경천가뭄지역 농업용수 공급량의 수로손실 분석

Abstract

The purpose of this study is to estimate the channel water loss of agricultural water supply in the command areas belong to Yechon irrigation channelof Gyeongcheon reservoir located Mungyeong-si, which area experienced a severe drought in 2015. The channel water loss was estimated bycomparison of the irrigation water requirements (IWR) and agricultural water supply of the field data from 2012 to 2015. Further analysis wasconducted to define the conveyance loss estimated based on the leakage holes and illegal pumping spots investigated through the field survey, andthe distribution loss obtained by subtracting conveyance loss from the channel water loss. The annual rainfall decreased gradually, but the contributionof effective rainfall, available rain water to crop, increased to IWR during the study period. These phenomena resulted in the increase of agriculturalwater supply, and hence made greater the channel water loss simultaneously. The average channel water losses estimated as 36.8 % with 7.1 % ofthe conveyance loss and 29.7 % of distribution loss respectively. The distribution loss seems to be related to total number of rainy days, and irrigationschedules, while the conveyance loss was caused by irrigation channel aging conditions and illegal intake problems. In order to achieve sustainableagricultural water resources, the channel water loss needs to be reduced through the restoration of aged irrigation facilities and effective watermanagements in the fields.