Decrease of both river flow and quality aggravates water crisis in North China: a typical example of the upper Yongding River watershed

• Published in: Environmental monitoring and assessment Vol. 192; no. 7; p. 421
• Main Authors: Dai, Dan, Xu, Xiangqin, Sun, Mingdong, Hao, Chenlin, Lv, Xubo, Lei, Kun
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 08.06.2020; Springer Nature B.V
• Subjects: Arid regions; Arid zones; Atmospheric Protection/Air Quality Control/Air Pollution; Chemical oxygen demand; Crises; Degradation; Earth and Environmental Science; Ecology; Ecotoxicology; Environment; Environmental Management; Environmental monitoring; Environmental science; Eutrophic reservoirs; Eutrophication; Food safety; Hydrologic studies; Hydrology; Intensive farming; Irrigation; Man-induced effects; Monitoring/Environmental Analysis; Nitrogen; Oxygen; Pollutant load; Pollutants; Pollution load; Reservoir storage; Reservoirs; River flow; River water; Rivers; Salinization; Semi arid areas; Semiarid lands; Semiarid zones; Stream flow; Wastewater discharges; Wastewater treatment; Water consumption; Water crises; Water management; Water pollution; Water quality; Water resources; Water shortages; Watersheds; China; River flow; Yongding River; Pollutant loads; Water quality; Water crisis
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-020-08371-6

Due to unevenly distributed water resources, semi-arid regions are particularly prone to severe water shortage and quality degradation. In this study, based on long-term hydrological database (1935–2015), and the latest available water quality data sets (2011–2016), we analyzed the water crisis and its driving forces in the upper Yongding River watershed, a typical water shortage area in North China. The results showed that human induced excessive water consumption is responsible for the significantly decreased river flow over the past eight decades. Although the capacity of the watershed wastewater treatment has improved, current water quality does not meet the requirements of the national water management goals, because of the excessive nitrogen and COD Cr (chemical oxygen demand), which mainly come from the wastewater and feedlots discharge. Due to the decreased river flow, current Yongding River is unable to dilute and assimilate pollutions. The analysis of river pollutant load illustrated that more than 60 % of the nitrogen in the river water system is diverted for reservoir storage, and more than 50 % of the COD Cr and TP are diverted for irrigation, thereby, increasing the risk of reservoirs eutrophication and threatening food safety. Besides, the high Cl − (388.2 ± 322.5 mg/L) and SO 4 2− (470.6 ± 357.7 mg/L) imply that the upper river water are not suitable for drinking and irrigation purposes, and a potential risk of salinization if the river flow continues to decrease. We conclude that water resources over extraction and quality degradation are the main driving factors of the Yongding River water crisis.