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7/28/2019 Erosion Control Field Guide
1/10
1. Protectandexpandmoisturestoringareasofthe
landscape.
2. Stabilizeac;veerosionandpreventfurtherdegrada;on.
3. Restoredispersedflowandincreaseinfiltra;onatevery
opportunity.
4. Cul;vaterestora;veplantcommuni;estobuildsoil.
5. Createsite-specificsolu;onsusingnaturalformsand
processes.
Formoreinforma;onvisit
www.DrylandSolu;ons.com
andwww.QuiviraCoali;on.org
GUIDING PRINCIPLES
By Craig Sponholtz & Avery C. Anderson
2010CSAA
7/28/2019 Erosion Control Field Guide
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Alowgradecontrolstructurebuiltwithasinglelayerofrockonthebedofthe
channel.ORDsstabilizethebedofthechannelbyslowingtheflowofwater,increasingroughness,recrui=ngvegeta=on,capturingsediment,andgraduallyraisingthebedlevel
over=me.ORDsarealsopassivewaterharves=ngstructures.Thesinglelayerofrockis
aneffec=verockmulchthatincreasessoilmoisture,infiltra=on,andplantgrowth.Original
conceptdevelopedbyBillZeedyk.
Design&Construc;on
1. SelectareatobuildtheORD;digashallowfootertrenchandfillwithoneortworowsofrock,sothatnorockprotrudesmorethan2in/5cmabovethebedofthechannel.ThiswillserveasthesplashapronfortheORD.
2. ScaHernaIvegrassandwildflowerseedsintheareawheretheORDistobebuilt.3. StartbuildingatthefooterandconInueupstream,layingdownonelayerofrockhorizontally,asifyouwerebuildinga
rockwall.
4. OncetheORDiscompletelyfilledwithsediment,anotherlayercanbeaddedtofurtherraisethebedofthechannelandcapturemoresediment.TheoriginalORDbecomesthesplashapronforthenewlayer.
Orienta;onofRocks:PlacingrocksverIcallyiscalledbook-stacking,thismakesavery
strongstructure,especiallywhenusingsmallrocks.
tisalsoagoodwaytomakeaslightlyhigher
structure.
DirecIonofflow
2010CSAA
ONE ROCK DAM ORD
STEP1:Digtrench
andbuildfooter
STEP3:Startatfooterand
buildupstream
STEP2:SeedareaSTEP4:WhenORDfillsin,
addanewlayer
Book-stackedrocksareverIcallyplacedRocksplacedflat
7/28/2019 Erosion Control Field Guide
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ONE ROCK DAM
PLANVIEW
Pool=Erosion
Crossover=DeposiIon
Pool=ErosionPROFILECrossover=DeposiIon
1.AlwaysposiIongradecontrolstructuresatmeandercrossovers.
3.AlwaysmaintainchannelcrosssecIontoprotectbanks.
2.PlacementatcrossoversmaintainsnaturalerosionanddeposiIonpaHerns.
Correct ncorrect
CROSSSECTION2010CSAA
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Aheadcutcontrolstructurewherethefaceoftheheadcuthasbeenlaidbacktoa
stableangleofrepose(minimumofa3:1slope),andthencoveredwithasinglelayerofrockmulch.Themulchservestoslowrunoff,increasesoilmoisture,recruitvegeta=on,and
ul=matelypreventtheheadcutfrommigra=ngfurtherupslope.RockMulchRundownsare
ONLYtobeusedonlowenergyheadcuts,likethosefoundinuplandrillsandgullieswithsmall
catchmentareas,andwheresheelowcollectsandentersachannel.Originalconceptby
CraigSponholtz.
Design&Construc;on1. Selectalowenergyheadcutfortreatment.2. Determinetheextentofthe3:1slope.TakecaretobalancethecuXngrequiredtoachievea3:1slopevs.thepotenIaldisturbance
toexisIngvegetaIon.
3. LaybacktheheadcutbycuXngawaysoilfromthetopoftheface,andthenusethecutmaterialtofillthebaseoftheheadcut.Wherepossible,theRundownshouldbetheenIrewidthofthechannelbelowtheheadcut,orwhennochannelexists,thewidthof
theheadcutitself.Narrowheadcutsmayneedtobewidenedtoaccommodatetherockwork.Adjacentheadcuts,separatedby
unerodedfingersofearth,butleadingtothesamechannel,canbecombinedintoasingleRundownstructure.Knockdownthe
unerodedearthbetweentheheadcuts,anduseitasfill.
4.
Compactthefill.5. ScaHernaIvegrassandwildflowerseedandrakethesurfaceoftheRundown.6. DigashallowtrenchonthedownslopesideoftheRundownandfillwithonetotworowsofrock,sothatnorockprotrudesmore
than2in/5cmabovethebedofthechannel.ThiswillserveasthesplashapronfortheRundown.
7. CovertheenIresurfaceoftheRundownwithasinglelayerofrockmulch.ThecenteroftheRundownshouldbethelowestpointinthestructuresothatwaterwillnotrunaroundtheedges.
8. ConInuetolayrockonthesurfaceoftheRundownunIlyoureachtheheightoftheheadcutpour-over.Norocksshouldprotrudeabovethisleveltoallowwatertoflowfreelyoverthestructure.tisveryimportanttoavoidgapsintherockworkbecausegaps
causeweakpointsinthestructure.Fillgapswithsmallgravelifneeded.Toimprovedurability,youcanuseabiodegradablegeotexIle
meshtolinethesurfaceoftheRundownpriortolayingrocks.2010CSAA
ROCK MULCH RUNDOWN
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ROCK MULCHRUNDOWN*
1.Layout3:1slopeoveruplandheadcut.
2.Laybackslope,compactsoil,scaerseed.
3.Covernewslopewithcobblemulch.
4.Timeandprecipita;onwillproduceplantcover.
*Useonlyinlow
energyheadcuts(NOT
in-channelheadcuts!)
2010CSAA
splash
apron
headcutpour-over
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Design&Construc;on1. Selectaheadcutfortreatment;shapeandlaybackthefaceoftheheadcuttocreateauniformsurfaceonwhichtobuild.2. Determinetheheightoftheheadcut.NextmeasureandmarkthelocaIondownstreamfromthefaceoftheheadcutthatistwoto
threeImes(2-3x)theheightoftheheadcut.AtthislocaIondigashallowtrenchandfillwithonetotworowsofrock,sothatno
rockprotrudesmorethan2in/5cmabovethebedofthechannel.ThiswillserveasthesplashapronfortheZuniBowl.
3. ScaHernaIvegrassandwildflowerseedsintheareawheretheZuniBowlistobebuilt.4. Gatherthelargestrocksavailable,andplacetheminarowjustupstreamfrom,andincontactwiththesplashapron.Theserocks
shouldsitatanelevaIonapproximatelythetotalheightoftheheadcut.Thiswillserveasthelowerpour-overoftheZuniBowl.
5. ArmortheboHomoftheplungepoolwithasinglelayerofrocks.PlacetheserocksatauniformheighttocreateastablefoundaIonfortherestoftheZuniBowl.
6. StarIngjustupstreamfromthelowerpour-over,laycoursesofrockaroundthefaceoftheheadcut.Thiswillformthewallsofthebowl.Maintaincontactwiththeshapedsurface.Thestructurewillhavemoreintegrityifbuiltwithlayersofoff-setrocksthatforma
slopingwallaroundtheheadcut,asopposedtomerelyliningthefacewithrocks.mprovethedurabilityofthestructurebyavoiding
gapsintherockwork.AsanextraprecauIon,youcanusebiodegradablegeotexIlefabrictolinethefaceoftheheadcutpriorto
layingrocks.
7. ConInuetolaycoursesofrockaroundthefaceoftheheadcutunIlyoureachtheheightoftheheadcutpour-over.Norocksshouldprotrudeabovethisleveltoallowwatertoflowfreelyoverthestructure.
8. ConstructaORDdownstreamfromtheZuniBowl.PlacetheupstreamedgeoftheORDapproximatelyfourtosixImes(4-6x)theheightoftheheadcutawayfromtheheadcutpour-over.
ZUNI BOWLAheadcutcontrolstructurecomposedofrocklinedstepfallsandplungepoolsthat
preventsheadcutsfromcon=nuingtomigrateupstream.ZuniBowlsstabilizeac=vely
erodingheadcutsbydissipa=ngtheenergyoffallingwaterattheheadcutpour-over
andthebedofthechannel.Thestructureconvertsthesinglecascadeofaneroding
headcutintoaseriesofsmallerstepfalls.ZuniBowlsalsoservetomaintainsoil
moistureonthefaceoftheheadcut,encouragingtheestablishmentofprotec=ve
vegeta=on.OriginalconceptdevelopedbyBillZeedykandthepeopleofZuniPueblo.
2010CSAA
7/28/2019 Erosion Control Field Guide
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ZUNI BOWL
lowerpour-over
[heightofheadcutpour-over]
splashapron
headcutpour-over
2-3xheightofheadcut2010CSAA
onerock
dam
4-6xheightofheadcut
plungepool
plungepool
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MEDIA LUNATherearetwotypesofMediaLunastructuresbothusedtomanagesheetflow
andpreventerosion.Sheetflowcollectors(=psDOWN)preventerosion(i.e.
headcuts)attheheadofrillsandgulliesbycrea=ngastabletransi=onfromsheet
flowtochannelflowatthecollec=onpoint.Sheetflowspreaders(=psUP)areused
onrela=velyflatgroundtodisperseerosivechannelizedflowandreestablishsheet
flowwhereitonceoccurred.OriginalconceptdevelopedbyVanClothier,and
expandeduponbyCraigSponholtz.
Design&Construc;on1. denIfywhichtypeofMediaLuna(i.e.IpsUPorIpsDOWN)isappropriateforthetreatmentsite.2. fthetreatmentsiteisatthecollecIonpointofanetworkofrills(
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MEDIA LUNASheetFlowSpreader(=psUP)
Spreadsrunofffromchannelsand
iniIatessheetflow.
SheetFlowCollector(=psDOWN)
Preventsdevelopingrillsandgullies
fromerodingupslope.
2010CSAA
collection
point
sheet flow
splash
apron
7/28/2019 Erosion Control Field Guide
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OneRockDam RockMulch
Rundown
MediaLuna(;ps
UP)
ZuniBowl
2
010CSAA
W
henpossible
usematerialsavailableon-site.
N
OTE:manytypeso
frockcanbeused
tobuildthesestructures.
Formoreinform
a>onvisitwww
.DrylandSolu>o
ns.com
andwww.QuiviraCoali>on.org