PERFORMANCEEVALUATIONANDIMPACTASSESSMENTOF MEKI-ZIWAYIRRIGATIONSCHEMEINTHE CENTRALRIFTVALLEY

Abstract

Knowledgeoftheperformanceofexistingirrigationschemeshelpstoidentify alternativesthatmaybebotheffectiveandfeasibleinimprovingsystem performance.Thepurposeofthisstudywastoevaluatetheperformanceofthe Meki-Ziwayirrigationschemeusingdifferentperformanceindicators (application,storage,distribution,overallirrigationefficienciesandagricultural andwaterusecomparativeperformanceindicators)usedasatool.Thestudy hasbeenfocusedonidentifyingthebenefitsandconstraintsoftechnical,socioeconomicandenvironmentalaspectsoftheirrigationschemeInorderto undertakethisresearchprimaryandsecondarydatawerecollected.Primary dataincludecanalwaterflowmeasurement,measurementofirrigationwater appliedtothreefarmersfields(fromthehead,middleandtailendwaterusers) usingvolumetricmethod,moisturecontentdeterminationofthesoilandsemistructuredquestionnairesurveyandgroupdiscussion.Secondarydatasuchas yearlypumpoperatinghouryieldperyear,areairrigatedpercropperyear,farm gatepriceofcrops,andotherstudieslikedesigndocumentswerecollected. Theresultindicatedthatapplicationandstorageefficiencyoftheirrigation projectwere48.71%and61.74%.Distributionlosses,whichindicatesthe amountofwaterlostduringtransportationofwaterfromthesourcetothefield canalis45.55%.Theoverallirrigationefficiencyoftheschemeis25.06%. Fromtheanalysesofthecomparativeperformanceindicators,theresultofthe• ratiosofRWSandRISrangesfrom0.92to3.35and0.63to6.68.Outputper croppedareaandperunitcommandareaoftheseasonsvarybetween 24,412.24birr/hato3,733.10birr/haand273.97birr/hato3579.70birr/ha respectively.Theoutputperunitirrigationsupplyrangesfrom0.17to2.49 birr/m^.Outputperwaterconsumedvariesfrom0.62to4.41birrperm^.The findingofquestionnairesurveyshowsthattherearemanytechnical, management,andinstitutionalproblemsthatconstrainirrigationperformances. Althoughirrigationiscrucialinincreasingfoodproduction;thegovernmenthas xu founditincreasingdifficulttofinancethecostofirrigationoperationand management.Thishasledtorapiddeteriorationofinfrastructure,poor managementandsubsequentwastageofwaterandadvancingwaterlogging andsalinity.Poorsystemperformanceandthegovernmentinabilitytodo somethingaboutithaveretardedtheeffortstoincreasefarmers'participationin irrigation.Therefore,farmer'sinvolvementinirrigationplanningshouldbe consideredfromthebeginning.