Effectiveness of concrete linings of irrigation canals in control of seepage losses in Hamadan convenience

Different kinds of irrigation canal lining materials have different durability based on climatic conditions. Therefore its necessary that in different area all various lining are evaluated and suitable lining be selected for decrease seepage loss and optimum usage from water resource. The aim of this research was to study effect of concrete lining to reduce of water seepage loss in the main irrigation earth canals that serves the irrigated area on Hamadan province. Total length of concrete-lined irrigation canals in this province is 500 km. 12 main lined and unlined canals with total length of 26 km were chosen to study in this area. Water seepage in these canals was measured by the inflow-outflow method. While water velocity was determined using a current-meter. The water seepage loss at unlined-canals was between 1.32 and 3.06 m3m-2day-1. The average seepage loss was 2.39 m3m-2day-1 equal to 16.4% in 1Km. The water seepage loss at concrete lined-canals was between 0.55 and 2.40 m3m-2day-1. The average seepage loss was 1.74 m3m-2day-1 equal to 8.2% in 1Km. Based on statical analysis, there was no significiant difference for seepage loss between lined and unlined canals typs. d.