Estimation and application of the water resources distribution using the Water Accounting Plus: A case study of the Kherlen River basin

Abstract

It is crucial to assess water resources in a basin level to have observational data and measurements related to the water, its data processing and reporting. To present water resources in the spatial way is valuable information for the stakeholders including decision makers, water users and managers. However, not every river basin has adequate measurement network and spatially estimating water resources is challenging. Therefore, we applied the water accounting plus to estimate water resources as a spatial representation for the Kherlen river basin for the period of 2005-2020. Water Accounting Plus is a method to analyze water resources considering different land uses using the open-source remote sensing datasets. For this study, GPM and SSEBop datasets were used for the basin and validated with ground measurement data from six meteorological stations. Based on WA+ outputs, Sheet and Sheet 2 were developed for the Kherlen river basin in high and low water years. In high water year, the basin receives precipitated water as 35.3 km3 and its 23.3 km3 are lost by evapotranspiration and 1.9 km3 water is outflow as a runoff. For the low water year, 22.8 km3 water fall as a precipitation at the basin and only 0.7 km3 is outflow as a runoff of Kherlen river. In addition, we analyzed how spatial maps of water resources can be used for the water resources planning such as the Bag-level livestock water supply in Dornod province, which overlaps the Kherlen river basin. Of the 23 Bags in Dornod province, 11 have not enough water availability for the livestock. It noted that WA+ was a method of analyzing water resource and the. Further research is needed to validate remote sensing data with more ground data and will refine the groundwater resources estimation.