HAN Songjun1, 2, WANG Shaoli1, 2, CHEN Haorui1, 2

1. Department of Irrigation and Drainage, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
2. National Center of Efficient Irrigation Engineering and Technology Research, Bejing 100048, China

Abstract: The water balance of Huinong Irrigation District from 2007 to 2011 was simulated using the runoff-evaporation hydrological model, and the impacts of drainage water reuse were evaluated. The water balance in the study area was influenced by the irrigation water withdrawal from the Yellow River, precipitation, drainage water reuse and groundwater exploitation. For the up- and down-streams, the drainage water reuse is more than 30 % of the total inflow into the irrigated area. Taking the sub-regions 2 and 7 as examples, the impact of drainage water reuse on the water balance was analyzed according to the comparisons with two scenarios with decreased drainage water reuse. The simulated crop evapotranspiration was reduced by 12.6 % and 7.7 % respectivety under the scenario with no drainage water reuse. The changes mainly happened from June to August. The simulated average groundwater table fell by 0.27 m and 0.54 m for sub-region 2, and 0.22 m and 0.50 m for sub-region 7, under the scenario with 50 % of current drainage water reuse and the scenario with no drainage water reuse, respectively. The study indicates that the drainage water reuse has important impact on the water balance in Huinong Irrigation District.

Key words: Huinong Irrigation District; runoff-evaporation hydrological model; water balance; drainage water reuse

Published in: Journal of China Institute of Water Resources and Hydropower Research, Vol. 13, No. 3, June 2015