Strom: Storm Water Management Exam
Questions and Answers
What iiis iithe iiprimary iiconsequence iiof iisurface iichanges? ii- iiAnswers ii-developed iisites
iilose iimuch iiof iitheir iinatural iistorm iiwater iistorage iicapacity. iiThe iiloss iiof iivegetation,
iiorganic iilitter, iiand iichanges iiin iisurface iicharacteristics, iisuch iias iiroughness iiand
iiperviousness, iiresult iiin iithe iirapid iiconversion iiof iirainfall iito iistorm iiwater iirunoff.
All iistorm iiwater iimanagement iipractices iimust iibe iiwhat ii(3) iithings? ii- iiAnswers ii-- iisite
iispecific
- iiregion iispecific
- iiclimate iispecific
Define iisubsurface iirunoff ii- iiAnswers ii-is iistorm iiwater iithat iiinfiltrates iiand iimoves
iithrough iithe iisoil iiboth iihorizontally iiand iivertically. iiThe iirate iiof iimovement iiis
iiinfluenced iiby iisoil iipermeability iiand iiusually iioccurs iiat iia iimuch iislower iirate iithan
iisurface iirunoff.
When iidoes iisurface iirunoff iioccur? ii- iiAnswers ii-For iiimpervious iisurfaces, iirunoff
iioccurs iiimmediately. iiFor iipervious iisurfaces, iithe iiintensity iiof iiprecipitation iimust
iiexceed iithe iiinfiltration iirate, iithat iiis, iithe iisurface iimust iibe iisaturated iibefore iirunoff
iican iioccur.
What iiare iithe iienvironmental iiimpacts iifrom iichanges iiin iistorm iiwater iidrainage
iipatterns? ii- iiAnswers ii-- iiincreased iiflood iipotential iidue iito iiincreases iiin iipeak iiflow
iirates
- iidecreased iigroundwater iisupply iicaused iiby iireduced iiinfiltration
- iiincreased iisoil iierosion iiand iisedimentation iibrought iiabout iiby iigreater iirunoff
iivolumes iiand iivelocities
- iiincreased iipetrochemical iipollution iifrom iistreet iiand iihighway iirunoff
- iicontamination iiof iiwinter iirunoff iiby iisalt iiand iisand iiin iicolder iiregions
What iichanges iiin iistream iihydrology iican iiresult iifrom iidevelopment? ii- iiAnswers ii--
iipeak iidischarges, iiwhich iican iibe iias iimuch iias iitwo iito iifive iitimes iithe iipredevelopment
iirate, iigenerally iiincrease iithe iifrequency iiand iiseverity iiof iiflooding
- iihigher iivelocities iicoupled iiwith iiincreased iiimperviousness iimay iialso iiresult iiin
iireduced iistream iiflow iiduring iiextended iidry iiperiods iicaused iiby iireduced iiinfiltration.
iiGroundwater iithat iiwould iinormally iibe iirecharged iiduring iiwet iiperiods iiand iireleased
iislowly iifrom iisoil iiduring iidry iiperiods iiis iilost iias iisurface iirunoff
- iistream iigeometry iialso iichanges. iiStreams iiare iiwidened iidue iito iiincreased iivolume
iiand iivelocity, iiwhich iiresults iiin iiincreased iistream iibank iierosion.
, - iiUsually iithe iistream iibank iiis iiundercut, iidestabilizing iivegetation iiand, iiin iiturn,
iiexacerbating iithe iierosion iiproblem. iiEroded iimaterial iiis iideposited iiin iistream
iichannels iias iisediment, iiwhich iireduces iistream iiflow iicapacity. ii
- iiFlood iielevations iiare iiraised; iias iinoted, iithis iiphenomenon iiincreases iithe iiextent iiof
iithe iiarea iiat iirisk iiof iiflood iidamage
Where iido iicontaminants iicome iifrom? ii- iiAnswers ii-- iipollutants iiare iiaccumulated iion
iipaved iisurfaces iiand iiare iiflushed iifrom iithese iisurfaces iiduring iia iirainstorm
- iicontaminants iimay iibe iireleased iithrough iicorrosion, iidecay, iioil iiand iifuel iileaks,
iileaching iior iiwearing iiaway iiof iiconstruction iimaterials iiand iicoatings, iibrake iilinings,
iitires, iiand iicatalytic iiconverters.
- iideveloped iiareas, iias iiwell iias iiagricultural iiareas, iicontribute iiherbicides, iipesticides,
iifertilizers, iiwhich iistimulate iialgal iigrowth iiand iireduce iithe iiavailability iiof iioxygen iiin
iiwater
- iifallen iileaves iiand iianimal iipoops iithat iiwould iinormally iidecompose iiin
iiunderdeveloped iior iilow-density iisettings iiare iimore iieasily iiwashed iifrom iipaved
iisurfaces, iifurther iiincreasing iinutrient iiand iibacteria iilevels iiin iistreams, iiponds, iiand
iilakes
Changes iiin iistream iihydrology iiand iigeometry, iicombined iiwith iireduced iiwater iiquality,
iidecrease iithe iivalue iiof iiwhat? ii- iiAnswers ii-aquatic, iistream iibank, iiand iifloodplain
iihabitats. iiNot iionly iiare iistream iichannels iiand iiflows iialtered iiand iipollution iilevels
iiraised, iibut iithese iiconditions iiare iifurther iiexacerbated iiby iilow iisummer iiflows iiand
iihigher iiwater iitemperatures.
How iiwas iistorm iiwater iimanaged iiin iithe iipast iiand iihow iiis iiit iidifferent iinow? ii-
iiAnswers ii-- iiHistorically, iithe iiprimary iiconcern iiin iidealing iiwith iistorm iiwater iirunoff
iiwas iito iiremove iiit iias iiquickly iias iipossible. iiTraditionally, iithis iiwas iiaccomplished iiby
iiconveying iirunoff iiby iistorm iisewers, iiswales, iigutters, iiand iichannels iito iithe iinearest
iiwater iibody, iiusually iia iistream iior iiriver.
- iimore iirecently iistorm iiwater iimanagement iipractices iihave iirecognized iithe iineed iifor
iicontrolling iioff-site iiimpacts iicaused iiby iiincreased iirunoff. iiThe iiobjectives iiof iithese
iirevised iipractices iiare iitwofold:
ii1. iito iireduce iidownstream iiflooding iithrough iithe iiuse iiof iidetention iifacilities iithat iistore
iiand iirelease iirunoff iiat iia iicontrolled iirate.
ii2. iito iireduce iiflooding iidamage iiby iirestricting iifloodplain iidevelopment. iiMost
iilegislation iiat iieither iithe iistate iior iilocal iilevel iistates iithat iithe iipeak iirate iiof iirunoff iiafter
iidevelopment iicannot iiexceed iithe iirate iiprior iito iidevelopment.
In iithe iimost iirecent iiphilosophy, iiin iiaddition iito iithe iivolume iiand iirate iiof iirunoff. iiOne
iiprimary iimanagement iiobjective iiis iiwhat? ii- iiAnswers ii-deal iiwith iirunoff iion-site iirather
iithan iitransporting iithe iiproblem iioff-site!
a iibasic iiobjective iiof iiany iisite iidesign iishould iibe iito iiminimize iihydrologic iiproblems iiby
iipreserving iiand iimaintaining iithe iipredevelopment iidrainage iipatterns iito iithe iigreatest
Questions and Answers
What iiis iithe iiprimary iiconsequence iiof iisurface iichanges? ii- iiAnswers ii-developed iisites
iilose iimuch iiof iitheir iinatural iistorm iiwater iistorage iicapacity. iiThe iiloss iiof iivegetation,
iiorganic iilitter, iiand iichanges iiin iisurface iicharacteristics, iisuch iias iiroughness iiand
iiperviousness, iiresult iiin iithe iirapid iiconversion iiof iirainfall iito iistorm iiwater iirunoff.
All iistorm iiwater iimanagement iipractices iimust iibe iiwhat ii(3) iithings? ii- iiAnswers ii-- iisite
iispecific
- iiregion iispecific
- iiclimate iispecific
Define iisubsurface iirunoff ii- iiAnswers ii-is iistorm iiwater iithat iiinfiltrates iiand iimoves
iithrough iithe iisoil iiboth iihorizontally iiand iivertically. iiThe iirate iiof iimovement iiis
iiinfluenced iiby iisoil iipermeability iiand iiusually iioccurs iiat iia iimuch iislower iirate iithan
iisurface iirunoff.
When iidoes iisurface iirunoff iioccur? ii- iiAnswers ii-For iiimpervious iisurfaces, iirunoff
iioccurs iiimmediately. iiFor iipervious iisurfaces, iithe iiintensity iiof iiprecipitation iimust
iiexceed iithe iiinfiltration iirate, iithat iiis, iithe iisurface iimust iibe iisaturated iibefore iirunoff
iican iioccur.
What iiare iithe iienvironmental iiimpacts iifrom iichanges iiin iistorm iiwater iidrainage
iipatterns? ii- iiAnswers ii-- iiincreased iiflood iipotential iidue iito iiincreases iiin iipeak iiflow
iirates
- iidecreased iigroundwater iisupply iicaused iiby iireduced iiinfiltration
- iiincreased iisoil iierosion iiand iisedimentation iibrought iiabout iiby iigreater iirunoff
iivolumes iiand iivelocities
- iiincreased iipetrochemical iipollution iifrom iistreet iiand iihighway iirunoff
- iicontamination iiof iiwinter iirunoff iiby iisalt iiand iisand iiin iicolder iiregions
What iichanges iiin iistream iihydrology iican iiresult iifrom iidevelopment? ii- iiAnswers ii--
iipeak iidischarges, iiwhich iican iibe iias iimuch iias iitwo iito iifive iitimes iithe iipredevelopment
iirate, iigenerally iiincrease iithe iifrequency iiand iiseverity iiof iiflooding
- iihigher iivelocities iicoupled iiwith iiincreased iiimperviousness iimay iialso iiresult iiin
iireduced iistream iiflow iiduring iiextended iidry iiperiods iicaused iiby iireduced iiinfiltration.
iiGroundwater iithat iiwould iinormally iibe iirecharged iiduring iiwet iiperiods iiand iireleased
iislowly iifrom iisoil iiduring iidry iiperiods iiis iilost iias iisurface iirunoff
- iistream iigeometry iialso iichanges. iiStreams iiare iiwidened iidue iito iiincreased iivolume
iiand iivelocity, iiwhich iiresults iiin iiincreased iistream iibank iierosion.
, - iiUsually iithe iistream iibank iiis iiundercut, iidestabilizing iivegetation iiand, iiin iiturn,
iiexacerbating iithe iierosion iiproblem. iiEroded iimaterial iiis iideposited iiin iistream
iichannels iias iisediment, iiwhich iireduces iistream iiflow iicapacity. ii
- iiFlood iielevations iiare iiraised; iias iinoted, iithis iiphenomenon iiincreases iithe iiextent iiof
iithe iiarea iiat iirisk iiof iiflood iidamage
Where iido iicontaminants iicome iifrom? ii- iiAnswers ii-- iipollutants iiare iiaccumulated iion
iipaved iisurfaces iiand iiare iiflushed iifrom iithese iisurfaces iiduring iia iirainstorm
- iicontaminants iimay iibe iireleased iithrough iicorrosion, iidecay, iioil iiand iifuel iileaks,
iileaching iior iiwearing iiaway iiof iiconstruction iimaterials iiand iicoatings, iibrake iilinings,
iitires, iiand iicatalytic iiconverters.
- iideveloped iiareas, iias iiwell iias iiagricultural iiareas, iicontribute iiherbicides, iipesticides,
iifertilizers, iiwhich iistimulate iialgal iigrowth iiand iireduce iithe iiavailability iiof iioxygen iiin
iiwater
- iifallen iileaves iiand iianimal iipoops iithat iiwould iinormally iidecompose iiin
iiunderdeveloped iior iilow-density iisettings iiare iimore iieasily iiwashed iifrom iipaved
iisurfaces, iifurther iiincreasing iinutrient iiand iibacteria iilevels iiin iistreams, iiponds, iiand
iilakes
Changes iiin iistream iihydrology iiand iigeometry, iicombined iiwith iireduced iiwater iiquality,
iidecrease iithe iivalue iiof iiwhat? ii- iiAnswers ii-aquatic, iistream iibank, iiand iifloodplain
iihabitats. iiNot iionly iiare iistream iichannels iiand iiflows iialtered iiand iipollution iilevels
iiraised, iibut iithese iiconditions iiare iifurther iiexacerbated iiby iilow iisummer iiflows iiand
iihigher iiwater iitemperatures.
How iiwas iistorm iiwater iimanaged iiin iithe iipast iiand iihow iiis iiit iidifferent iinow? ii-
iiAnswers ii-- iiHistorically, iithe iiprimary iiconcern iiin iidealing iiwith iistorm iiwater iirunoff
iiwas iito iiremove iiit iias iiquickly iias iipossible. iiTraditionally, iithis iiwas iiaccomplished iiby
iiconveying iirunoff iiby iistorm iisewers, iiswales, iigutters, iiand iichannels iito iithe iinearest
iiwater iibody, iiusually iia iistream iior iiriver.
- iimore iirecently iistorm iiwater iimanagement iipractices iihave iirecognized iithe iineed iifor
iicontrolling iioff-site iiimpacts iicaused iiby iiincreased iirunoff. iiThe iiobjectives iiof iithese
iirevised iipractices iiare iitwofold:
ii1. iito iireduce iidownstream iiflooding iithrough iithe iiuse iiof iidetention iifacilities iithat iistore
iiand iirelease iirunoff iiat iia iicontrolled iirate.
ii2. iito iireduce iiflooding iidamage iiby iirestricting iifloodplain iidevelopment. iiMost
iilegislation iiat iieither iithe iistate iior iilocal iilevel iistates iithat iithe iipeak iirate iiof iirunoff iiafter
iidevelopment iicannot iiexceed iithe iirate iiprior iito iidevelopment.
In iithe iimost iirecent iiphilosophy, iiin iiaddition iito iithe iivolume iiand iirate iiof iirunoff. iiOne
iiprimary iimanagement iiobjective iiis iiwhat? ii- iiAnswers ii-deal iiwith iirunoff iion-site iirather
iithan iitransporting iithe iiproblem iioff-site!
a iibasic iiobjective iiof iiany iisite iidesign iishould iibe iito iiminimize iihydrologic iiproblems iiby
iipreserving iiand iimaintaining iithe iipredevelopment iidrainage iipatterns iito iithe iigreatest
