Appraisal of quality of irrigation water of Canning Blocks of West Bengal

Abstract

Irrigation water samples (92 and 79) collected trom various sources of Canning (I and II blocks respectively) during 1991-94 were classified on the basis of electrical conductivity (EC) and sodium adsoiption ratio (SAR). There was good rise in salinity and Na²⁺ Mg²⁺ Ca²⁺, Cl^- and B concenlrations of irrigation waters, with change in the time of collection trom Decernber-January to April-May. Water of each class strongly influenced the salinity of the irrigated soils except class I water having EC <= 1.0 dS/m and SAR <10 (m mol/litre)sqrt. using the threshold salt concentration
limit of <=1 to 1.3 mg/litre (EC <=1.5-2.3 dS/m) of waters and its influences on corresponding soils, 77 and 47% water in Canning I and II blocks, respectively were found suitable for irrigation in December-Januray and; 35 and 25% in April-May.