New organic groundwater pollutants in the national groundwater monitoring network of Poland

Chalk and limestone aquifers contribute one-third of the drinking water supply in Denmark, and one-sixth of that national groundwater resource is assessed as having a ‘Poor’ status in terms of the quantitative Water Framework Directive due to intensive abstraction. This paper describes the national groundwater level monitoring network with regard to the following three applications: (1) when used for the annual surveying and reporting of groundwater resources and impacts from climate and groundwater abstraction; (2) as part of real-time monitoring and modelling for daily and seasonal forecasting; and (3) for tracking long-term climate change impacts on groundwater levels. Groundwater level monitoring provides a particularly important indicator of abstraction pressure and sustainable balance compared with recharge. Many larger chalk and limestone groundwater bodies in Denmark are only monitored by local water companies and not represented in the national groundwater level network. This raises the concern that current national groundwater level monitoring does not fully support integrated modelling and assessment purposes for chalk and limestone groundwater bodies. This also implies that, for tracking long-term climate change and anthropogenic impacts on groundwater levels, the national groundwater monitoring network especially lacks long-term records with complete 30-year time-series for many intensively exploited large chalk and limestone aquifers.

Physicochemical patterns observed in a groundwater well with CO2 stratification: Learnings from an automated monitoring from South Korean national groundwater monitoring network

ABSTRACTWe explore a hypothetical zero-latency earthquake early warning (EEW) system in Greece, aiming to provide alerts before warning thresholds of the intensity of ground motion are exceeded. Within the seismotectonic context of Greece, both shallow- and intermediate-depth earthquakes (along the Hellenic subduction zone) are plausible and, thus, examined. Using regionally applicable attenuation relations, we combine and adjust the methodologies of Minson et al. (2018) and Hoshiba (2020) to examine what are the minimum magnitudes required to invoke the warning thresholds at the user site. With simple modeling, we examine how fast an alert can be issued and what is the available warning time when taking into account delays due to finite-fault rupture propagation, alongside other delays. These computations are merged with delays introduced due to the present-day configuration of the Greek national monitoring network (varying spatial density of permanent monitoring stations). This approach serves as a tool to assess the feasibility of an EEW system at specific sites and to redesign the national permanent monitoring network to serve such a system more effectively (we provide results for four sites.). Warning times for on-land crustal earthquakes are found to be shorter, whereas for intermediate-depth earthquakes in Greece an EEW system is feasible (provides warning times of several tens of seconds at large cities, e.g., on Crete Island) even with the current configuration of the national monitoring network, which is quite sparse in the southern part of the country. The current network configuration also provides sufficient early warning (e.g., of the order of 10 s for a warning threshold of 0.05g) at the center of Athens from earthquakes of the eastern Gulf of Corinth—a zone posing elevated hazard in the broader area of the Greek capital. Several additional assumptions and factors affecting the operability of an EEW system in Greece (i.e., source process complexity and uncertainty in attenuation laws) are also discussed.

<p>Georgia is among the countries which have fresh groundwater distinguished for significant resources and drinking qualities of naturally high quality. Hydrogeological exploration and monitoring works for the purpose of identification, study and protection of fresh groundwater were not conducted in the period of 1990–2013. Considering the long-term termination of centralized researches and the intensively increasing anthropogenic pressures on the environment and on water in particular, the assessment and protection of groundwater resources becomes a very pressing issue. For this purpose, in 2013, on initiative of the Geology Department of LEPL National Environmental Agency of Georgia and the Czech Development Agency, restoration of the hydrogeological monitoring network and research of fresh groundwater using modern methodology began. The modern equipment was gradually installed on the water objects to obtain information about quantitative and qualitative characteristics in "online" mode and taking water samples for chemical and bacterial analysis twice a year. Currently, 56 water points (mainly wells) are being monitored. The database on quantitative and qualitative characteristics of fresh groundwater of Georgia is being expanding based on information received online from water points, fieldwork results, laboratory analyzes (chemical and bacteriological), and on the processing, analyzing and generalizing of the collected actual materials. As the issue concerns fresh groundwater (which is used by at least 90% of the population), it’s necessary to expand the state monitoring network. According to the EU Water Framework Directive, based on the basin management principles of water resources, conduct of researches is granted particular significance in the trans-boundary zone.</p><p>The „European Union Water Initiative Plus for Eastern Partnership (EaP) Countries (EUWI+)″, which is the biggest commitment of the EU to the water sector in the EaP countries, helps Armenia, Azerbaijan, Belarus, Georgia, Moldova and Ukraine to bring their legislation closer to EU policy in the field of water management, as identified by the EU Water Framework Directive. The EUWI+ project addresses existing challenges in both development and implementation of efficient management of water resources.. Monitoring data are an important basis for water management, for risk, status and trend assessment and for the design and implementation of an effective and cost-efficient program of measures .</p><p>Within the EUWI+ project, the following key activities were undertaken in Georgia: „Delineation and characterization of groundwater bodies and the design of a groundwater monitoring network in the Alazani-Iori and Khrami-Debed River Basin Districts in Georgia“, „Performed hydrogeological preliminary field works in the Alazani-Iori and Khrami-Debed River Basin“. Currently „Geophysical, isotope, hydrochemical, bacteriological and hydrodynamic assessment of twelve selected wells to be included in the national groundwater monitoring network in the Alazani-Iori River Basin District in Georgia“ is in progress. The results of this study are a basis for the improvement of the groundwater monitoring network and the development of River Basin Management Plans. As a part of the EUWI+ project, several new monitoring stations are planned.</p><p>The results are important in the process of implementation of integrated management of water resources, which should finally ensure sustainable management of water resources and reliable health protection of the population.</p>

In the Nile Valley and Delta the protection of groundwater resources is high priority environmental concern. Many groundwater quality problems are already dispersed and may be widespread and frequent in occurrence. Examples include problems associated with the extensive application of chemical fertilizers in agricultural specially in the new reclaimed areas, leaks in sewers, septic tanks, the aggregate effects of many different points source pollution in urban areas and natural, geologically related water quality problems. A national groundwater quality monitoring has been designed and implemented based on the stepwise procedure. The national groundwater quality monitoring network is used to quantify the quality changes in long run, either caused by pollution activities or by salt water intrusion and to describe the overall current groundwater quality status on a national scale of the main aquifers. The monitoring tools and methodologies developed in this research can be used to assure protection of public health and determine the sustainability of groundwater in various purposes. This national monitoring network plays important roles for decision makers in developing the groundwater resources management plans in different aquifers systems in Egypt.

Abstract. Various studies have been carried out since 2005 under the leadership of Ministry of Environment and Urbanism of Turkey, in order to observe the quality of air in Turkey, to develop new policies and to develop a sustainable air quality management strategy. For this reason, a national air quality monitoring network has been developed providing air quality indices. By this network, the quality of the air has been continuously monitored and an important information system has been constructed in order to take precautions for preventing a dangerous situation. The biggest handicap in the network is the data access problem for instant and time series data acquisition and processing because of its proprietary structure. Currently, there is no service offered by the current air quality monitoring system for exchanging information with third party applications. Within the context of this work, a web service has been developed to enable location based querying of the current/past air quality data in Turkey. This web service is equipped with up-todate and widely preferred technologies. In other words, an architecture is chosen in which applications can easily integrate. In the second phase of the study, a web-based application was developed to test the developed web service and this testing application can perform location based acquisition of air-quality data. This makes it possible to easily carry out operations such as screening and examination of the area in the given time-frame which cannot be done with the national monitoring network.

In the Netherlands, there is no national groundwater monitoring network. The national government has delegated groundwater quantity management to the regional authorities, which perform groundwater head monitoring for this purpose. The regional authorities upload their groundwater head measurements to a national repository that is maintained by TNO Geological Survey of the Netherlands (TNO-GSN).As part of the Geological Survey task,  TNO-GSN makes available information based on these groundwater head measurements through an online Groundwater head viewer (https://www.grondwatertools.nl/gwsinbeeld). Currently, we are working on an extension of this viewer to show the status of the heads for the entire country. The aim is to give a data driven assessment which is independent of physics based distributed three dimensional groundwater modelling. The main reason is that the use of such modelling depends on successful calibration of a national groundwater model and on inclusion of all relevant processes and changes in boundary conditions (land use, pumping, water management, . . .). A second reason is that an independent assessments helps to improve the existing national model (https://nhi.nu) and better understand the changes in the Dutch groundwater system. For the assessment a limited number of monitoring wells are selected, so that the status can be shown qualitatively by colouring the dots. The main challenge is make a representative selection for:Yearly change of groundwater volume. Drought or wetness. Regional differences. The 3 dimensional character of the groundwater system: not only phreatic but also deeper aquifers. Assessment of large scale trends caused by e.g. climate change, urbanisation. Effectiveness of large scale governance measures (‘water en bodem sturend’). Monitoring wells in the national database are selected based on the following criteria:Being used currently; The longer the measurement timeseries the better; Preferably multilevel; Spatial spread and variation in land use; Covering national variation in precipitation and reference evaporation; Covering range of response times of transfer-noise models with precipitation and reference evaporation as explaining variables; Preferably equipped with telemetry and transmitting data to the national database daily. The current groundwater head for each piezometer can be characterized in various ways, with and without seasonal correction, such as the percentile of all measurements or all measurements in the same month, or a percentile in the regime curve generated with a 30-year simulation of a timeseries model with precipitation and evaporation.The resulting selection will be a useful extension of the trends, vertical head differences, dynamics already available on the Groundwater head viewer for national operational water management, groundwater governance and outreach.

A variety of policies have been suggested and implemented for air quality control in Korea. However, high ambient concentrations of PM10 and PM2.5 exceeding regulation levels have been frequently reported. In this study, the air quality in Gyeongsangbuk-do including 10 cities (si) and 12 counties (gun) was analyzed using data from the national air pollution monitoring network and from the clean air policy support system (CAPSS) from 2017 to 2021. The national air pollution monitoring network data showed that the concentrations of CO, NO2, SO2, PM10, and PM2.5 decreased gradually and the concentration of O3 maintained constantly during 5 years. The data from the CAPSS indicated that the main sources of CO, NOx, SOx, VOCs, and NH3, were the biomass combustion, road/non-road mobile sources, industrial activities, organic solvents usage, and agriculture, respectively. In addition, the main sources of total suspended particulate (TSP), PM10, and PM2.5 were fugitive dust and biomass combustion. It was found that no significant linear relationship between the air quality concentrations data and CAPSS data due to the different characteristics of the two data groups. Moreover, machine learning models were established using the national air pollution monitoring network data, CAPSS data, meteorological data, and socio-economic indices to predict the concentrations of PM10 and PM2.5. It was revealed that the concentrations of PM10 and PM2.5 were significantly affected by the emissions of CO and PM2.5 (CAPSS) and electricity, gas, steam, and air conditioning supply, respectively.

Groundwater is a vital drinking water resource and its protection from microbiological contamination is paramount to safeguard public health. The Republic of Ireland (RoI) is characterised by the highest incidence of verocytotoxigenic Escherichia coli (VTEC) enteritis in the European Union (EU), linked to high reliance on unregulated groundwater sources (~16% of the population). Yet, the spatio-temporal factors influencing the frequency and magnitude of microbial contamination remain largely unknown, with past studies typically constrained to spatio-temporally ‘limited’ sampling campaigns. Accordingly, the current investigation sought to analyse an extensive spatially distributed time-series (2011−2020) of groundwater monitoring data in the RoI. The dataset, compiled by the Environmental Protection Agency (EPA), showed ‘high’ contamination rates, with 66.7% (88/132) of supplies testing positive for E. coli, and 29.5% (39/132) exceeding concentrations of 10MPN/100 ml (i.e. gross contamination) at least once during the 10-year monitoring period. Seasonal decomposition analyses indicate that E. coli detection rates peak during late autumn/early winter, coinciding with increases in annual rainfall, while gross contamination peaks in spring (May) and late-summer (August), likely reflecting seasonal shifts in agricultural practices. Mixed effects logistic regression modelling indicates that monitoring sources located in karst limestone are statistically associated with E. coli presence (OR = 2.76, p = 0.03) and gross contamination (OR = 2.54, p = 0.037) when compared to poorly productive aquifers (i.e., transmissivity below 10m2/d). Moreover, 5-day and 30-day antecedent rainfall increased the likelihood of E. coli contamination (OR = 1.027, p < 0.001 and OR = 1.005, p = 0.016, respectively), with the former also being associated with gross contamination (OR = 1.042, p < 0.001). As such, it is inferred that preferential flow and direct ingress of surface runoff are the most likely ingress mechanisms associated with E. coli groundwater supply contamination. The results presented are expected to inform policy change around groundwater source protection and provide insight for the development of groundwater monitoring programmes in geologically heterogeneous regions.

The drastic expansion of cities and the rapid economic growth in Korea have caused dramatic increases to demand from groundwater supplies for drinking, domestic, agricultural and industrial water usage. The Ministry of Construction and Transportation and the Korea Water Resources Corporation have constructed and operated the National Groundwater Monitoring Network (NGMN) throughout the country since 1995. The NGMN, an official project establishing a total of 320 groundwater monitoring stations, was completed in 2005. Each national groundwater monitoring station serves as a baseline and primary station to monitor long‐term general trends in water‐level fluctuations and in groundwater quality. The present NGMN and its monitoring capabilities were evaluated to enhance the efficiency of groundwater monitoring and to meet the new societal conditions. Based on reviews and evaluations, some suggestions and recommendations are made with regard to improvements of the national network, including the installation of rainfall gauges in groundwater monitoring stations, gathering groundwater data every hour instead of every 6 h as at present, involving major cations and anions in the regular and periodic chemical analyses, regular periodic analyses of collected groundwater data, and construction of 199 additional groundwater monitoring stations to supplement the existing groundwater monitoring network. Copyright © 2006 John Wiley &amp; Sons, Ltd.

A review of national monitoring networks in North America

In 2021, China adopted comprehensive “Groundwater Management Regulations” to address critical groundwater issues, building upon the foundation of a national groundwater monitoring network established by 2020. This commentary reviews the development of China's National Groundwater Monitoring Network, examines its current monitoring capacity, and highlights ongoing groundwater issues and related ecological and environmental challenges. The network now comprises over 20,000 monitoring wells across 10 major river basins in China. Despite this progress, three key challenges persist in advancing groundwater knowledge: (a) insufficient data from the Tibetan Plateau, a crucial headwater region for many of Asia's major rivers; (b) limited understanding of how groundwater systems affect ecohydrological processes and ecosystem services; and (c) the identification and mitigation of environmental geological hazards driven by groundwater changes. We advocate for the integration of the groundwater observational data with physics‐based groundwater models, artificial intelligence, and deep learning techniques to deepen our understanding of these complex, largely hidden groundwater systems, providing critical insights for both scientific research and regulatory decision‐making.

Currently observed climate changes have contributed to an increase in the frequency and intensity of extreme weather events across the globe. On one hand, many regions experience frequent and prolonged droughts; on the other, numerous areas face intense heavy rainfall, which often leads to flooding. A particularly alarming challenge for water resources arises when these phenomena occur alternately in the same region. Dry soil, especially when heavily cracked, loses its ability to absorb water efficiently. As a result, intense rainfall tends to generate surface runoff rather than replenishing the soil&amp;#8217;s water reserves. This runoff often leads to soil erosion, decreased water retention, and an increased risk of flooding. Such conditions exacerbate water scarcity for ecosystems and human populations, posing significant risks to agriculture and other sectors reliant on stable water supplies. The long-term disruptions to hydrological cycles driven by these alternating extremes represent some of the most critical consequences of climate change.One example of a region that has experienced both severe droughts and floods in recent years is Poland. In 2024, for instance, the country faced agricultural drought conditions for much of the spring and summer, while intense rainfall in September led to sudden river surges and flooding.This study focuses on analysing changes in water resources in Poland, which are clearly influenced by climate change. For the study area, we analyse terrestrial water storage (TWS) based on observations from the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions, as well as model data. Additionally, we examine changes in groundwater storage (GWS), which play a crucial role in providing drinking water to the region. To achieve this, we use data from measurement points within the national groundwater monitoring network, in addition to satellite data. We then identify extreme changes in TWS and GWS and look for links between these phenomena and the patterns of precipitation and evapotranspiration recorded in the region. For this purpose, we use well-established climate indices such as Standardized Precipitation Index (SPI), Standardised Precipitation-Evapotranspiration Index (SPEI), and Palmer Drought Severity Index (PDSI).Both the satellite-based and in-situ methods revealed long-term declining trends in GWS and TWS across the country. These trends have been strongly influenced by climate change, leading to an intensification of evapotranspiration that surpasses total precipitation, rather than a decrease in precipitation itself.The study was conducted as part of the project GRANDE-U &amp;#8220;Groundwater Resilience Assessment through iNtegrated Data Exploration for Ukraine&amp;#8221; (NSF Awards No. 2409395 and 2409396).

An ozone budget for the UK: using measurements from the national ozone monitoring network; measured and modelled meteorological data, and a [formula omitted] resistance analogy model of dry deposition

Soils contain the largest terrestrial pool of carbon, and have large annual transfers of carbon with biomass pools and the atmosphere. Agricultural land use and management, and changes in climate have significant impacts on soil carbon, and if managed with conservation practices agricultural soils could be enhanced while sequestering carbon and mitigating greenhouse gas emissions. To better inform national climate change policy decisions for agricultural lands, robust and accurate estimates of soil organic carbon (SOC) stock changes are needed at regional to national scales. The design of a national soil monitoring network for carbon on agricultural lands is discussed including determination of sample size, allocation, and site-scale plot design. A quantitative case study is presented using modeled estimates of SOC stock change variability and a set of soil sample measurements to evaluate a potential network design for U.S. agricultural lands. Stratification by climate, soil, and land use with sites alloc...