Improving regional water scarcity footprint characterization factors of an available water remaining (AWARE) method

Increasing water demand and decreasing freshwater availability in an area can cause water scarcity leading to damage to human health, ecosystem quality, and natural resources. Many countries around the world, including Thailand, have recognized the importance of this problem. The available water remaining (AWARE) characterization model provides water scarcity footprint characterization factors (WSF CFs) for assessing the WSF of products. AWARE CFs were prepared from WaterGAP model's data and are available in watershed and country levels. They were not provided for specific areas and could not accurately explain water scarcity situations in certain regions, potentially leading to inappropriate water management. This work calculates the annual and monthly local CFs from local data in the Chao Phraya watershed in Thailand. The monthly local CFs with local environmental water requirement (EWR) calculations ranged from 0.10 to 100. The mean difference between AWARE CFs and local CFs was statistically significant. The most sensitive parameters for local CFs in the dry season were water availability (WA) and agricultural water consumption and that in the wet season was WA. The weighting of AWARE CFs by each type of water consumption and an aggregate of AWARE CFs for product production has been recommended for WSF assessment. The AWARE methodology was modified to assess the individual water scarcity of each water user based on the order of priority. For the Chao Phraya watershed, the ranges of the monthly local individual CFs using local EWR calculations of domestic, environment, livestock, agriculture, and industry were 0.10–0.33, 0.10–0.37, 0.10–0.37, 0.10–100, and 0.10–100, respectively. This assessment of individual water scarcity is helpful for prioritizing the level and timing of water use to minimize their impacts on critical water scarcity.