerwith the Louisiana Depart-ment of Natural Resources(DNR). The storms sweptsediment off barrier islandsand uprooted vegetation,but in most instances,Broussard notes, the mate-rials used to create earthenterraces, rebuild beaches

Hurricane Rita made landfall near the west Louisianatown of Holly Beach on September 24, 2005.

Few Sites Suffer Damage

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The Cameron Parishcommunity of Holly Beach,near the junction of Hwy27 and Hwy 82, beforeHurricane Rita.

Hurricane Rita’s 20-footsurge demolished thetown and inundatedthe marsh.

A Breaux Act project that hadadded 1.7 million cubic yardsof sand to the shorelinehelped protect the fragilemarshland north of Hwy 82and west of Holly Beach. “It’shard to say what long-termeffects the slug of salinity fromthe surge will have on themarsh,” says David Burkholderof the Louisiana Departmentof Natural Resources. “But theproject held its ground,which gives the wetlands afighting chance.”


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and shield shorelinesremained in place.

“That’s an excellentoutcome given the size andintensity of these storms,”he says. “It shows how wellthe science behind coastalrestoration plays out on theground.”

Shoreline Project SurvivesAmid DevastationThe Holly Beach SandManagement project wasdesigned to protect 8,000acres of marsh. Sand wasdeposited along the shore-line behind existing rockbreakwaters, then held inplace using vegetativeplantings and two or three

rows of sand fencing.“Rita destroyed the

fencing and swept somesand across the highwayand into the marsh,” saysDavid Burkholder, anengineer manager with theLouisiana Department ofNatural Resources. But thefencing, installed in 2003during the project’s con-struction, had created high,stable dunes, so altogetherthe beach lost little sand.

With the beach intact,the marsh is still protectedfrom the long-term effectsof salinity, and the projectis still doing what it wasdesigned to do. “The fenceswere a big factor in pre-venting more extensivedamage and marsh loss,”

Burkholder says. “We’lltake that lesson with us tofuture projects.”

Floodwaters a Boon toLand-Building TerracesThe 2005 hurricane seasonmay have caused as muchas 10 years’ worth of landloss in less than a month asit flooded marshes anderoded barrier islands. But

at LittleVermilion Bay,located insouthernLouisiana’sVermilionParish, hurri-cane floodingactually cre-ated new land.Completed in

1999, the Little VermilionBay Sediment Trappingproject built 19,700 feet ofearthen terraces to reducewave energy and trapsediment. “We designedthis project to mimic thefunctioning of a river delta— to collect sedimentbetween thin fingers ofland,” says project managerJohn Foret of the NationalMarine Fisheries Service.

Following Hurricane Liliin 2002, scientists discov-ered that as the stormsurge receded from the bay,it left behind a thick layerof sediment on the baybottom between the ter-races. This experience wasrepeated with HurricaneRita, says Foret, who vis-

Above: Hurricane Rita inundated theterraces at Little Vermilion Bay, delivering apotentially damaging dose of saltwater tomarsh plants. “But because the saltwaterreceded quickly, we expect a full recovery,”says John Foret of the National MarineFisheries Service.

Right: Foret says the only significant damageto the terraces was caused by this oilfieldbarge, torn free from its moorings andpushed onto a terrace by storm surge.

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ited the site by boat amonth after Rita madelandfall.

“Under normal circum-stances this project trapssediment very well,” Foretsays. “The additional sedi-ment accretion duringstorms accelerates themarsh building process.”

That increases the resto-ration value of the projectover time, Foret says. “Thisproject has now survivedthree winters and twomajor hurricanes, and it hasnot only endured but hasexceeded expectations forbuilding a foundation formarsh plants to colonize.That confirms the validityof the science behind itsdesign. We can build thesekinds of projects withconfidence that they’llperform well.”

Island Losses SupplyValuable InformationAs the coast’s first line ofdefense against hurricanes,barrier islands like EastIsland endure the full forceof these storms, sufferingsevere erosion as theyabsorb wind, waves andstorm surge.

Funded through theBreaux Act, the IslesDernieres Restoration EastIsland project restored theisland in 1999. But ashurricanes Katrina andRita tore through its eastend, East Island lost almosta third of its land mass.

“About 2,000 feet of theisland is gone,” says DarinLee of the Louisiana De-partment of Natural Re-sources. But the destruc-tion offers important infor-mation to scientists whodesign barrier island resto-

ration projects.“The ends of these is-

lands typically take more ofa beating than other areasas water rises and scoursaround them,” Lee says.“With each storm, wegather more data regardingthe optimal combination ofelevation, sand placement,fencing, plantings and otherelements.”

“Coastal engineeringisn’t an exact science,”explains Burkholder. “Butsurveys of project sitesafter major storms give usan opportunity to fine-tunethe science behind buildingwetlands. We call thatprocess ‘adaptive manage-ment’ — evaluating projectsand incorporating newinformation into our de-signs. We’re constantlylearning how to make theseprojects perform better.”

Hurricanes Katrina and Rita carved a four-foot-deep channel through East Island, part of the Isles Dernieres chain inTerrebonne Parish. “This breach lets higher wave energy into the bay behind the island, which will impact thewetlands that East Island protects,” says Darin Lee of the Louisiana Department of Natural Resources.

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WATERMARKS Interview withRobert A. Dalrymple

WATERMARKS: We’ve heard a lotabout the failure of NewOrleans’ flood walls andlevees after Katrina. Fromyour perspective as anengineer, what went wrong?

Dalrymple: We understandthe general principles ofthe failure but we don’t yetknow the specifics. Forexample, we know thatfactors such as the composi-tion of the soil beneath thelevees and the scouringeffect that overtoppingwaves have on the leveescaused problems. We alsoknow that the overallstrategy to protect NewOrleans was sound.

WATERMARKS: Does that meanthat it may not be necessaryto increase the protectionlevel of the levees?

Dalrymple: The presentlevees are designed towithstand a category 3hurricane. Another cat-

egory 4 storm hitting thecity will overtop the levees.When levees are designedand constructed correctly,you’ll see flooding in thestreets only for a matter ofhours, not days. The leveeswould hold and the damagefrom floodwaters could beminimized.

WATERMARKS: So why all thediscussion about the needto increase the level ofprotection?

Dalrymple: There is thepossibility of a storm stron-ger than Katrina. Althougha category 5 hurricane isperhaps a 500-year event,no one knows when itmight occur. The Nether-lands has built levees toprotect itself from a 10,000-year event. But the decisionabout the level of protec-tion in southern Louisianaisn’t an engineering deci-sion, it’s a political decision:Is the nation willing to

Engineer, educator and author of numerous publications,Dr. Robert A. Dalrymple is the Willard and LillianHackerman Professor of Civil Engineering at JohnsHopkins University. On behalf of the American Society ofCivil Engineers, Dalrymple participated on the NewOrleans levee assessment teams that gathered informa-tion on the levees’ performance in the wake of HurricaneKatrina. Dalrymple presented his team’s findings to theU.S. House of Representatives’ Subcommittee on WaterResources and Environment in October 2005. In thisWaterMarks interview, Dalrymple talks about the lessonswe can learn from Katrina.

invest the necessary fundsto protect Louisiana’scoastal wetlands and com-munities to withstand acategory 5 storm?

WATERMARKS: The Corps ofEngineers is restoring thelevee system to a category 3level of protection. Will thathappen before the nexthurricane season starts onJune 1?

Dalrymple: The breacheshave already been repairedin the city proper, and byJune the major part of thecity’s protective system willbe back to pre-Katrinalevels. What won’t be re-paired is the damage to thebarrier islands and coastalwetlands.

WATERMARKS: Just how impor-tant are Louisiana’s barrierislands and coastal wetlandsto storm protection?


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Dalrymple: There’s noquestion that these buffersare the first line of defenseagainst a storm. It’s esti-mated that every mile ortwo of wetlands reducesstorm surge by about a foot.So when we talk aboutcreating protection equalto conditions beforeKatrina, we must includewetland and barrierisland restoration.

WATERMARKS: And the dollarsthat restoration requires?

Dalrymple: It will take asignificant financial invest-ment. But it doesn’t makemuch sense to put moneyinto rebuilding levees if wehaven’t put money intorestoring our naturalbuffers on the coast.

WATERMARKS: In your testimonybefore the House Subcom-

mittee on Natural Resourcesand Environment in Octoberof 2005, you said that wemust come to “the painfulrealization that some areas ofthe coast should not berebuilt or inhabited again.”Were you referring to NewOrleans?

Dalrymple: No. Unlikeother parts of southernLouisiana, New Orleansalready has a network oflevees and floodwalls inplace. But the reality isthat the combination of sea-level rise and subsidingland makes protectingsome areas of southernLouisiana very expensive— the magnitude of damagefrom storms is going toincrease, not decrease. Wehave to limit the loss of lifeand property, and thatmeans making politicallydifficult decisions.

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WATERMARKS: What do we needto focus on in our efforts torestore the coast?

Dalrymple: It’s been talkedabout often, but it’s worthemphasizing. We have totake maximum advantageof the sediment carried inthe Mississippi River.Sediment — from the riveror from dredging — is aprimary resource forcoastal restoration. Wecan’t afford to lose it byallowing it to drop off thecontinental shelf.

WATERMARKS: Is there anythingpositive to look at in theaftermath of Katrina?

Dalrymple: Katrina was aterrible disaster, but itbrought the crisis in south-ern Louisiana to thenation’s attention. Thiscountry has begun to under-stand the connection be-tween the destruction andthe loss of coastal wetlandsand barrier islands. We’veseen that a hurricane insouthern Louisiana canthreaten the nation’s oilsupply, and we’ve experi-enced first-hand what thatdoes to our pocketbooks —gas at three dollars a gallongets our attention. It justmay be that because of thiscrisis, southern Louisianawill get the federal fundingit needs to address theterrible loss of wetlandsthat’s occurred in recentyears — and that would bethe silver lining in a verydark cloud.

In the aftermath of Hurricane Katrina, any boat promising rescue was awelcome sight in the flooded city. Using improvised paddles, these two menwere among the many who responded to the crisis by locating stranded NewOrleanians and carrying them to safety.

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Permit No. 80

DEPARTMENT OF THE ARMYNEW ORLEANS DISTRICT, CORPS OF ENGINEERSP.O. BOX 60267NEW ORLEANS, LOUISIANA 70160-0267

OFFICIAL BUSINESS

hen Katrina’svictims couldnot be located

because floodwaters sweptaway New Orleans streetsigns, a CWPPRA partnertransformed addresses offrantic 911 callers intogeospatial coordinates andplotted them on maps forrescuers.

Faced with oil spills,burning debris and rottinganimal carcasses,CWPPRA partners re-sponded with expertise incontaining and disposingof environmental hazards.

When the needs ofdisplaced residentsoutstripped availableresources, CWPPRApartners contributed food,water, housing and otheressentials; and collecteddonations and supplies forschool districts affected bythe storms.

WATERMARKSLouisiana Coastal Wetlands Planning, Protection and Restoration News March 2006 Number 30

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And in the aftermath ofthe 2005 hurricane season,the work continues. In addi-tion to addressing environ-mental conditions in thewetlands, personnel fromCWPPRA agencies — manythemselves New Orleansresidents displaced by the

storms — have coordinatedcleanup, evaluated healthhazards, and workedaround the clock to restorenormalcy and improvehurricane protection acrosscoastal Louisiana.

CWPPRA Partners Assist inHurricane Rescue and Recovery

Volunteers from CWPPRA agencies rescued some 600 New Orleans residents fromflooded homes, attics and rooftops, and helped 2,000 more off boats and helicop-ters. Every stage of rescue, recovery and rebuilding has involved CWPPRA partners.

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waves and storm surges that reach our levee system,” says colonel richard p. wagenaar of the u.s....

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