RECHARGEWhat is recharge?Deep drainage or deep percolation.Addition of surface water to zone of saturation.Can be natural as part of the hydrologic cycle known as natural recharge.Can be artifcial by altering natural conditions.Where and when does it occur?What is its importance and relevance?Sustainable groundwater management (relationship of volume-rate.!educes surface runo".#$cess salts that accumulate in the root zone to deeper soil layers.Two Tpes o! Recharge"atural Recharge%atural movement from precipitatesArti#cial Recharge&looding'n(ection wells'nduced recharge from bodies of water$looding)hismethodissuitableforrelatively*at region where water can be spread as a thin layer.+aterisdistributedovertheregion usingadistributionsystem.)hismethod canachievehigherrateofinfltrationina region having thin vegetation cover or sand soil cover. %n&ection Wells!echargewellsareusedtorechargewater directlytothea,uifer.)hesearesimilarto pumpingwellsandre,uiresawatersupply system.%nduced Recharge !rom 'odies o! Water'tisanindirectmethodofartifcial recharge.'nthismethodwaterispumped fromthea,uiferhydraulicallyconnectedto the surface water sources like stream- river or lake. .ue to pumping- a reverse gradient is formed and water from the surface water sourceentersintothea,uiferandthusthe a,uifer is recharged . %nduced Recharge !rom 'odies o! WaterEstimation o! Recharge/roundwater level water *uctuation methodGroundwater (evel $luctuation )ethod/roundwater level *uctuations over a period is used.Calculations are based on the +0#.)o ac,uire total annual recharge- both monsoon months and non-monsoon months records are then taken and added.)he specifc yield for various hydro-geologic conditions in a country is estimated.Groundwater (evel $luctuation )ethod+here12 Specifc 3ield2 /ross recharge due to rainfall and other sources2 /ross water draft 0 2 0ase *ow into the stream from the area 2 !echarge from the stream into the groundwater body' 2 %et ground *ow of water into the area across the boundaryGroundwater Resource5easures the annual groundwater resource which is available for irrigation- domestic and industrial uses..epends on in*ows and out*ows.#$pressed in +0#.Groundwater Resource +here12 all forms of recharge such as precipitation- infltration from lakes- streams and canals6 and artifcial recharge in the basin. net discharge of groundwater from the basinand includes pumping- surface out*ows- seepage into lakes and rivers and evapotranspiration. 2 change in the groundwater storage overa time.