三峡工程运行后洞庭湖区饮用水的安全现状及影响因素分析

 为了解湖区饮用水安全情形，以洞庭湖区为例，利用洞庭湖入出湖径流量、水位和水质等监测数据，运用对比分析、数理统计和水质评价模型等分析方法，分析了湖区饮水安全现状，并从水量和水质两方面重点研究三峡工程蓄水运行对湖区饮水安全的影响，梳理了湖区饮水安全方面存在的问题，探讨了影响湖区饮水安全的原因。结果表明：洞庭湖地表水和地下水受到严重污染，存在重金属超标等问题，人畜饮水安全受到威胁；特别是三峡工程蓄水运行后，荆江三口入湖水量锐减，三口分流总量已下降为475×10⁸ m³/a，缩减幅度达52%；湖区降水持续偏少也加剧了湖区的旱情，降水量较历年同期偏少52%。为此，提出了保障湖区饮水安全的对策和治理措施：应优化水资源配置，加强水资源保护，做到取水与治污相结合；加大湖区饮用水工程建设力度，加强饮用水安全管理。

The present situation in Dongting Lake Basin after the operation of Three Gorges Project and its influencing factor of drinking water safety

The regional economy development is restricted by the supply of high-quality water resource. As an important source of drinking water and fresh water reserve for people's livelihood in the Dongting Lake Basin, the water quality of Dongting Lake directly affects people's health. To grasp the drinking water security situation in the Dongting Lake Basin, we take the advantage of monitoring data such as runoff, level and quality of Dongting Lake water both into and out of the lake, and use comparative analysis, mathematical statistics and water quality evaluation model, as well as other analytical methods to study the current situation of drinking water safety and the impact of the operation of the Three Gorges Project on drinking water safety in the Basin in terms of water quantity and quality. Aiming at the problems existing in drinking water safety, we discuss the reasons for the safety of drinking water in the Basin. We show that the surface water and groundwater in Dongting Lake are seriously polluted and that there are some problems such as excessive heavy metal and threat of drinking water for people and animals. Especially after the operation of the Three Gorges Project, the water into the lake of the Three Outlets of Jingjiang River drops sharply, and the total diversion of Three Outlets has decreased to 475×10⁸m³/a, a reduction of 52%; continuous lowrainfall in the Basin also exacerbates the drought situation, with precipitation dropping by 52% over the same period of the previous year. Finally, we put forward countermeasures and measures to ensure the safety of drinking water in the Basin. First, allocation of water resources should be optimized and the protection of water resources should be strengthened so that the combination of water abstraction and pollution control can be strengthened. Then, the construction of drinking water projects should be increased in the Basin and the management of drinking water safety should be improved. Last but not the least, a basis for solving drinking water safety problem in the Basin is urgent, which may play an active role in ensuring the harmonious and stable development of the ecological economic zone of Dongting Lake.