给排水科学与工程专业英语版本教材

CONTENTS

PartOneIntroduction1

Unit1HydrologicCycle1

ImportantWordsandExpressions3

Notes4

Exercises4

ReadingMaterialA6

Notes8

ReadingMaterialB9

Notes11

Unit2WaterLegislationandRegulation12

ImportentWordsandExpressions14

Notes15

Exercises15

ReadingMaterialA17

Notes19

ReadingMaterialB20

Notes22

Unit3AnalyticalTechniqueandMethodology24

ImportantWordsandExpressions26

Notes27

Exercises27

ReadingMaterialA29

Notes31

ReadingMaterialB32

Notes34

PartTwoWaterSupplyandSewerageSystem35

Unit4WaterSupplySystem35

ImportantWordsandExpressions37

Notes37

Exercises38

ReadingMaterialA40

Notes42

ReadingMaterialB43

Notes45

Unit5WastewaterCollectionandSewerageSystemDesign46

ImportantWordsandExpressions49

Notes50

Exercises50

ReadingMaterialA52

Notes55

ReadingMaterialB56

Notes58

Unit6StormwaterCollectionandSewerDesign59

ImportantWordsandExpressions62

Notes62

Exercises62

ReadingMaterialA64

Notes67

ReadingMaterialB68

Notes71

Unit7PumpsandPumpingStations72

ImportantWordsandExpressions75

Notes76

Exercises76

ReadingMaterialA78

Notes80

ReadingMaterialB81

Notes84

PartThreePhysical-ChemicalTreatmentProcess85

Unit8CoagulationandFlocculation85

ImportantWordsandExpressions88

Notes89

Exercises89

ReadingMaterialA91

Notes94

ReadingMaterialB95

Notes98

Unit9Sedimentation99

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ReadingMaterialA错误!未定义书签。

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ReadingMaterialB错误!未定义书签。

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Unit10Filtration113

ImportantWordsandExpressions115

Notes:116

Exercises116

ReadingMaterialA118

Notes121

ReadingMaterialB123

Notes126

Unit11ChemicalOxidation127

ImportantWordsandExpressions131

Notes132

Exercises132

ReadingMaterialA134

Notes137

ReadingMaterialB138

Notes141

Unit12Adsorption142

ImportantWordsandExpressions145

Notes146

Exercises147

ReadingMaterialA149

Notes152

ReadingMaterialB153

Notes156

Unit13MembraneFiltrationProcesses157

ImportentWordsandExpressions159

Notes160

Exercises161

ReadingMaterialA163

Notes165

ReadingMaterialB166

Notes168

PartFourBiologicalTreatmentProcess169

Unit14ActivatedSludgeProcess169

ImportantWordsandExpressions171

Notes172

Exercises172

ReadingMaterialA174

Notes176

ReadingMaterialB177

Notes179

Unit15AttachedGrowthBiologicalTreatmentProcess180

ImportantWordsandExpressions182

Notes183

ReadingMaterialA185

Notes187

ReadingMaterialB188

Notes191

Unit16AnaerobicBiologicalTreatment192

ImportantWordsandExpressions195

Notes196

Exercises196

ReadingMaterialA198

Notes200

ReadingMaterialB201

Notes203

PartFiveSludgeTreatment,ReuseandDisposal204

Unit17Thickening204

ImportantWordsandExpressions206

Notes207

Exercises207

ReadingMaterialA209

Notes212

ReadingMaterialB213

Notes215

Unit18AnaerobicDigestion216

ImportantWordsandExpressions219

Notes219

Exercises220

ReadingMaterialA222

Notes225

ReadingMaterialB226

Notes229

Unit19Dewatering230

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Unit20SludgeUtilizationandDisposal244

ImportantWordsandExpressions246

Notes246

Exercises247

ReadingMaterialA249

Notes251

ReadingMaterialB252

Notes254

PartsixBuildingWaterSupplyandDrainage255

Unit21ColdWaterSupply255

ImportantWordsandExpressions257

Notes258

Exercises258

ReadingMaterialA260

Notes262

ReadingMaterialB263

Notes266

Unit22Building-DrainageSystem267

ImportantWordsandExpressions269

Notes269

Exercises269

ReadingMaterialA271

Notes273

ReadingMaterialB274

Notes276

Unit23Fire-FightingSystems278

ImportantWordsandExpressions281

Notes281

Exercises282

ReadingMaterialA283

Notes284

ReadingMaterialB285

Notes286

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PartOneIntroduction

Unit1HydrologicCycle

Thehydrologiccycle,alsoknownasthewatercycleorH2Ocycle,describesthe

continuousmovementofwateron,aboveandbelowthesurfaceoftheearth.Watercan

changestatesamongliquid,vapour,andsolidatvariousplacesinthewatercycle.Although

thebalanceofwateronEarthremainsfairlyconstantovertime,individualwatermolecules

cancomeandgo,inandoutoftheatmosphere.Thewatermovesfromonereservoirto

another,suchasfromrivertoocean,orfromtheoceantotheatmosphere,bythephysical

processesofevaporation,condensation,precipitation,infiltration,runoff,andsubsurfaceflow.

⑴Insodoing,thewatergoesthroughdifferentphases:liquid,solid,andgas.

Thewatercycleinvolvestheexchangeofheatenergy,whichleadstotemperature

changes.Forinstance,intheprocessofevaporation,watertakesupenergyfromthe

surroundingsandcoolstheenvironment.Conversely,intheprocessofcondensation,water

releasesenergytoitssurroundings,warmingtheenvironment.Thewatercyclefigures

significantlyinthemaintenanceoflifeandecosystemsonEarth.Evenaswaterineach

reservoirplaysanimportantrole,thewatercyclebringsaddedsignificancetothepresenceof

wateronourplanet.Bytransferringwaterfromonereservoirtoanother,thewatercycle

purifieswater,replenishesthelandwithfreshwater,andtransportsmineralstodifferentparts

oftheglobe.f2lItisalsoinvolvedinreshapingthegeologicalfeaturesoftheEarth,through

suchprocessesaserosionandsedimentation.Inaddition,asthewatercyclealsoinvolvesheat

exchange,itexertsaninfluenceonclimateaswell.

Thesun,whichdrivesthewatercycle,heatswaterinoceansandseas.Waterevaporates

aswatervaporintotheair.Iceandsnowcansublimatedirectlyintowatervapor.

Evapotranspirationiswatertranspiredfromplantsandevaporatedfromthesoil.Risingair

currentstakethevaporupintotheatmospherewherecoolertemperaturescauseittocondense

intoclouds.Aircurrentsmovewatervaporaroundtheglobe,cloudparticlescollide,grow,

andfalloutoftheskyasprecipitation.Someprecipitationfallsassnoworhail,sleet,andcan

accumulateasicecapsandglaciers,whichcanstorefrozenwaterforthousandsofyears.

Mostwaterfallsbackintotheoceansorontolandasrain,wherethewaterflowsoverthe

groundassurfacerunoff.Aportionofrunoffentersriversinvalleysinthelandscape,with

streamflowmovingwatertowardstheoceans.Runoffandgroundwaterarestoredas

freshwaterinlakes.Notallrunoffflowsintorivers,muchofitsoaksintothegroundas

infiltration.Somewaterinfiltratesdeepintothegroundandreplenishesaquifers,whichstore

freshwaterforlongperiodsoftime.Someinfiltrationstaysclosetothelandsurfaceandcan

seepbackintosurface-waterbodies(andtheocean)asgroundwaterdischarge.Some

groundwaterfindsopeningsinthelandsurfaceandcomesoutasfreshwatersprings.Over

time,thewaterreturnstotheocean,whereourwatercyclestarted.

Theresidencetimeofareservoirwithinthehydrologiccycleistheaveragetimeawater

moleculewillspendinthatreseroir.Itisameasureoftheaverageageofthewaterinthat

reservoir.Groundwatercanspendover10,000yearsbeneathEarth'ssurfacebeforeleaving.

Particularlyoldgroundwateriscalledfossilwater.Waterstoredinthesoilremainstherevery

briefly,becauseitisspreadthinlyacrosstheEarth,andisreadilylostbyevaporation,

transpiration,streamflow,orgroundwaterrecharge.131Afterevaporating,theresidencetime

intheatmosphereisabout9daysbeforecondensingandfallingtotheEarthasprecipitation.

Themajoricesheet-AntarcticaandGreenland-storeiceareforverylongperiods.Icefrom

Antarcticahasbeenreliablydatedto800,000yearsbeforepresent,thoughtheaverage

residencetimeisshorter.

Inhydrology,residencetimescanbeestimatedintwoways.Themorecommonmethod

reliesontheprincipleofconservationofmassandassumestheamountofwaterinagiven

reservoirisroughlyconstant.Withthismethod,residencetimesareestimatedbydividingthe

volumeofthereservoirbytheratebywhichwatereitherentersorexitsthereservoir.

Conceptually,thisisequivalenttotiminghowlongitwouldtakethereservoirtobecome

filledfromemptyifnowaterweretoleave(orhowlongitwouldtakethereservoirtoempty

fromfullifnowaterweretoenter).Analternativemethodtoestimateresidencetimes,which

isgaininginpopularityfordatinggroundwater,istheuseofisotopictechniques.Thisisdone

inthesubfieldofisotopehydrology.

Humanactivitiesthatalterthewatercycleinclude:

•Agriculture

•Industry

•Alterationofthechemicalcompositionoftheatmosphere

•Constructionofdams

•Deforestationandafforestation

•Removalofgroundwaterfromwells

•Waterabstractionfromrivers

•Urbanization

Effectsonclimate:Thewatercycleispoweredfromsolarenergy.86%oftheglobal

evaporationoccursfromtheoceans,reducingtheirtemperaturebyevaporativecooling.

Withoutthecooling,theeffectofevaporationonthegreenhouseeffectwouldleadtoamuch

highersurfacetemperatureof67℃(153°F),andawarmerplanet.

Aquiferdrawdownoroverdraftingandthepumpingoffossilwaterincreasesthetotal

amountofwaterinthehydrospherethatissubjecttotranspirationandevaporationthereby

causingaccretioninwatervapourandcloudcoverwhicharetheprimaryabsorbersofinfrared

radiationintheEarth'satmosphere.141Addingwatertothesystemhasaforcingeffectonthe

wholeearthsystem,anaccurateestimateofwhichhydrogeologicalfactisyettobequantified.

ImportantWordsandExpressions

hydrology口加乂］口口_1人口口口］n.水文学，水文地理学

reservoirn,蓄水池；贮液器；储藏；蓄积

evaporation[AD_•/□□□□□□□□□n.蒸发，发散；消失

condensation[口口1口口11口口工口口卬口口卬口]n.冷凝；冷凝液；凝结的水珠；节略

precipitation[工口口工⑷口_卬口口]n.匆促；沉淀；(雨等)降落；某地区降雨等的量

figure[D^DD]n.数字；算术；图解；轮廓vt.估计；推测；认为

replenish□工DY如口□□口vt.补充；重新装满；把...装满；

sedimentation[□山口口在口口_□□口口口]n.沉淀，沉降

evaportranspirationn.作物腾发量

sublimatePJ]$£]+□_]n.升华物vt.(使某物质)升华；使净化；纯化

infiltration[口口口村内~山口口口口]n.渗透

residencetime停留时间

deforestation[□□□□□＞工工口一□口口口]n,采伐森林，森林开伐

afforestation[口口/•.上□!«□□□□□□n.造林，造林地区

叫uifer[□•.•口工乂1口n.地下蓄水层，砂石含水层

Notes

[1]由于蒸发、凝结、降水、入渗、径流、潜流等物理过程，水从一个蓄水池到另一个,

比如从河流到海洋，从海洋到大气。

[2]通过水从一个蓄水池到另一个，水循环净化了水，为陆地补充了淡水，把矿物质运

送到地球不同的部位。

[3]土壤中储存的水停留很短暂，因为土壤水薄薄的分布在地表，通过蒸发、蒸腾、河

川径流和地下水补给而容易消失。

[4]地下水位降低或者超采以及化石水的抽取增加了水圈中水的总量，水圈中的水易于

蒸腾和蒸发，从而产生水蒸气以及云量的堆积，这些是地球大气中红外辐射最主要的吸

收体。

Exercises

1.AnsweringthefollowingquestionsinEnglishaccordingtothetext:

(1)Howmanyphysicalprocesseshappenedinhydrologiccycleaccordingtothetext?

(2)Trytoexplainthemethodofestimatingtheresidencetimeofthewater.

2.Usingthefollowingeachwordtomakeupthesentences,respectively:

(1)Hydrologiccycle

(2)subsurfaceflow

(3)runoff

(4)residencetime

(5)conservationofmass

3.PutthefollowingEnglishintoChinese:

(1)Groundwaterisanimportantdirectsourceofsupplythatistappedbywells,aswell

asasignificantindirectsourcesincesurfacestreamsareoftensuppliedbysubterraneanwater.

Nearthesurfaceoftheearth,inthezoneofaeration,soilporespacescontainbothairand

water.Thiszone,whichmayhavezerothicknessinswamplandsandbeseveralhundredfeet

thickinmountainousregions,containsthreetypesofmoisture.Afterastorm,gravitywateris

intransitthroughthelargersoilporespaces.Capillarywaterisdrawnsmallporespacesby

capillaryactionandisavailableforplantuptake.Hygroscopicmoistureisheldinplaceby

molecularforcesduringallexceptthedriestclimaticconditions.Moisturefromthezoneof

aerationcannotbetappedasawatersupplysource.

(2)Inthezoneofsaturation,locatedbelowthezoneofaeration,thesoilporesarefilled

withwater,andthisiswhatwecallgroundwater.Astratumthatcontainsasubstantialamount

ofgroundwateriscalledanaquifer.Atthesurfacebetweenthetwozones,calledthewater

tableorphreaticsurface,thehydrostaticpressureinthegroundwaterisequaltothe

atmospherepressure.Anaquifermayextendtogreatdepths,butbecausetheweightof

overburdenmaterialgenerallyclosesporespaces,littlewaterisfoundatdepthsgreaterthan

600m(1200ft).Theamountofwaterthatwilldrainfreelyfromanaquiferisknownas

specificyield.

4.PutthefollowingChineseintoEnglish:

(1)水循环

(2)蒸发

(3)停留时间

(4)地球上的水不是静止的，而是不断运动变化和相互交换的。

(5)在太阳辐射和地心吸引力的作用下，地球上各种状态的水从海洋面、江河面.、

湖沼面、陆地面和动植物表面蒸发、蒸腾变成水汽，上升于空中，或停留在空中，或

被气流带到其他地区，在适当条件下凝结，然后以降水形式落到海洋面或陆地表面。

ReadingMaterialA

TheWaterBalance

Inhydrology,awaterbalanceequationcanbeusedtodescribetheflowofwaterinand

outofasystem.Asystemcanbeoneofseveralhydrologicaldomains,suchasacolumnof

soiloradrainagebasin.Waterbalancecanalsorefertothewaysinwhichanorganism

maintainswaterindryorhotconditions.Itisoftendiscussedinreferencetoplantsor

arthropods,whichhaveavarietyofwaterretentionmechanisms,includingalipidwaxy

coatingthathaslimitedpermeability.1,1

Waterbalancecalculations

Waterbalancecalculationscanhelptodetermineifadrainageareaislargeenoughorhas

therightcharacteristicstosupportapermanentpoolofwaterduringaverageorextreme

.[21

conditions.1J

Whenindoubt,awaterbalancecalculationmaybeadvisablefbrretentionpondand

wetlanddesign.Thedetailsofarigorouswaterbalancearebeyondthescopeofthismanual.

However,asimplifiedprocedureisdescribedhereinthatwillprovideanestimateofpool

viabilityandpointtotheneedfbrmorerigorousanalysis.Waterbalancecanalsobeusedto

helpestablishplantingzonesinawetlanddesign.

Basicequations

Waterbalanceisdefinedasthechangeinvolumeofthepermanentpoolresultingfrom

thetotalinflowminusthetotaloutflow(actualorpotential).Equation1-1presentsthis

calculation.

△(1-1)

where

△=deltaorchangein

V=pondvolume(ac-ft)

X=thesumof

I=Inflows(ac-ft)

O=Outflows(ac-ft)

Theinflowsconsistofrainfall,runoffandbaseflowintothepond.Theoutflowsconsist

ofinfiltration,evaporation,evapotranspiration,andsurfaceoverflowoutofthepondor

wetland.Equation1-1canbeexpandedtoreflectthesefactors,asshowninEquation1-2.

KeyvariablesinEquation1-2arediscussedindetailbelowtheequation.

AV=PA+R0+BrlA-EA-EtA-Of(1-2)

where

P=precipitation(ft)

A=areaofpond(ac)

Ro=runoff(ac-ft)

Bf=baseflow(ac-ft)

I=infiltration(ft)

E=evaporation(ft)

Et=evapotranspiration(ft)

Of=overflow(ac-ft)

Rainfall(P)MonthlyrainfallvaluescanbeobtainedfromtheNationalWeatherService

climatologyat/mrx/climat.htm.Monthlyvaluesarecommonly

usedforcalculationsofvaluesoveraseason.Rainfallisthenthedirectamountthatfallson

thepondsurfacefortheperiodinquestion.Whenmultipliedbythepondsurfacearea(in

acres)itbecomesacre-feetofvolume.

Runoff(Ro)Runoffisequivalenttotherainfallfortheperiodtimestheefficiencyof

thewatershed,whichisequaltotheratioofrunofftorainfall(Q/P).Inlieuofgage

information,Q/Pcanbeestimatedoneofseveralways.Thebestmethodwouldbetoperform

long-termsimulationmodelingusingrainfallrecordsandawatershedmodel.

Baseflow(B)Moststormwaterpondsandwetlandshavelittle,ifany,baseflow,as

theyarerarelyplacedacrossperennialstreams.Ifsoplaced,baseflowmustbeestimatedfrom

observationorthroughtheoreticalestimates.Methodsofestimationandbaseflowseparation

canbefoundinmosthydrologytextbooks.

Infiltration(I)Infiltrationisaverycomplexsubjectandcannotbecoveredindetailhere.

Theamountofinfiltrationdependsonsoils,watertabledepth,rocklayers,surface

disturbance,thepresenceorabsenceofalinerinthepond,andotherfactors.

Evaporation(E)Evaporationisfromanopenlakewatersurface.Evaporationrates

aredependentondifferencesinvaporpressure,which,inturn,dependontemperature,wind,

atmosphericpressure,waterpurity,andshapeanddepthofthepond.⑶Itisestimatedor

measuredinanumberofways,whichcanbefoundinmosthydrologytextbooks.Pan

evaporationmethodsarealsoused,thoughtherearenolongerpanevaporationsitesactivein

KnoxCounty.FormerlypanevaporationmethodswereutilizedattheKnoxvilleExperiment

Station.

Evapotranspiration(Et)Evapotranspirationconsistsofthecombinationofevaporation

andtranspirationbyplants.TheestimationofEtforcropsiswelldocumentedandhasbecome

standardpractice.However,theestimatingmethodsforwetlandsarenotdocumented,norare

thereconsistentstudiestoassistthedesignerinestimatingthewetlandplantdemandonwater

volumes.LiteraturevaluesforvariousplacesintheUnitedStatesvaryaroundthefreewater

surfacelakeevaporationvalues.EstimatingEtonlybecomesimportantwhenwetlandsare

beingdesignedandemergentvegetationcoversasignificantportionofthepondsurface.In

thesecasesconservativeestimatesoflakeevaporationshouldbecomparedtocrop-basedEt

estimatesandadecisionmade.Crop-basedEtestimatescanbeobtainedfromtypical

hydrologytextbooksorfromthewebsitesmentionedabove.Avalueofzeroshallbeassumed

forEtunlessthewetlanddesigndictatesotherwise.

Overflow(Of)Overflowisconsideredasexcessrunoff,andinwaterbalancedesignis

eithernotconsideredsincetheconcernisforaverageprecipitationvalues,orisconsidered

lostforallvolumesabovethemaximumpondstorage.|4|Obviously,forlong-termsimulations

ofrainfall-runoff,largestormswouldplayanimportantpartinponddesign.

Notes

[1]关于植物或者节肢动物的水平衡也经常被论及，他们有多种水保持机制，包括有限

渗透性的脂蜡质覆盖层。

[2]水平衡的计算可以帮助确定一个排水区域是否足够大或者是否能够在平常或极端条

件下支撑一个永久的水池。

[3]蒸发速率取决于蒸汽压的不同，而蒸汽压依次取决于温度、风、大气压力、水的纯

度、水池的形状和深度。

[4]溢流被认作多余的径流，在水平衡设计中，要么因为关心的是平均降水量，不被考

虑，要么是被作为超出最大池容量的所有容积损失。

ReadingMaterialB

WaterResourcesProtection

Waterresourcesinvolvesurfacewater,waterbelowgroundandwaterthatfallsfromthe

sky.Protectinggroundwaterresourceswillbeamajorchallengeincomingyearsbecauseof

increaseddevelopmentpressuresandwaterdemands,climatechange,andtheuncertaintyof

surfacewateravailability.

Groundwaterisahiddenresource,andtolearnmoreaboutthisresourcewehavetorely

onmorethanourfivesenses.Fortunately,wedonothavetoresorttodowsingtogainabetter

understandingofgroundwater.Groundwatermappingandmodelinghelpsusmakedecisions

abouthowtomanagewaterresourcesintermsofbothwaterqualityandwaterquantity.111

Groundwaterisoneofthenation'smostcriticalnaturalresources.ltisthelargestsource

ofusablewaterstorageintheUnitedStates,containingmorewaterthanallreservoirsand

lakescombined,excludingtheGreatLakes.Accordingtoscientists,anestimated1million

cubicmilesofgroundwaterislocatedwithinone-halfmileofthelandsurface.Onlyavery

smallpercentageofgroundwaterisaccessibleandcanbeusedforhumanactivities.Most

citiesmeettheirneedsforwaterbywithdrawingitfromthenearestriver,lake,reservoir,but

manydependongroundwateraswell.121

WaterisalreadyinshortsupplyinmanypartsoftheUnitedStates,andthesituationis

onlygoingtogetworse.Accordingtoa1999UnitedStatesGeologicalSurvey.Groundwater

isthesourceofabout40%ofthewaterusedforpublicsupplyandprovidesdrinkingwaterfor

morethan97%oftheruralpopulationintheUnitedStates.l31Between30%and40%ofthe

waterusedfortheagriculturalindustrycomesfromgroundwater.Weneedtounderstand

groundwaterifwearegoingtocontinuetomakegooddecisionsaboutsustainablewater

resources.

Inrecentyears,peoplehavebeguntounderstandthatgroundwaterandsurfacewaterare

fundamentallyinterconnectedandareintegralcomponentsofthehydrologiccycle.

Nevertheless,mostlawsgoverninggroundwaterissuesarebasedonthisnotionthat

groundwaterandsurfacewaterhavenothingtodowitheachother.Inmostpartsofthe

country,surfacewaterisgovernedbydoctrinesofriparianlaworprior

appropriation.Groundwatertraditionallyhasbeentreatedasacommonresource,with

virtuallynorestrictionsonaccessingthewater.Ifyoucanaffordtopaysomeonetodrilla

wellandyouhappentohitwater,youcandowhateveryouwantwithit.

Theunregulatedpumpingofgroundwaterisnolongeraviableoption.Inmanypartsof

thecountry,groundwaterisbeingwithdrawnatratesthatarenosustainable,andtheresultisa

degradationofwaterqualityandquantity.14,Thewaterlevelinaquifersisbeinglowered,and

becausewekeepdiggingdeeperanddeeperwellstoaccessthewater,thewaterquantityis

furtherdepleted.Incoastalareas,intensivepumpingoffreshgroundwaterhascaused

saltwatertoseepintofreshwateraquifers.

Groundwaterisalsocriticalfortheenvironmentalhealthofrivers,wetlandsandestuaries

throughoutthecountry.Groundwaterwithdrawalscanresultinreducedflowstostreamsand

alterwetlandhydrology.Changesinstreamflowhaveimportantimplicationsfbrwaterand

floodmanagement,irrigationandplanning.

Therearehundredsofexamplesacrossthecountrywheregroundwateristhreatened.The

CaliforniaDepartmentofHealthServicesreportedin2008thatmorethan300publicsupply

sourcesandanequallylargenumberofprivatehomeownerwellswerecontaminatedand

shouldnotbeused⑸.InportionsoftheSouthwest,Northwest,andMidwest,arsenicoccers

naturallyingroundwateratlevelsthatexceeddrinkingwaterstandardsandmany

municipalitiesarenowdebatingwhethertobuildtreatmentplantsorreservoirs.Eitherwill

costhundredsofmillionsofdollars.

AccordingtotheArizonaDepartmentofEnvironmentalQuality,approximatelyone-third

ofArizonawatersystemsexceedthelevelsetfbrarsenicpoisoning.Onelong-termimpactof

the1988droughtintheMidwestisthatmanyaquiferswereoverpumpedbyfarmersseeking

tosavetheircropsandtheirwayoflife.Arkansasresidentsusegroundwatertomeet

approximately93%oftheirwaterneeds.

InmanypartsofFlorida,theexistingaquiferisnotsufficienttomeettheneedsofthe

state'sgrowingpopulationandtheneedsoftheenvironment,agriculture,andindustry.Florida

isoneoffourstatesinthecountrythatusesmoregroundwaterthansurfacewater.

TheGroundWaterProtectionCouncil(2007)hasdefinedabroadvisionofwhatitwould

taketomaintainasustainablesourceofgroundwater.Itwrotethatthenationneedsto:

Continuetoconductresearchandprovideinfbrmation-atascalethatisusefultostatesand

localentities-aboutsuchmattersasthesafe,orsustainable,yieldofaquifers(andmethodsfbr

determiningthatyield);water-usedata;anddelineatingboundariesandwaterbudgetsof

three-dimensionalwatersheds,includingscientificallybasedandcost-effectivemethodsof

quantifyinginteractionsbetweengroundwaterandsurfacewater.

Notes

[1]地下水的测绘和模型帮助我们确定在水质和水量两个方面怎样管理水资源。

[2]许多城市从最近的河流、湖泊，或者水库中抽水满足他们的需求，但是也有很多是

依赖地下水的。

[3]依据美国1999年的地质调查，公共供水中的40%是来自于地下水，地下水为97%

的美国农村人口提供饮用水。

[4]国内许多地方，地下水的抽取速度是不可持续的，结果是水质和水量的下降。

[5]加利福尼亚卫生服务部门2008年报告：超过300个公共供应来源和同样大数量的私

人水井被污染了并且不能再使用。

Unit2WaterLegislationandRegulation

Theaimofnationaldrinking-waterlawsandstandardsshouldbetoensurethatthe

consumerenjoyssafepotablewater,nottoshutdowndeficientwatersupplies.

Effectivecontrolofdrinking-waterqualityissupportedideallybyadequatelegislation,

standardsandcodesandtheirenforcement.Theprecisenatureofthelegislationineach

countrywilldependonnational,constitutionalandotherconsiderations.Itwillgenerally

outlinetheresponsibilityandauthorityofanumberofagenciesanddescribetherelationship

betweenthem,aswellasestablishbasicpolicyprinciples(e.g.,watersuppliedfor

drinking-watershouldbesafe).Thenationalregulations,adjustedasnecessary,shouldbe

applicabletoallwatersupplies.Thiswouldnormallyembodydifferentapproachesto

situationswhereformalresponsibilityfbrdrinkingwaterqualityisassignedtoadefined

entityandsituationswherecommunitymanagementprevails.111

Legislationshouldmakeprovisionfbrtheestablishmentandamendmentof

drinking-waterqualitystandardsandguidelines,aswellasfbrtheestablishmentof

regulationsforthedevelopmentandprotectionofdrinking-watersourcesa