Development of a coupled quantity-quality-environment water allocation model applying the optimization-simulation method

A river basin usually provides water for multiagent. Imperfect coordination mechanisms among these agents, however, usually lead to serious water shortage, pollution, and ecological degradation. Therefore, it is vital to conduct research on allocating different kinds of water resources among multiagent including the water quantity agent, water quality agent and environment agent within a river basin. This paper proposes an optimization-simulation method that takes into consideration engineering measures, including water transfer projects, reservoirs, canal heads, and pump stations; multi-water resources such as local surface water, transferred water, groundwater, and reused sewage; and multiagent for remitting serious water problems. In the proposed optimization-simulation method, the groundwater and reused sewage are first allocated according to the water resources allocation simulation module (Module 1). Then, local surface and transferred water are allocated based on the water resources allocation optimization module (Module 2), which comprises water quantity, water quality and environment agents' objectives based on synergism. Finally, the instream water quality is simulated according to the water quality simulation module (Module 3). Results show that, compared to the current situation, the water quantity and environment agent guarantee rates can satisfy the design requirements in the planning year of 2020. The regulated instream water quality is also improved; although, it still remains relatively poor. Water quality in the downstream is worse than that in the upstream. In addition, the water quality shows a positive correlation with the instream streamflow. These results certify the proposed optimization-simulation method can provide support for efficacious multiagent water resources allocation. (C) 2018 Elsevier Ltd. All rights reserved.