Water Diversion Project Research Articles

The influence of the South-to-North Water Diversion Project on agricultural water use in the water-receiving areas

The influence of the South-to-North Water Diversion Project on agricultural water use in the water-receiving areas

Monitoring and risk analysis of surface subsidence in the Jiaozuo Goaf along the middle route of the South-to-North Water Diversion Project based on the DS-InSAR method

Monitoring and risk analysis of surface subsidence in the Jiaozuo Goaf along the middle route of the South-to-North Water Diversion Project based on the DS-InSAR method

Challenges and protection strategies of ecological environment of lakes along the Eastern Route of the South to North Water Diversion Project

Challenges and protection strategies of ecological environment of lakes along the Eastern Route of the South to North Water Diversion Project

2000–2020年丹江口水库（河南部分）水体面积数据集

Danjiangkou Reservoir serves as the water source of the South-to-North Water Diversion Project. The long-term monitoring of changes of surface water for the reservoir using the remote sensing images is of great significance in ensuring the water transfer volume of the South-to-North Water Diversion. In this study, we used multi-temporal Landsat remote sensing images to obtain a long-time series of spatial surface water datasets for Danjiangkou Reservoir (Henan ) based on Google Earth engine cloud platform through the relationship among modified Normalized Difference Water Index (mNDWI), Enhanced Vegetation Index (EVI) and Normalized Difference Vegetation Index (NDVI). This dataset includes the surface water of Danjiangkou Reservoir from 2000 to 2020. It can provide a basis for exploring the spatiotemporal changes of the surface water and ecological environment changes in Danjiangkou Reservoir.

Influence of South-to-North Water Diversion on Land Subsidence in North China Plain Revealed by Using Geodetic Measurements

As a major grain-producing region in China, the North China Plain (NCP) faces serious challenges such as water shortage and land subsidence. In late 2014, the Central Route of the South-to-North Water Diversion Project (SNWD-C) began to provide NCP with water resources. However, the effectiveness of this supply in mitigating land subsidence remains a pivotal and yet unassessed aspect. In this paper, we utilized various geodetic datasets, including the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow On (GRACE-FO), Global Navigation Satellite System (GNSS) and leveling data, to conduct a spatial-temporal analysis of the equivalent water height (EWH) and vertical ground movement in the NCP. The results reveal a noteworthy decline in EWH from 2011 to 2015, followed by a slight increase with minor fluctuations from 2015 to 2020, demonstrating a strong correlation with the water resources supplied by the SNWD-C. The GRACE-derived surface deformation rate induced by hydrological loading is estimated to be <1 mm/yr. In comparison, GNSS-derived vertical ground movements exhibit considerable regional differences during the 2011–2020 period. Substantial surface subsidence is evident in the central and eastern NCP, contrasting with a gradual uplift in the front plain of the Taihang Mountains. Three-stage leveling results indicate that the rate of subsidence in the central and eastern plains is gradually increasing with the depression area expanding from 1960 to 2010. Based on these geodetic results, it can be inferred that the SNWD-C’s operation since 2014 has effectively mitigated the reduction in terrestrial water storage in the NCP. However, land subsidence in the NCP persists, as the subsidence rate does not turn around in sync with the change in EWH following the operation of SNWD-C. Consequently, it’s necessary to maintain and enforce existing policies, including controlling groundwater exploitation and water resources supply (e.g., SNWD-C) to curtail the exacerbation of land subsidence in the NCP. Additionally, continuous monitoring of land subsidence by GRACE, GNSS, leveling and other geodetic techniques is crucial to enable timely policy adjustments based on monitoring results.

A continuation-dynamic constitution analysis approach based on digital stable marker tracing and study on simulation of ecological tidal water diversion

Water Diversion Projects have become increasingly popular in improving water quality in various water ecosystems. However, these projects also require a more comprehensive evaluation. In this study, we introduced a digital stable marker tracing module and proposed a continuation-dynamic constitution analysis approach. We applied this approach to analyze the ecological tidal water diversion in Changshu town, China. The results showed that the mean diversion water age of the Yangtze River water source was 10.80 h, the residence time of the background water source in Baimaotang was approximately 4.0 h, and the contribution of inflow water sources from tributaries accounted for 15% of discharges. The results can demonstrate practicality of our approach in quantitatively evaluating water diversion impacts and optimizing cooperative diversion projects. Furthermore, our discussion led to the design of an ecological tidal water diversion based on optimized cooperative diversion, which showed element-complementary and whole-comprehensive effects. This indicates that the ecological tidal water diversion can extend the impact of cooperative diversion. The continuation-dynamic constitution analysis approach enhances the tracing capacity of inflow constitution and enables the distinction of different time-varying distributions of each inflow constitution. Therefore, this approach holds promise as an embedded “Digital stable marker tracing” module in the model.

An Optimal Model and Application of Hydraulic Structure Regulation to Improve Water Quality in Plain River Networks

The proper dispatching of hydraulic structures in water diversion projects is a desirable way to maximize project benefits. This study aims to provide a reliable, optimal scheduling model for hydraulic engineering to improve the regional water environment. We proposed an improved gravitational search algorithm (IPSOGSA) based on multi-strategy hybrid technology to solve this practical problem. The opposition-based learning strategy, elite mutation strategy, local search strategy, and co-evolution strategies were employed to balance the exploration and exploitation of the algorithm through the adaptive evolution of the elite group. Compared with several other algorithms, the preponderance of the proposed algorithm in single-objective optimization problems was demonstrated. We combined the water quality mechanism model, an artificial neural network (ANN), and the proposed algorithm to establish the optimal scheduling model for hydraulic structures. The backpropagation neural network (IGSA-BPNN) trained by the improved algorithm has a high accuracy, with a coefficient of determination (R2) over 0.95. Compared to the two traditional algorithms, the IGSA-BPNN model was, respectively, improved by 1.5% and 0.9% on R2 in the train dataset, and 1.1% and 1.5% in the test dataset. The optimal scheduling model for hydraulic structures led to a reduction of 46~69% in total power consumption while achieving the water quality objectives. With the lowest cost scheme in practice, the proposed intelligent scheduling model is recommended for water diversion projects in plain river networks.

Application of eco-compensation to control transboundary water pollution in water diversion projects: The case of the Heihe River transfer project in China

Controlling transboundary water pollution is particularly crucial for the sustainable development of diversion basins, while eco-compensation is an essential incentive for multistakeholder transboundary water pollution control. Considering the dynamics of the various actors' pollution control behavior in the Heihe River water transfer project and utilizing differential game theory, we construct a baseline strategy, a horizontal eco-compensation strategy, and an incentive coordination strategy under scenarios with and without authority incentives. The corresponding equilibrium solutions are then determined, and comparisons are made between the payoffs of the players in the six different structures, thus defining the optimal scenario for the different programs. In the case of the largest ecological water transfer project of the Heihe River in Northwest China, according to the research findings, (1) when eco-compensation is funded through a single source, incentive coordination scenarios can contribute effectively to water pollution control instituted by the main participants in water diversion projects; when multiple financing sources are available, horizontal ecological compensation scenarios are more compatible with the individual interests of local municipalities to improve the water quality environment. (2) Water-receiving cities voluntarily eco-compensate for water-supplying cities, and this incentive structure for eco-compensation facilitates a significant improvement in the effectiveness of water pollution control and therefore the harmonious promotion of sustainable economic and environmental development in eco-fragile areas. (3) Water transfer projects, for which the two participants are at widely.different levels of development and the environment is inherently fragile, can facilitate, via an eco-compensation mechanism that combines horizontal and vertical scenarios, sustainable development-oriented policies for eco-compensation systems in which the authority participates as a third-party game player. The research supports the establishment of policies for the governance of the transboundary water diversion project basins to address conflicts in water pollution management.

Evaluation of sustainable livelihood of reservoir resettlement based on the fuzzy matter-element model

Introduction: The study of sustainable livelihoods for reservoir resettlers is of great significance for consolidating the poverty alleviation achievements of China and promoting the realization of the major strategy of China’s rural revitalization.Methods: On the basis of the Sustainable Livelihood Analysis Framework of the UK Agency for International Development and the general requirements of the rural revitalization strategy on industry, ecology, rural ethos, governance and life, this paper selects the material basis, living environment and Social Adaptability which are more close to China’s national conditions and can more accurately measure the resettlers’ livelihood. These three factors have established a Comprehensive Evaluation Index System for the sustainable livelihood of the reservoir resettlers. A mathematical model based on complex fuzzy matter-element and analytic hierarchy process (AHP) is established to assess the sustainable livelihood of reservoir resettlers. Furthermore, it conducts an empirical study on the resettlement of the Danjiangkou Henan Reservoir area of the South-to-North Water Diversion Project, which takes the whole of immigration in Henan Province as the research object.Results: The results show that the current survey value of the overall livelihood of the resettlers in the Danjiangkou Henan Reservoir Area of the South-to-North Water Diversion Project is 0.0085 lower than the maintaining livelihood target and 0.1725 lower than the sustainable livelihood target. Such a result indicates that the livelihood of Henan resettlers in the Danjiangkou Henan Reservoir Area of the South-to-North Water Diversion Project has reached a sustainable level overall, but its gap with the sustainable livelihood goal remains obvious, which is primarily demonstrated by economic foundation and social adaptability.Discussion: Therefore, immigration management agencies should make efforts to adjust the industrial structure, increase the income of resettlers, help resettlers integrate into the local society sooner, and promote the sustainable development of resettlers’ livelihoods.

Integrating GRACE/GRACE Follow-On and Wells Data to Detect Groundwater Storage Recovery at a Small-Scale in Beijing Using Deep Learning

Groundwater depletion is adversely affecting Beijing’s ecology and environment. However, the effective execution of the South-to-North Water Diversion Project’s middle route (SNDWP-MR) is anticipated to mitigate Beijing’s groundwater depletion. Here, we propose a robust hybrid statistical downscaling method aimed at enhancing the capability of the Gravity Recovery and Climate Experiment (GRACE) to detect the small-scale groundwater storage anomaly (GWSA) in Beijing. We used three deep learning (DL) methods to reconstruct the 0.5° × 0.5° terrestrial water storage anomaly (TWSA) between 2004 and 2021. Moreover, multiple processing strategies were used to downscale the GWSA to 0.25° from 2004 to 2021 by integrating wells and GRACE/GRACE follow-on data from the optimal DL model. Additionally, we analyzed the spatiotemporal evolution trends of GW in Beijing before and after the implementation of the SNDWP-MR. The results show that the long short-term memory model delivers optimal performance in the TWSA reconstruction of Beijing, with the correlation coefficient (CC), Nash–Sutcliffe coefficient (NSE), and root mean square error (RMSE) being 0.98, 0.96, and 10.19 mm, respectively. The GWSA before and after downscaling is basically consistent with wells data, but the CC and RMSE of downscaling the GWSA from 2004 to 2021 are improving by 34% and 31%, respectively. Before the SNDWP-MR (2004–2014), the trend of GWSA in Beijing was −17.68 ± 4.46 mm/y, with a human contribution of 69.30%. After SNDWP-MR (2015–2021), GWSA gradually increased by 10.00 mm per year, with the SNDWP-MR accounting for 18.30%. This study delivers a technical innovation reference for dynamically monitoring a small-scale GWSA from GRACE/GRACE-FO data.

Precise ecological restoration under water diversions-groundwater-ecosystem interactions in drylands

Ecological Water Diversion Projects (EWDPs) have been employed worldwide to restore degraded ecosystems in drylands, but precise restoration locations and planting species under EWDP remain unknown, even if it has changed ecohydrological dynamics. Therefore, this study proposed a water diversions-groundwater-vegetation coupling framework based on Machine Learning for deciding where to restore in drylands. The Shapley Additive Explanation method was used to interpret the framework and disentangle the role of the local environment in defining vegetation patterns from a data-driven perspective. This approach was tested in a mega EWDP in the lower Tarim River Basin (TRB), Northwest China, in present and future restoration locations, and planting species were quantitatively estimated. The results showed that the terrain and groundwater table critically impact the vegetation communities in arid regions. Currently, 4.3% of the existing land should be trees and grass, while they account for 0.1% of the lower TRB in total. Within the next decade, the potential reforestation of areas with steadily growing natural vegetation would decrease by 5.3% and 12.6% if the yearly watering volume of EWPD decreased by 28.6% under climate change scenarios SSP245 and SSP585, respectively. Our results confirm the substantial variability in restoration areas under varying diversion volumes and underscore the importance of incorporating EWDP into future restoration management. The proposed approach can form a scientific basis for dryland precision restoration to facilitate water conservation and maximize ecological benefit.

Comprehensive Benefit Assessment of the Middle Route of South-to-North Water Diversion Project Based on Markowitz Theory

Comprehensive Benefit Assessment of the Middle Route of South-to-North Water Diversion Project Based on Markowitz Theory

Quantifying recharge sources to groundwater to an oasis area: Implications for strengthening water resource management under changing environmental conditions

AbstractIn order to implement sustainable management of water resources in the Desert Oasis, it is necessary to quantify the changes in the groundwater recharge process. Using the Cl−, stable hydrogen and oxygen isotope datasets extracted from 113 groundwater samples in the years of 2000 and 2020, and combining these with the MixSIAR model, changes in the groundwater recharge process and recharge source contributions in the Minqin Oasis (MO) in northwestern China area before and after ecological treatment were quantitatively analysed. Overall, confined groundwater was the greatest contributor to the recharge of shallow groundwater in the MO area in 2000. However, after 10 years of ecological rehabilitation, surface water has become the most important recharge source of shallow groundwater, with its contribution increasing by 10.6% between 2000 and 2020 ~ 2021. River water diversion projects have reversed falling groundwater levels in the MO area. Of these projects, that in the MO has seen groundwater levels rise at a rate of 0.09 m·year−1 from 2008 to 2019. This coincides with the increase in the contribution of surface water to groundwater recharge in 2020. In addition, insignificant changes were observed in the contributions made by lateral groundwater flow to groundwater recharge in the MO area in the years of 2000 and 2020 ~ 2021, indicating that groundwater in the upper and middle reaches of the MO area have contributed very little to the restoration of groundwater levels in the area's lower reaches. All these factors would appear to indicate that regional ecological management has had a lasting impact, and that the exploitation of groundwater in this desert oasis area in an inland river basin should be based upon rational planning and integrated, comprehensive management strategies.

Prediction of phytoplankton biomass and identification of key influencing factors using interpretable machine learning models

The water quality of the Middle Route of the South-to-North Water Diversion Project (MRP) of China is related to the health and safety of about 8500w people. In recent years, multiple occurrences of abnormal algal proliferation in water conveyance channels have posed potential risks to the water quality of diverted water. To clarify the growth situation of phytoplankton and evaluate the response relationships between water environmental parameters and phytoplankton in the MRP, in this study, a long-term monitoring dataset was collected from seven monitoring sites from May 2015 to December 2020 to statistically analyse the spatiotemporal characteristics of planktonic algal cell density (ACD). Based on this, four machine learning models, including multiple linear regression (MLR), support vector regression (SVR), random forest (RF), and extreme gradient boosting (XBGoost), were constructed to predict the ACD, and the SHapely Additive exPlanations (SHAP) method was used to interpret the best prediction model for identifying the response relationship between water environmental parameters and ACD. The results showed that (1) the seven monitoring sites could be divided into two significant groups (i.e., Group I and Group II) by hierarchical clustering analysis (HCA), among which the ACD of Group II was higher than that of Group I. (2) the performance of four prediction models using different evaluation metrics indicated that the RF model surpassed in prediction accuracy compared with the other three models in predicting ACD variations in Group I and Group II. (3) SHAP analysis revealed that the key factors affecting ACD variations in Group I were water temperature (WT), water depth (WD), permanganate index (PI), flow rate (Q) and dissolved oxygen (DO), and the ACD were inhibited when WT was below 23 °C, WD exceeded 6.5 m, and Q was between 100 and 250 m3/s. Additionally, WT, PI, and DO were the most important predictors of ACD in Group II, and ACD were inhibited when WT was below 24 °C, PI was lower than 2.4 mg/L and DO was higher than 9 mg/L. This research provides a theoretical basis and reference for water quality management and algal ecological control of water transfer projects with high spatial heterogeneity.

Research on water quality improvement of plain irrigation area based on multi-scenario simulation.

Water diversion projects have proven to be effective interventions to improve water quality in irrigation ditches. This study focused on quantifying the water quality improvement by utilizing a hydrodynamic water quality model in Funing County, Yancheng City. The model performed a spatial analysis of pollution concentrations across the study area. Various optimization scenarios were designed based on the diversion project and hydrological structure connectivity. The model was used to simulate changes in nutrient concentrations under different scenarios. The findings of this study were as follows: (1) Rural areas had lower nutrient concentrations and superior hydrological connectivity than urban areas. (2) The effect of water quality improvement correlated positively with increased flow rates introduced by the diversion project. Specifically, when the flow rate increased by 50%, the average reductions were 20% for NH4+, 5.2% for TN, and 5.1% for TP. Furthermore, introduced clean water led to more pronounced improvements in the overall regional water quality. (3) Although increasing the number of ditches improved water pollution concentration, the impact was not significant. (4) Model simulation results showed that 18 to 45% water diversion intensity effectively improved water quality, and the optimal water diversion intensity was 27 to 30%. The optimal water diversion intensities offered valuable insights for managing this region. The study's methods contributed to the promotion of sustainable development in regional water resources and the integrated management of the water environment.

Alteration Mechanism of Variscan Granite in a Project Area at the Northern Foot of the Tianshan Mountains, China

Long-term erosion of granite—a type of hard rock—by hydrothermal fluids and tectonic movement can lead to a fragmentation of the internal structure of the original rock, transfer/replacement of mineral elements, and alteration of the rock’s basic properties. Such changes can be problematic for the construction of water conservancy, hydropower, and road projects. This study adopted the altered Variscan granite in a water diversion project area at the northern foot of the Tianshan Mountains (China) as the research object, and explored the alteration mechanism using thin section identification, X-ray diffraction, major element analysis, and electron probe and oxygen isotope tests. Results showed that the lithology of the granite in the study area is mainly biotite granodiorite and biotite monzonitic granite. Reductions in both the K+ content in plagioclase and the K+ and Ti4+ contents in chlorite indicate that the alteration types within the study area are mainly clayization of feldspar minerals and chloritization of biotite. Biotite granodiorite and biotite monzonitic granite both have low δ18O values. The δ18O value of biotite granodiorite decreases with increase in the Loss on Ignition. The low-δ18O-value granodiorite due to an alteration by hydrothermal fluids transformed from glacier meltwater, groundwater, atmospheric precipitation, and magmatic water; whereas the monzonitic granite might be formed by the reinvasion of low-δ18O-value granodiorite formed in the early stage, which is remelted, assimilated, and rebalanced. The research findings provide a reference for similar research on altered granite at the northern foot of the Tianshan Mountains, and also lay a foundation for subsequent research on its physical/mechanical properties and engineering characteristics.

Spatial distribution, ecological risk and origin of soil heavy metals in Laoguanhe watershed of China's South-to-North Water Diversion Middle Route Project

The central section of China's South-to-North Water Diversion Project has been designated as a national water conservation area, and the soil ecological security in its associated watersheds is of great importance. A total of 204 soil samples (0–20 cm depth) were obtained from the Laoguanhe River Basin. The concentrations of seven elements (Cd, Cr, Cu, Ni, Zn, Pb and Hg) were determined using inductively coupled plasma mass spectrometry and atomic fluorescence spectrometry following a near-total acid dissolution. Data analyses (including potential ecological risk, principal component analysis, geostatistical analysis and the positive matrix factorization model) were applied to evaluate the contamination of soil heavy metals and to identify their sources. The research results demonstrated that the mean contents of these seven elements exceeded background values for Henan Province, China, indicating human disturbance. Ecological risk evaluation revealed that Cd was the most frequently detected and the heavy metal causing the most pollution. Principal component analysis indicated that Cr, Ni and Cu stem from natural sources, while Zn and Cd are predominantly influenced by agricultural activities. Additionally, industrial activities and atmospheric deposition were responsible for the excess presence of Pb and Hg. The study suggests taking measures to control Cd sources in agricultural areas, reducing input of heavy metals into the river and providing scientific support for managing water quality.

Application of passive sampling device for exploring the occurrence, distribution, and risk of pharmaceuticals and pesticides in surface water

Pharmaceuticals and pesticides are compounds of high concern in surface waters around the world. However, few studies have used passive sampling methods to screen and detect these compounds in natural waters. In this study, a self-developed passive sampler was employed to measure pharmaceuticals and pesticides in the rivers of Nanjing, China. A total of 41 pharmaceuticals and 11 pesticides were detected, among which antibiotic and insecticide were the predominant classes, respectively. Valproic acid, caffeine and triclosan from the pharmaceuticals, and isoprocarb and imidacloprid from the pesticides were found frequently with high concentrations. At most sampling sites, the concentration ratios of caffeine versus carbamazepine exceeded 10, and even above 50, indicating relatively poor efficiency of wastewater treatment, or possibly the direct discharge of raw sewage, or other unknown source of pollution. It was found that the concentrations and ecological risks in the northern area of Yangtze River were higher than those in the southern area of Yangtze River, implying that economic development and population density were not the main contributors to the discovered pollution. The total concentration of pharmaceuticals and pesticides in Qinhuai River increased gradually with the direction of water flow, demonstrating the success of water diversion project in flushing and scouring pollutants.

The Application of the Underwater Repair of Concrete Lining Slabs in the South-to-North Water Diversion Project

The cracking of concrete linings in the channel of the Yuzhou section of the South-to-North Water Diversion Project in Henan Province poses a threat to the structural safety of the project and the water quality environment. To solve this problem, the mixing ratio of non-dispersible underwater concrete (NUC) was optimized, the bond strength of new and old concrete was measured, and an underwater repair methodology of the linings was proposed using NUC. The results showed that adding 2.5% of UWB-Ⅱ-type anti-dispersant resulted in NUC with a 28-day underwater compressive strength of 25.1 MPa and a strength ratio of 0.9 between land and water. The effects of water–cement ratio, anti-dispersant dosage, and fly ash dosage on the performance of the NUC were revealed through experiments, and the mix ratio of NUC was optimized. Bond strength measurement at the interface between the NUC and old concrete was tested using the straight shear test. The test results showed that the bond strength between non-dispersible concrete and ordinary concrete was higher than that between ordinary concrete of the same strength grade. Through an analysis of the ionic composition of the water, it was verified that the NUC did not affect the water quality. Therefore, NUC can provide a reference for the underwater repair of the lining panel of the South-to-North Water Diversion Project.

Total Dissolved Solids Risk Assessment and Optimisation Scheme of Managed Aquifer Recharge Projects in a Karst Area of Northern China

Jinan, China, is famous for its springs. However, societal and economic development over the past decades has detrimentally altered the natural water cycle in the spring area. Managed aquifer recharge (MAR) is an effective measure to ensure the normal gushing of springs. Balancing water resource utilisation, ecological effects, and water quality risks is not always easy to implement. This study focused on the potential effects of MAR projects that divert water from multiple local surface water sites, e.g., the Yellow River and South-to-North Water Diversion (SNWD) Project. A numerical simulation model for the entire spring area was built using MODFLOW and MT3DMS. The SNWD Project diverts water with relatively high total dissolved solids (TDS) to the Yufu River, which consequently recharges groundwater and poses a potential risk to the downstream karst water in the Jinan Spring area. Different simulation scenarios were set, and the results showed that the 90% recovery ratio scheme yields the highest TDS reduction efficiency as well as the largest karst water extraction volume. In addition, the water table remains stable as a whole. The benefits of the designed scheme are multifold, including improving water quality up to Standard III groundwater quality and meeting the water needs of the economy. The study provides a novel method of addressing the groundwater quality risks posed by artificial recharge.