在过去没有自来水的时候，中国人需要去河边挑水或是用水泵抽取地下水来饮用，这两种方式都不方便，所以家中常备一个大缸，用来储水。而近年来，水污染越来越严重，偶尔会出现断水现象，于是储水变得不可避免，但是如果方法不当，储存的水很容易变质。
Manypeoplestorewaterforemergencies.Thisisespeciallytrueinruralareaswheredrinkingwatercomesfromprivatewells.Thesewellsareuselessunlessthereispowertorunthepump.Ifyouaretryingtostorewatersafely,today'squestionisagreatone!
Itturnsoutthattherearetwowaysforwatertogobad.Youcaneasilydemonstratethefirstwaybyfillingabucketwithtapwaterandleavingitonthebackporchforseveraldays.Afteraboutaweek,youwillfindthatthewaterinthebucketcontainsmosquitolarvae,algaeandvariousotherlifeforms,noneofwhichyouwouldwanttodrink.Fromthisexperiment,youcaneasilydecidethatstoringwaterinanopencontainerisabadideaunlessyouhaveaplantopurifyitwhenyouneedtodrinkit.Storingwaterinaclosedcontainerworksnobetterifthewaterthatyouplaceinthecontaineriscontaminatedinsomewaywithbacteriaoralgae.Youneedtoputpurewaterinacleancontainerandthenprocessitinsomewaytoeliminatebacterialcontamination.Youcanprocessthewaterwithheatjustlikeyoudowhencanning,oruseachemicallikechlorineoriodine.
Thesecondwayforwatertobecomeunfitfordrinkingisforsomethingtoleakoutofthecontainerintothewater.Asanextremeexample,imaginewhatwouldhappenifyouweretostorewaterinaleadcontainer.Leadwouldleakintothewaterandmakeitpoisonous.Thecontaineryouuseneedstobemadefromaspecialmaterial,calledfoodgrade,inordertoavoidleakingproblems.Glass,stainlesssteelandsomeplasticsarefoodgrade.
Oneeasywaytostorewateristobuypurifieddrinkingwateringallonplasticjugsatthegrocerystore.Thiswaterisinexpensive,freeofbacterialcontaminationandissealedinafood-gradecontainer.
larvae：（昆虫）幼虫
algae：藻类
chlorine：氯
iodine：碘,碘酒
foodgrade：食品标准
gallon：加仑