Groundwater Resources Management Modelling: A Review

Globally, groundwater is the largest distributed storage of freshwater that plays an important role in an ecosystem’s sustainability in addition to aiding human adaptation to both climatic change and variability. However, groundwater resources are dynamic and often changes as a result of land usage, abstraction as well as variation in climate. Thus, efficient management of groundwater resources to prevent overexploitation, scarcity, and minimising the effects of drought has become a major challenge for researchers as well as water managers. Furthermore, a number of research challenges such as the lack of computational efficiency and scalability due to uncertainties from input parameters to the groundwater resource model have been revealed in the management of groundwater resources. To solve these challenges, many conventional solutions such as numerical techniques have been proffered for groundwater modelling. Also, the use of data-driven techniques such as machine learning is gaining more attraction to solve these aforementioned challenges. Thus, this has made efficient data gathering essential to maintain da-ta-driven groundwater resources management models from the observation site. The global evolution of the Internet of Things (IoTs), has increased the nature of data gathering for the management of groundwater resources. In addition, efficient data-driven groundwater resource management relies hugely on information relating to changes in groundwater resources as well as their availability. Although the IoTs enabled automated data processing systems are in existence by transmitting the generated data from IoT enabled devices into the cloud through the Internet. However, traditional IoT Internet is not scalable and efficient enough to process the generated vast IoT data At the moment, some pieces of the literature revealed the groundwater managers lack an efficient, scalable and real-time groundwater management system to gather the required data. Also, the literature revealed that the existing methods of collecting data lack efficiency to meet computational model requirements and meet management objectives. Thus, it is necessary to have an efficient and scalable IoT system to extract valuable information in real-time for groundwater resource management. Unlike previous surveys which solely focussed on particular groundwater issues related to simulation and optimisation management methods, nonetheless, this paper seeks to highlight the current groundwater management models as well as the IoT contributions

Hydrogeochemical Characteristics and Formation Processes of Ordovician Limestone Groundwater in Zhuozishan Coalfield, Northwest China

Groundwater is essential for water supplies in arid and semi-arid region. Analyzing the characteristics and formation mechanisms of groundwater in mining area is crucial for coal mine water prevention and rational groundwater resources management. This study reached the hydrogeochemical characteristics and evolutions of Ordovician groundwater in the zhuozishan coal mine, northwest China.34 groundwater samples were collected for hydrogeochemical analyses and piper trilinear diagram, gibbs diagram, ion ratio diagram were used to research groundwater formation processes. The results indicate that the concentration of Na++ K+, HCO3−, Cl−, SO42−, TDS, and pH increase from the recharge area to the discharge area, however, that of Ca2+ and Mg2+ decreases.And each indicator varied greatly in the north and south of the coalfield. Hydrogeochemical types of the runoff from Zhuozishan Mountain to Gongdeer Mountain and then to the south-north directional change obviously. And the groundwater process is controlled by rock weathering action and cation exchange. Whereas the hydrochemical type of the runoff from Zhuozishan Mountain to the south is always SO4▪Cl-Ca▪Na type, and groundwater process is controlled from rock weathering action to evaporation concentration and reverse cation exchange. When it comes to ion source, Ca2+ and Mg2+ mainly origin from the silicate dissolution, while Na+ and K+ are mainly derived from cation exchange and barely from the halite dissolution. In summary,in the northern part of the coalfield, due to geological structure, a retention area is formed with groundwater, and the runoff process is disordered with a complicated formation process. The middle part is not blocked by the geological structure, the runoff direction do not change, so the formation of groundwater is simple. And in the southern part, due to the deepening stratum and fault blocking, a retention zone is formed, making groundwater formation process more complicated. This study will contribute to groundwater resources management and mine water inrush control in this coalfield and at other mines.

Hydrogeochemical and Hydrodynamic Assessment of Tirnavos Basin, Central Greece

A combined hydrogeochemical and hydrodynamic characterization for the assessment of key aspects related to groundwater resources management was performed in a highly productive agricultural basin of the Thessaly region in central Greece. A complementary suite of tools and methods—including graphical processing, hydrogeochemical modeling, multivariate statistics and environmental isotopes—have been applied to a comprehensive dataset of physicochemical analyses and water level measurements. Results revealed that the initial hydrogeochemistry of groundwater was progressively impacted by secondary phenomena (e.g., ion exchange and redox reactions) which were clearly delineated into distinct zones according to data processing. The progressive evolution of groundwater was further verified by the variation of the saturation indices of critical minerals. In addition, the combined use of water level measurements delineated the major pathways of groundwater flow. Interestingly, the additional joint assessment of environmental isotopes revealed a new pathway from E–NE (which had never before been validated), thus highlighting the importance of the joint tools/methods application in complex scientific tasks. The application of multivariate statistics identified the dominant processes that control hydrogeochemistry and fit well with identified hydrodynamic mechanisms. These included (as dominant factor) the salinization impact due to the combined use of irrigation water return and evaporitic mineral leaching, as well as the impact of the geogenic calcareous substrate (mainly karstic calcareous formations and dolostones). Secondary factors, acting as processes (e.g., redox and ion exchange), were identified and found to be in line with initial assessment, thus validating the overall characterization. Finally, the outcomes may prove to be valuable in the progression toward sustainable groundwater resources management. The results have provided spatial and temporal information for significant parameters, sources, and processes—which, as a methodological approach, could be adopted in similar cases of other catchments.

Joint actions for more efficient management of common groundwater resources in Estonia and Latvia

<p>European water policy requires to carry out nine tests for characterisation of groundwater bodies status, including the development of joint transboundary groundwater management principles. </p><p>Gauja/Koiva and Salaca/Salatsi Rivers have a joint, Estonian/Latvian transboundary water cycle, including the groundwater recharge and discharge cycling. Despite the fact that groundwater is the only drinking water source in Gauja/Koiva and Salaca/Salatsi River basins and ensures the existence of many groundwater dependent ecosystems, the overall awareness of integrated cross-border management practice is still poorly understood and poorly linked in implementation of concrete groundwater protection actions. </p><p>Taking into account the above-mentioned aspects, Latvian and Estonian groundwater and groundwater dependent ecosystems specialists from research, nature protection and groundwater resources management institutions have joined forces in the project funded by the Interreg Estonia-Latvia program: "Joint actions for more efficient management of common groundwater resources in Estonia and Latvia "(WaterAct).</p><p>The ongoing Est-Lat project “WaterAct” (2020–2022) of joint transboundary groundwater management project organised into the three activity blocks: (1) The capacity building of the joint groundwater transboundary management through exchange of knowledge and best management practices between project partners and key experts in other European Union countries; (2) Assessment of groundwater resources in transboundary River basins to improve groundwater management in accordance with valid international directives; (3) Dissemination and outreach activities to increase the overall awareness of ecosystems friendly groundwater management and protection of key actors working with groundwater assessments and locals. </p><p>Firstly, the joint cross-boundary principles of identification and status assessment of shared groundwater bodies will be developed. Adaptation of existing knowledge, cross-boundary harmonization and development of needed methodologies will be used. </p><p>Secondly, the joint cross-boundary assessment principles will be implemented into groundwater resources management. The status assessment of shared groundwater bodies will be carried out in close cooperation between project partners to create materials necessary for the development of last River Basin Management Plans (2022-2027), required by the Water Framework Directive and Groundwater Directive.</p><p>Thirdly, the dissemination of project results will be carried out (1) by compilation of Guidelines of Groundwater Dependent Ecosystems for different levels and fields of decision making and experts, (2) by compilation of Spring Water Monitoring Guide for Volunteers and starting volunteer monitoring. For volunteer monitoring, a special web-based map application will be developed (allikad.info). </p><p> </p><p>The project of “Joint actions for more efficient management of common groundwater resources” (WaterAct, Est-Lat155) funded by ERDF Interreg Estonia-Latvia cooperation programme.</p>