Hydrological modelling for integrated water resources management in a changing climate

• Main Author: Abbas, Salam A. A.
• Other Authors: Xuan, Yunqing
• Published: Swansea University 2018
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.752398

Hydrological models are a simplified representation of hydrological processes and can be very used for the water resources assessment and gain an integral view of the water resources status for integrated water resources management IWRM. Furthermore, they can be used to investigate the possible impacts and trends resulting from different types of scenarios, such as climate change impact studies. Accordingly, with IWRM as the future application, the primary objectives of this study is to use a hydrological model, SWAT for the modelling of a highly-regulated river basin through the physical flow control (reservoirs release in the upstream region), the Dee River Watershed in the United Kingdom. Moreover, an essential aspect of model input uncertainty, i.e. precipitation is investigated on the simulated streamflow where different methods of rainfall pre-processing are used. Furthermore, a quantile regression method is employed for analysing the long-term historical trend of rainfall, river flow and catchment water yields focusing on the patterns of the data close to 'extreme' regimes, to link them to the events of interests for the climate change impact studies. Additionally, a reliable simulation of both land surface and groundwater hydrological processes is a far important step for IWRM. One way to achieve such purpose is the coupling of surface and groundwater models. The land surface model (SWAT) is coupled with the groundwater flow model (MODFLOW) to improve the baseflow simulation of the SWAT standalone in the study area. Another critical aspect of this study is the investigation of parameter uncertainty of the coupled SWAT-MODFLOW. Finally, the climate projection data from the CMIP5 project is utilised with allocation model, Water Evaluation and Planning software WEAP to address climate change impact for future scenarios on water resources. All presented models performed well in demonstrating the study conditions, as indicated by the statistical performance. The research approach of the integrated models can generally apply to any catchment and inspired by the need of considering all aspects related to hydrological models for IWRM to bridge the gap of between stakeholder involvement and natural hydrological processes in building and applying integrated models to ensure acceptability and application in decision-making for IWRM.