In view of the requirements of water resources protection in the reservoir area after the completion of the Datengxia Gorge Water Conservancy Project, water environment and water ecology challenges in water resources protection, including water quality pollution risks and eutrophication trends, were analyzed based on investigation of the environmental characteristics and ecological function positioning of the reservoir area, and countermeasures, including the implementation of water ecological protection measures, timely implementation of follow-up monitoring and post-evaluation, and integration of the reservoir area water ecological space into the territorial space planning control system, were put forward. Following the water control policy of giving priority to water saving, spatial balance, systematic management, and two-handed efforts, a water resources protection control index system was proposed. According to the idea that systematic governance of mountains, rivers, forests, fields, lakes, and grasslands should strengthen the comprehensive remediation of the watershed and promote ecosystem restoration, an overall layout of the “one belt, one circle” plan for water resources protection was proposed, with the “one belt” protection strategy focusing on canyon water quality protection and sensitive target water ecology protection, and the “one circle” protection strategy focusing on non-point source pollution control, ecological scheduling, and watershed monitoring and management.