A study on sediment avoidance diversion and the coordinated dispatch of water and sediment at an injection-water supply project on a sediment-laden river

Abstract

Rivers in the northwestern region of China have a high sediment content, and the construction of reservoirs on these rivers must address the problem of sedimentation that results in a loss of reservoir capacity. In this study, the YZD (Yazidang) reservoir was considered as a typical case, to address the problem of sedimentation in injection-type water supply reservoirs in Northwest China. The temporal and spatial characteristics of the sediment in this water diversion project were analyzed based on available 46-year water and sediment data. The concept of 'sediment avoidance diversion' was proposed, which reduces the entry of sediment into the reservoir. A one-dimensional numerical model for water-sediment coupling was established, and the characteristics of water-sediment erosion and deposition for different operational modes were analyzed. The results show that during a period of high sediment content, large-scale siltation occurs in a water diversion channel. To alleviate sediment deposition in a diversion channel, two control strategies for mitigating siltation were formulated. Considering the pros and cons of these control strategies, a reasonable water-sediment joint operation plan has been proposed to extend the service life of the YZD reservoir. This research provides a theoretical basis for sedimentation treatment and control of similar reservoirs.

Revealing the changes in water footprint at the provincial level and their drivers in the Yellow River Basin, China

“…Among them, Ningxia had the highest per capita WF with 760.8 m 3 and 762.4 m 3 in 2012 and 2017, respectively. In addition, Qinghai Province, which is located in Northwest China, had the lowest WF but also a high per capita WF because of the vastness of the region and its sparse population (Li et al 2021, Song et al 2022b. Henan and Shandong, provinces with large populations in China, had the lowest per capita WF of 180.9 m 3 and 193.1 m 3 in 2012 and 2017, respectively, with less than onethird of Ningxia's per capita WF.…”

Managed diversion lead time effects on flood response in a tidal freshwater river

“…The computational efficiency of 1D hydraulic models also lends well to the evaluation of numerous alternative scenarios such as those involved with uncertainty analysis. Moreover, Li et al (2021) utilized a 1D hydraulic approach to quantify the effects of different operational modes on a sediment avoidance diversion aimed at reducing the sedimentation potential of reservoirs. And while advancements in hydraulic modeling and flood forecasting capabilities remain active areas of research (Jain et al, 2018; Lin et al, 2022), the impacts of managed river diversions, and operational lead times on downstream residual flood risks in receiving waters have been relatively understudied (Wang et al, 2019).…”