Analysis of physical and non-physical factors associated with individual water consumption using a hierarchical linear model before and after an earthquake in a region with insufficient water supply

In regions suffering from water scarcity, residents commonly employ several coping strategies such as the use of multiple water sources, water storage and water sharing and borrowing. This study applies a hierarchical linear regression model to investigate the physical (i.e. water source and supply time) and non-physical (i.e. number of families, wealth status, education for household head, house ownership, water treatment and community involvement) factors associated with individual water consumption throughout the Kathmandu Valley, Nepal. During the baseline period (dry season before the 2015 Gorkha earthquake), the average water consumption was 91 litre/capita/day (LPCD) but there was a regional disparity in water consumption, ranging from 16 to 158 LPCD. The statistical analysis indicated that households using many water sources consumed more water regardless of the supply area even in an emergency. In addition, households with many family members used less water per person. During emergencies, households participating in the local community were found to consume more water than households not participating in the community, especially when the water being used was managed by the community.