丹江口水库是南水北调中线工程水源地。通水以来,工程持续安全平稳运行。然而,由于丹江口水库面积大,范围广,涉及陕西、河南和湖北省3省,在水源地保护和管理方面仍存在亟需解决的问题,包括:①水库管理薄弱,如水库管理设施缺乏、水库保护和管理经费尚无渠道落实、消落区管理难度大等;②部分入库支流水质难以达标及入库支流总氮负荷高,如2017—2018年神定河和泗河入库断面水质仍为Ⅴ类甚至劣Ⅴ类,入库支流总氮浓度在2~10 mg/L之间;③中线水源地保护和管理的体制和机制仍未明确,相关法律法规尚不健全。针对水源地保护和管理中存在的突出问题,提出建设必要的水库管理设施和核增水库保护和管理经费,规范消落区的保护和利用模式,明确入库支流水质改善和提升监督管理办法及总氮负荷削减措施,以及尽快制定并颁布《南水北调中线水源地保护与管理条例》等相关法规。

Danjiangkou Reservoir is the water source for the Middle Route of South-to-North Water Transfer Project. The project has been running safely and steadily since it was put into operation. However, due to the large area and wide scope of Danjiangkou Reservoir’s water source area, which involves Shaanxi, Henan and Hubei provinces, there are still some urgent management problems needed to be solved. Such problems include:(1)Management of the reservoir is weak. For example, management facilities are insufficient, funding for the protection and management lacks regular implementation, and difficulties for management of large-scale fluctuation zones after dam heightening and periodic dispatching are still challenging. (2) Water quality of some tributaries still has not reached standards and the loads of total nitrogen from tributaries are as high as 2~10 mg/L. For instance,the Shending River and Sihe River were polluted seriously, and the water quality ranked class-Ⅴ or even inferior class-Ⅴ from 2017 to 2018. (3) The system and mechanism for reservoir protection and management are still unclear, and the relevant laws and regulations are unsatisfactory. To tackle these prominent problems, we propose to build necessary management facilities, increase protection and management funding. We also put forward the standardized protection and utilization mode of water-level-fluctuation zone, clarify the supervision and management measures for water quality improvement for tributaries, and give some measures for reducing the total nitrogen load. We recommend to formulate and promulgate relevant laws and regulations, such as the Protection and Management Regulations for the Water Source Areas of the Middle Route of South-to-North Water Transfer Project as soon as possible.