wetland health report card - DNREC Alpha · This report card uses current research to present the...

The wetlands of the Inland Bays help supply clean water and protect property from flooding and coastal erosion. They also sustain diverse wildlife populations. But, due to activities that have filled and altered these wetlands, these services have been reduced. This report card uses current research to present the health of wetlands in the Inland Bays Watershed.

why are wetlands important?• Aone-acrewetlandcanholdupto1million

gallonsofwater.Wetlandprotectionandpropermanagementequalslessflooddamage.

• Wetlandscanremovepollutantsbeforetheyenterourdrinkingwater,streams,andbays.Vegetatedbuffersaroundwetlandsenhancethisfeature.

• Wetlandscontributefilteredwatertodrinkingwatersupplies.

• Wetlandspreventerosionofuplands,keepingpropertysafeandsedimentsoutofthewater.

• Wetlandsprovidehabitatforrareplantsandanimals.Theyarealsocriticalnestingareasformanybirds,andnurseryhabitatessentialtosustainfishandshellfishspecies.

• Wetlandscanstorelargeamountsofcarbon.Whenwetlandsaredegraded,greenhousegasesarereleasedintotheatmosphere.

changes in wetland acreageTheInlandBayswatershedhaslostapproximately60%ofitswetlandresourcessinceEuropeansettlement.Nearlyalllostwerefreshwater/nontidalwetlands.Ananalysisconductedonlossoccurringbetweentheearly1980’sand1990’sshowedthatmostofthemodernnontidallosswasduetotheconversionofwetlandstodevelopment,farmfields,andpondconstruction.Saltmarsh/tidalwetlandslosswasdueprimarilytoresidentialdevelopment,excavationandimpoundments.Anewstudyofwetlandacreagechangesduringthepast15yearswillbeavailablesoon.

Currentlywetlandsrepresent16%*ofthewatershed.ForwetlandstocontinuetoprovidevaluableservicestothecitizensofDelaware,additionallossmustbereducedasmuchaspossible.Manyoftheremainingwetlandscanbemanagedbettertoimprovethe

servicestheyprovide.Theresearchpresentedherewillbeusedtodevelopavoluntarywetlandrestorationandmanagementplanforthewatershedandinformlanduseplanningthatcouldimpactwetlands.

The bays’ beautiful backdrop is the saltmarsh, which support recreation and estuary life, like this nesting osprey.

* This percentage is based onthe 2007 Land Use Land Covermapping effort.

Read on to learn about the health of the remaining wetlands and what can be done to improve and protect them.

wetland health report cardwetland health report cardCENTER FOR THE INLAND BAYS STATE OF THE BAYS REPORT SERIES 2009-2010

Riverinewetlandsoccurnexttonaturalstreamsandprovidestorageforfloodwatersandgroundwater.Thewaterthatmovesintothesewetlandsiscleansedbeforeitmovesdownstream.Thesewetlandsalsoabsorbwatertoreducedownstreamflooding.

Common stressors degrading riverine wetlands:

• Channelizationofstreams(disconnectingwetlandsfromstreams)

• Invasiveplantspecies• Fillingofwetlands

mammals,andimportantcommercialfisheries.

Common stressors degrading tidal wetlands:

• Wetlanddiking• Ditchingthatalterstidalflow• Invasiveplants• Hardsurfacesthatlimit

marshmigration• Developmentadjacentto

marshes

areas.ManyarenotprotectedbyFederalorStatewetlandregulations.

Common stressors degrading flat wetlands:

• Ditchingtoremovewater• Forestharvesting• Fillingofwetlands• Roads

Tidalwetlandsareregularlyfloodedbythetideandsurroundtheedgeofthebays.Theyarehighlyfertileandaresomeofthemostproductiveecosystemsonearth.Theyprovidecoastalpopulationswithcriticalservicesbyreducingfloodingfromstorms,controllingerosion,improvingwaterqualityandprovidinghabitatforbirds,

Flatwetlandsaretypicallylocatedattheheadwatersofthewatershedandonverylowslopedlands.Thesewetlandscanabsorbheavyprecipitationandfilterwaterslowlytosurfaceandgroundwaters,preventfloodingdownstream,improvewaterquality,andprovidewildlifehabitatinlargeforested

health of riverine wetlands

How are our remaining wetlands faring? health of tidal wetlands

health of flat wetlands

Recommendations: Restore channelized streams to more natural streams, control invasive plants. Recommendations: Minimize development adjacent to wetlands,

restore natural distribution of water, control invasive plants.

Recommendations: Protect large forest blocks, restore natural distribution of water, implement sustainable forest management.

D D+

B-

why monitor wetlands? Understandingtheconditionofwetlandsandhowhumanandnaturallycausedstressorsareimpactingwetlandhealthwillaidresourceagenciesandconservationpartnerstobetterguidewetlandprotectionandrestorationeffortsandinformlandusedecisions.

how are wetlands monitored? DNRECandtheCenterfortheInlandBaysresearched149wetlandsitesinthewatershedwiththeDelawareWetlandAssessmentProtocolsfrom2005-2008.Measurementsofbiologicalandphysicalindicatorsofwetlandconditionaretakenincludingvegetation,soils,hydrology,surroundinglanduse,andstressorsimpactingthewetlands(e.g.,invasiveplants,ditching,fill,developmentandagriculture).

how are wetlands scored?ThemeasurementsofwetlandhealthindicatorsareusedtoproduceconditionandfunctionscoresillustratingthehealthoftheInlandBays’wetlands.Scoresarereflectiveofhowsimilarassessedwetlandsaretoleastdisturbedwetlandsofsimilartype.Thedataarecollectedusingscientificallyrobustfieldprotocolsateachsite.Theoverallcondition(grade)foreachwetlandtypeisanaveragebasedonastatisticallyrepresentativesampleinthewatershed(approximately50sitesforeachwetlandtype).Thepiechartsrepresentthepercentageofsitesrangingfromminimallystressedtoseverelystressedforeachwetlandhabitattype.

Formoreinformationaboutthemethodsusedtocollectthedataandcopiesofthefullreports,seecontactinformationonthelastpage.

what wetlands are at risk for loss?ThisreportcardhighlightsthefactthattheInlandBayswatershedhaslostmuchofitsoriginalwetlands.Manyoftheremainingwetlandsareinpoorhealthandarealsoatrisktobelostundercertaincircumstances.Manynontidalwetlandsarethreatenedbecauseofgapsinexistingregulationsorpossiblyduetolimitationsofenforcementtoreduceillegalimpacts.RecentSupremeCourtdecisionshavecreateddilemmasindeterminingwhichwetlandsandwaterwaysareregulatedundertheCleanWaterAct.Thishasresultedinaperiodofvulnerabilityforsomewetlands.

InDelaware,asmuchas20%ofnontidal/freshwaterwetlandsmaybeconsideredisolated(pendingArmyCorpsdetermination)andconsequentlymaybeunregulated.

Therearewaysthatresearchersandthepubliccanworktogethertobetterprotectthehealthandexistenceofourremainingwetlandsandrestorelostsites.Pleasereadon.

SeverelyStressed36%

MinimallyStressed32%

ModeratelyStressed32%

SeverelyStressed18% Minimally

Stressed42%Moderately

Stressed40%

SeverelyStressed28%

MinimallyStressed16%

ModeratelyStressed56%

C E N T E R F O R T H E I N L A N D B AYS S TAT E O F T H E B AYS R E P O R T S E R I E S 2 0 0 9 -2 0 1 0

Inland Bays Watershed—Thisarearepresentstheentireareathatdrainsintothebays.

Determinedtobethegreateststressorinthewatershed.Presently,87%ofwaterwaysarechannelizedorditched.Aboveisageneralizeddepictionoftheeffectsofchannelization.

sea level rise

Saltmarshes need wide buffers because they move landward as sea level rises.

Rising sea level can reduce salt marsh area, which reduces capacity to filter nutrients and protect adjacent upland areas from storms. Sea levels are expected to rise faster in coming years.

CURRENT SEA LEVEL FUTURE SEA LEVEL

Previous sea level

what is being doneResearchontheimpactofsealevelriseanddeterminingwetlandsthataremostatrisk.

goalAllowmarshestheabilitytomigratelandwardandadapttosealevelrisebyprovidingbuffersbetweenwetlandsanddevelopmentorconstruction.

what you can doRequestthatresourceandlanduseplanningagenciesrequirebuffersthatbetterpreservewetlandsandreducehardenedsurfacesnearwetlands.

what is being doneUsingourwetlandconditiondatatodeveloprestorationandprotectionplanstotargetareasmostinneed.

goalWherefeasible,reconnectstreamswiththeiradjacentriverinewetlands.

what you can doConsidervoluntaryrestorationprogramsifyou’realandowner,supportthefundingofrestorationthroughconservationpartnerssuchastheNaturalResourcesConservationService(NRCS),theU.S.FishandWildlifeService,andDucksUnlimited.

NATURAL RIVERINE WETLAND

working together for wetlands!

You can make a difference by living a more watershed friendly lifestyle:

• Utilizelivingshorelinesratherthanrip-raporbulkheads.

• Reduceimpervioushardsurfacesonyourproperty.

• Landscapewithnativelocalplants.

• Supportbetterwetlandprotectionbycontactingyourlocaldecisionmakers.

• LooktotheWetlandPublicParticipationGuidebookfoundatwww.dnrec.delaware.gov/admin/delawarewetlands

• GetinvolvedinyourwatershedbyvolunteeringwiththeCenterfortheInlandBays!

Supportingtechnicalreportscanbefoundonthelistedwebsites.

Center for the Inland Bays:SallyBoswell302-226-8105outreach@inlandbays.orgwww.inlandbays.org/cib_pm/pub_reports.php

DNREC Water Resources: RebeccaRothweiler302-739-9939rebecca.rothweiler@state.de.uswww.dnrec.delaware.gov/admin/delawarewetlandsLead Author: Rebecca Rothweiler DNREC This document was reviewed by experts from the Center for the Inland Bays, DNREC, and the University of Delaware.

Diverse plants provide good wildlife habitat.

Wetland soils store carbon and excess nutrients. Groundwater carrying pollutants

is filtered through wetlands before going downstream.

Floodwaters are stored and filtered by wetland soils before returning to stream.

Beneficial insects and fish thrive among natural debris that filter water.

Plants less diverse, provide lower quality wildlife habitat.

Wetland soils dry releasing carbon and excess nutrients.

Groundwater carrying pollutants mostly bypasses wetland solids and goes downstream unfiltered.

Stream channels are dug out. Floodwaters cannot be stored and filtered by wetlands and are forced downsteam.

Habitat for beneficial insects and fish is less.

stream channelization & ditching

www.dnrec.delaware.gov/admin/delawarewetlands

NATURAL RIVERINE WETLAND CHANNELIZED RIVERINE WETLAND