Principle of Design Flow Selection in Water and Environment Planning in the Haihe Basin

摘要

As the most rivers are controlled by reservoirs, and dams throughout the Haihe basin, the design flow of the rivers more reflect artificial control. In view of the problem that required flow for the downstream adopted by reservoir engineering is the minimum discharge flow (characterized by minimum ecological flow or design flow in dry season), the paper points out the problem that the existing design conception that could enlarge the risk to several months after the reservoir running, and the problem that the environment capacity of accumulative pollutants decline, from the perspective of maintaining the environment capacity for oxygen consuming pollutants, toxics, and carcinogens. The paper proposed the principle of adjusting the design flow in the condition where there exists drinking water source downstream, proposed three indicators for long term design flow in order to meet the requirement of ecology and environment goal of the river and sea, and to improve the under-protecting problem for the river and sea in the present situation.