Abstract Sinnar Dam supply water to Gezira Irrigation Scheme according to water indenting from Scheme Divisions which collected from Gezira and Managil branches at Wad alNaw (kilo 57 ) and sent to Sinnar Dam as final crop water requirets( CWR ) for agiven period . In this Study a comparison of levels in Gezira and Managil main canals in specific month every 10 years in period from 1980 to 2019. Results shows that in Gezira main canal level was increased in range (1.2 to 1. 52 m), while Managil main canal increased in range (0.56 to 0.75 m) Also Study for actual Sinnar Dam water release to Gezira Scheme for period 1970 to 2019 shows that % age of water released from Dam to CWR for irrigated cultivated area varies from 72% to 112% for the period from 1970 to 1996 ( average 86% ) while it was varies from 97% to 172% from 1997 to 2019 ( average135 %), while in the same period there was down decreasing in related cultivation irrigated area .