Abstract:
Thisstudyhasbeencarriedoutinth eLakeBesekacatchment,locate dsom e195
kmnortheastofAddisAbaba.Themainobjectiveotthi sstudyistostudyth e
effectotth enewlyestablishedirrigatio nprojectonth eleve lotLakeBeseka.It
alsoinclude sth ewaterbalanceotth elak eanditscatchment.
Themethodologyfollowe disconventionalwaterbalanceassessment,irrigatio n
schedulesandetticiencyinrelatio ntolak elevel sandgroundwatermodeling.
RS/GIShavealsobeenused.
Thestudytargete donth eeffectotnewlyimplemente dFentaleIrrigatio nonLake
Besekawaterleve levaluatingrespons eotth elak et oth eirrigatio nactivitiesnear
thelak earea.Thestudyshedsligh tonth enatureotth eirrigatio nonth e
subsequentGroundwatermovementthroug hth eaquifer.
Theresulto tth estudyshowstha tth elak eismuchaffectedbysurpluswater
fromtheirrigatio nprojects.Duet oFentaleirrigatio nprojectth eGroundwaterhas
beenincreasin g37.07momperannumupto1998.Thisshow stha tth elak e
waterleve lwasrisingat0.15mperyearwithcorrespondingstoragechangeot
5.38momperannum .Aftertullimplementatio nofth eFentaleirrigatio nproject
underexistingirrigatio netticiencyth enetgroundwaterinflo wwillincreas efro m
48.34to61.07momannually,Thisshow stha tth elak ewaterleve lwillriseata
rateot0.19mannuallywithth ecorrespondingstoragechang eot9.05mem.
Thereforeth elak ewaterleve lreache s952.95mwithin11to12years(2020 -2021).Atthisstagth elak ewaterspillst oth eAwashRiverthroug hth esaddle
pointlocatedatanelevationot952.95m.a.s.l .
Thisstudyhascertainlimitation .Theamountotpumpedwaterhasnotbeen
properlyrecorded .Groundwaterleve lmonitoringhasnotcarriedoutperiodically
includingth eirrigatio nwaterinth edifferentfarm sandSystematicwaterquality
monitoringotth eAwashRiver,th elak eandspringstha trelate dth eirrigatio n
activitywerenotconductedregularly .
