Water-level Maps Research Articles

Evaluating SWOT's interferometric capabilities for mapping intertidal topography

The Surface Water and Ocean Topography (SWOT) mission, originally designed for observing ocean and inland water bodies, can be a valuable tool for mapping the topography of intertidal flats. This study provides the first demonstration of SWOT's ability to measure intertidal topography using simultaneous interferometric acquisitions. Observations acquired between April and July 2023, during the calibration/validation (CALVAL) phase of the mission, were used. SWOT-derived intertidal Digital Elevation Models (DEMs) were generated from level-2 High-Rate Pixel Cloud (L2_HR_PIXC) products and compared to airborne and UAV LiDAR-derived DEMs. Our results indicate a high reliability of the SWOT observations with a mean absolute error lower than 0.49 m, reaching 0.13 m in specific areas. This validation confirms SWOT's contribution for coastal studies beyond water level mapping, showcasing its broader applicability in the monitoring and management of coastal and estuarine environments.

Quantification of surface water extent and volume in the Inner Niger Delta (IND) over 2000–2022 using multispectral imagery and radar altimetry

Spatio-temporal dynamics of surface water reservoirs at regional and global scales remain poorly understood. Using satellite remote sensing provides a unique opportunity to address this problem. This study aims to (1) quantify the extent and volume of surface water and (2) compare our approach with other datasets. We utilized MODIS-based spectral indices to monitor temporal variations in inundation extent. By interpolating water levels across the surface water extent, we generated water level maps and quantified surface water volume from 2000 to 2022. Evaluation against ICESat-2 data involved 64 comparisons, with approximately 58% showing an R 2 value greater than or equal to 0.5, and 38% were higher than or equal to 0.7. Compared to the flooding model, our method aligns more closely with ICESat-2 data, contrary to the flooding model which tends to overestimate water levels and, consequently, water storage.

Hydrological Analysis of Khargone Area, Khargone District, Madhya Pradesh, India

The paper is focused on hydrogeological analysis Khargone area, Khargone District, Madhya Pradesh, India. The study area typically consists of basalt rock formations dating from the Late Cretaceous to the Paleocene era of the Deccan Traps. The alluvium is clearly visible along the Kunda River's course. The hydrogeological examination of 70 open dug wells reveals well diameter range between 3 meters and 9 meters, Depth of well within the range of 6-7 m.b.g.l. Static water levels ranged from 1 m. to 17 m.b.g.l. The fluctuation ranges between 2 to 12 m respectively. The ground water level maps of post and pre monsoon periods indicate that in general the ground water movement is towards the kunda River. The suitable sites for ground water development have been suggested in the villages of Nangalda, Ibrampura, Thibgaon Khurd and Dongargaon.

Comparing Flood Damages to an Industrial Region in Turkey Using Several Methods

Floods are one of the disasters that cause the greatest damage to social life, living health, economy and environment. This paper reveals the calculation of the economic damage of the commercial areas located near the creek due to floods in Sakarya, Dinsiz Stream. In this study, first, flood propagation maps were produced according to 50, 100, 200 and 500 years of flood flow periods that may occur in the study area. The HECRAS program was used to produce the flood maps and a 2D model was created from these maps, water level maps were obtained and then depth damage curves were used to figure out the economic losses leading to flood. In addition to the Huizinga, van Eck and Kok, ICBR, Pistrika and Jonkman flood damage assessment methods, which are frequently used in the literature, the HAZUS-MH method was used to calculate the economic losses that may occur in commercial areas. While HAZUS has functions that make separate calculations for each commercial sector, in other methods, calculations are made over the total area without sector discrimination. In addition, HAZUS has more detailed ranges of flooding water depths and therefore the calculation of damage rates corresponding to water depths can be done with higher precision than other methods. According to the data obtained as a result of the study, the losses exceeded million euros in all methods, while the highest values were in the Pistrika and Jonkman methods.

Quantizing Rare Random Maps: Application to Flooding Visualization

Visualization is an essential operation when assessing the risk of rare events such as coastal or river floodings. The goal is to display a few prototype events that best represent the probability law of the observed phenomenon, a task known as quantization. It becomes a challenge when data is expensive to generate and critical events are scarce, like extreme natural hazard. In the case of floodings, each event relies on an expensive-to-evaluate hydraulic simulator which takes as inputs offshore meteo-oceanic conditions and dyke breach parameters to compute the water level map. In this article, Lloyd’s algorithm, which classically serves to quantize data, is adapted to the context of rare and costly-to-observe events. Low probability is treated through importance sampling, while Functional Principal Component Analysis combined with a Gaussian process deal with the costly hydraulic simulations. The calculated prototype maps represent the probability distribution of the flooding events in a minimal expected distance sense, and each is associated to a probability mass. The method is first validated using a 2D analytical model and then applied to a real coastal flooding scenario. The two sources of error, the metamodel and the importance sampling, are evaluated to quantify the precision of the method. Supplementary materials for this article are available online.

Super-Resolution by Fusing Multispectral and Terrain Models: Application to Water Level Mapping

Super-Resolution by Fusing Multispectral and Terrain Models: Application to Water Level Mapping

Evaluation of water-level trends in the Mimbres Basin, southwest New Mexico (USA), using spatiotemporal kriging

Groundwater-level trends over the past 40 years in the Mimbres Basin of southwest New Mexico (USA) were characterized with sequential water-level maps and maps of water-level change generated via spatiotemporal kriging. In the region of the most abundant irrigated agriculture, water levels have declined up to 24 m and cones of depression have expanded greatly. Increases in area of irrigated land and groundwater withdrawals in the past 10 years are coeval with water-level declines near the USA-Mexico border. Known areas of groundwater recharge from streamflow infiltration, and springs discharging deep-sourced water, show evidence of net water-level rises in the past 40 years, but declines in the last 10 years, in concert with declining precipitation over the basin. Formerly irrigated lands exhibit water-level rises, suggestive of flattening of cones of depression after cessation of extensive groundwater pumping. Manual water-level measurements are vital for understanding and managing groundwater resources, yet they are expensive and laborious to collect, which has resulted in much fewer data in recent years. Spatiotemporal kriging is more complex in mathematical development and implementation than spatial kriging, but it yields improved precision and accuracy, predictions at times with no data as well as at locations with no data, and fewer artifacts due to changing well networks. Its ability to leverage historical data recommends its use in hydrologic studies dependent on water-level maps and changes in water levels over time.

Water Level Change Monitoring Based on a New Denoising Algorithm Using Data from Landsat and ICESat-2: A Case Study of Miyun Reservoir in Beijing

Inland lakes or reservoirs are the main surface water resources, related to people’s survival and social development. On-site water level data are critical for water resource management, while satellite laser and remote sensing data are a significant tool for long-term change monitoring. In this study, we took the Miyun Reservoir, the most important source of drinking water in Beijing, as the research area. We used Landsat images and the Ice, Cloud, and Land Elevation Satellite (ICESat-2) for small-scale water level change monitoring and inversion across unrecorded periods. First, we proposed a new two-step denoising method based on local statistics to denoise the ATL03 single photon data from 2018 to 2020, and extracted the effective elevation information of Miyun Reservoir. Second, based on Landsat images from 1984 to 2020, the MNDWI index was used to extract the water area and generated a percentage map of water occurrence. Finally, the water and land boundary elevation were selected from the effective photon elevation information according to the boundary position under each percentage of the water generation percentage graph, the area, and the water level elevation model (A–E model) was established, and the water level values of unrecorded periods were inverted. The denoising results showed that the denoising accuracy of all data is higher than 95%. The area of Miyun Reservoir has changed greatly in the past 37 years, especially in the northeast corner and northern region. The inverted water level elevation had a strong correlation with the measured value, the correlation coefficient reached 0.97, the root mean square error (RMSE) was 0.553 m, and the estimated water level value was highly consistent with the recorded value and fluctuated dramatically from 1984 to 2020. This method complements the traditional water level mapping method, provides a new idea for the monitoring of water level changes in lakes or reservoirs without field records, and also contributes to the timely and effective monitoring and management of global lake and reservoir water level and time changes.

Salinity Contributions from Geothermal Waters to the Rio Grande and Shallow Aquifer System in the Transboundary Mesilla (United States)/Conejos-Médanos (Mexico) Basin

Freshwater scarcity has raised concerns about the long-term availability of the water supplies within the transboundary Mesilla (United States)/Conejos-Médanos (Mexico) Basin in Texas, New Mexico, and Chihuahua. Analysis of legacy temperature data and groundwater flux estimates indicates that the region’s known geothermal systems may contribute more than 45,000 tons of dissolved solids per year to the shallow aquifer system, with around 8500 tons of dissolved solids being delivered from localized groundwater upflow zones within those geothermal systems. If this salinity flux is steady and eventually flows into the Rio Grande, it could account for 22% of the typical average annual cumulative Rio Grande salinity that leaves the basin each year—this salinity proportion could be much greater in times of low streamflow. Regional water level mapping indicates upwelling brackish waters flow towards the Rio Grande and the southern part of the Mesilla portion of the basin with some water intercepted by wells in Las Cruces and northern Chihuahua. Upwelling waters ascend from depths greater than 1 km with focused flow along fault zones, uplifted bedrock, and/or fractured igneous intrusions. Overall, this work demonstrates the utility of using heat as a groundwater tracer to identify salinity sources and further informs stakeholders on the presence of several brackish upflow zones that could notably degrade the quality of international water supplies in this developed drought-stricken region.

Localized Scenarios and Latitudinal Patterns of Vertical and Lateral Resilience of Tidal Marshes to Sea‐Level Rise in the Contiguous United States

AbstractCoastal wetlands have two dimensions of vulnerability to sea‐level rise (SLR), a vertical one, in cases where SLR outpaces their capacity to vertically accrete, and a lateral one, in cases where they are restricted from migrating inland by topography and land use. We conducted a meta‐analysis of accretion rates, standardized our analysis by using only 137Cs based estimates, and used model intercomparison to generate a vertical resilience index, a function of local SLR, tidal range, and tidal elevation category for the tidal wetlands of the contiguous US. We paired the vertical resilience index with a lateral resilience index made up of elevation, water level, and land cover maps, then projected them both into the future using localized SLR scenarios. At the regional scale, the vertical resilience index predicts changes from marsh aggradation to submergence for the coastal US Mid‐Atlantic, Southeast, and portions of the Northeast by 2100. At the sub‐regional scale, there is a geographic tradeoff between vertical and lateral resilience with more northerly wetlands vulnerable to the lack of suitable proportional area to migrate into, and more southerly wetlands vulnerable to accretion deficit. We estimate between 43% and 48% of the existing contiguous US wetland area, almost entirely located in watersheds along the Gulf of Mexico and Mid‐Atlantic coasts, is subject to both vertical and lateral limitations. These vertical and lateral resilience indices could help direct future research, planning, and mitigation efforts at a national scale, as well as supplement more processed informed approaches by local planners and practitioners.

Development of a Simulation Model for Real-Time Urban Floods Warning: A Case Study at Sukhumvit Area, Bangkok, Thailand

Increasingly frequent, high-intensity rain events associated with climatic change are driving urban drainage systems to function beyond their design discharge capacity. It has become an urgent issue to mitigate the water resource management challenge. To address this problem, a real-time procedure for predicting the inundation risk in an urban drainage system was developed. The real-time procedure consists of three components: (i) the acquisition and forecast of rainfall data; (ii) rainfall-runoff modeling; and (iii) flood inundation mapping. This real-time procedure was applied to a drainage system in the Sukhumvit area of Bangkok, Thailand, to evaluate its prediction efficacy. The results showed precisely that the present real-time procedure had high predictability in terms of both the water level and flood inundation area mapping. It could also determine hazardous areas with a certain amount of lead time in the drainage system of the Sukhumvit area within an hour of rainfall data. These results show the real-time procedure could provide accurate flood risk warning, resulting in more time to implement flood management measures such as pumping and water gate operations, or evacuation.

Structural control on the occurrence of groundwater in granite gneissic terrain, Purulia, West Bengal

Purulia, one of the most drought prone districts of West Bengal, India, is geologically a part of Chotanagpur Gneissic Complex and is mainly a granite gneissic terrain. Scarcity of drinking water has always been a major concern in the area. Thus, a hydrogeological study was carried out in and around Purulia I and Purulia II blocks of the district during lean season. The main objective of the study is to determine the structural control on groundwater flow so that groundwater extraction can be optimised economically in the area. For the purpose, depth to water level zonation map was prepared with flow direction. The lineament data was obtained by analysing satellite imagery of the area and was cross-checked using field data. The orientation of the major joint sets is NE-SW and NW-SE in this area. The NW-SE trending fractures act as conduits and facilitate the flow, while NE-SW trending fractures act as an obstruction to the flow. The lineament density of the area was overlaid on depth to water level map using Surfer and it is observed where fractures form a network, water occurs at shallow level, while in places where fractures are isolated, water flows down to deeper levels. It was interpreted from all the observations that the flow of groundwater in this area depends on the distribution of joints, thus subsurface water being structurally controlled. This type of study has been carried out in various parts of the world but in Purulia district of West Bengal, India, structural control on the occurrence of subsurface water has not yet been established through any major studies. This study will help in divulging structural control on groundwater in this area and identification of areas where constructing tubewells will help in economical extraction of groundwater.

Hydrochemical studies and evaluation of groundwater quality of the Quaternary aquifer at Faquss, Al Sharqiya Governorate, Egypt

The Quaternary deposits represent the main groundwater aquifer in the study area. During the last few years, the problem of groundwater contamination has been intensified mainly due to natural and human-related factors. The present work aims to study the hydrochemical characteristics and quality assessment of shallow groundwater of the Quaternary aquifer at Faquss district. To achieve that, 16 groundwater samples were collected and analyzed for major ions, trace elements, and microbiological analysis. Constructions of water level map of the Pleistocene aquifer and distribution maps for different ions in groundwater were made by surfer software. Statistical analyses for water quality parameters were carried out. Results indicate that most of the studied area is characterized by fresh water (TDS < 1000 mg/L) with low contents of K, Na, Mg, Ca, SO4, and Cl reflecting the suitability of ground water for drinking. High contents of TDS, Na, SO4, and Cl are recorded at the northeastern parts of the area; this refers to the existence of local pollution sources resulting from the infiltration of domestic, agricultural, and industrial wastes in the intensive populated area. The concentrations of trace elements (chromium, copper, cadmium, etc.) in groundwater are within the acceptable limits for drinking and domestic uses. Iron and manganese are over the acceptable limits in most of the area and the groundwater is unsuitable for drinking. Low contents of iron and manganese are recorded at the north, while aluminum contents are over the acceptable limits at the same site. The results of bacteriological analyses indicate the existence of E. coli bacteria in most of shallow wells ranges between 4 and 800 ml. So, shallow groundwater should be chemically treated before drinking. Generally, the groundwater in the studied area is suitable for irrigation, except 19% of wells suffer from sodium hazards. The ratio rNa/rCl varies between 1.012 and 1.56 in most groundwater samples and indicates the continental origin of groundwater in the study area. The ratio r (K + Na)-rCl/rSO4 reflects either Na2–SO4 water type (in 75% of groundwater samples) or NaHCO3 water type of shallow meteoric origin (in 25% of groundwater samples). The presence of Na2SO4 water type in deep meteoric water genesis at shallow depth is associated with sulfate salts (MgSO4, and CaSO4) which formed more than 25% of salt combination might reflect the influence of anthropogenic activities. The dominant process determining the water composition is evaporation.

Preliminary Investigations for Landfill Siting in Lafia, Nasarawa State of Central Nigeria

Waste management has taken the front purview in recent years due to the evident and attendant effects of indiscriminate disposal of wastes to the environment. This led to the preliminary investigations for the proposed siting of a landfill facility in Lafia and environs of Nasarawa State in Central Nigeria, with the aim of providing valuable information on the suitability for location for the disposal of Municipal Solid Waste (MSW). The combined use of geo-resistivity, geological and hydrogeological investigations were carried out for the study. Ten Vertical Electrical Soundings (VES) of the Schlumberger array was used to investigate the properties of the subsurface lithologies to determine their properties especially, clay, for siting a landfill. Clay, an attenuating material, is significant for siting a landfill facility because it tends to isolate potentially toxic wastes from the environment by slowing down the movement of leachates into groundwater and the environmental. Quantitative interpretation of data of the VES survey using the IPI2win computer software revealed the presence of four to five geologic layers comprising of sandy top soil (247 – 1964Ωm), silty sand (98 – 3488Ωm), clayey-shally/sand (68 – 3922Ωm), saturated clayey sand (31 – 3226Ωm) and loose sand (478Ωm). Clay was found to be abundant in the area and found at depths ranging from 30m to infinity. Geologically, structures like lineaments abound and were analysed; they show a dominant trend in the NW – SE direction from the Rosette Diagram. Lineaments are useful for studies because they are possible conduits where decomposed wastes in liquid form, such as leachates, get transported to pollute groundwater. Hydrogeological studies surveyed Static Water Levels (SWL) measurement from 51 hand dug wells in the study area. The SWL ranges between 5.8m and 37.1m. The data from the SWL was used to construct the absolute water level map in a 3D form to show the flow direction of the groundwater. The study revealed the presence of impermeable clays at VES 1, 2, 3, 9 and 10. This is significant for selection for landfill due to its pollution-prevention properties of groundwater pollution. The investigations carried out in this study show that Shabu, a town located about 8km from Lafia, is likely suitable for siting a landfill facility; because of the abundance of clay at a shallow depth of 30m and with limited preponderance of lineaments.

Inter-aquifer connectivity between Australia’s Great Artesian Basin and the overlying Condamine Alluvium: an assessment and its implications for the basin’s groundwater management

Coal seam gas (CSG), or coal bed methane, developments in sedimentary basins such as the Great Artesian Basin (GAB) in Australia, have the potential to impact on aquifers overlying and underlying the target coal formations. The extent to which this may occur depends upon the degree of hydrogeological connectivity between the coal formations and the surrounding aquifers or aquifer systems, with general implications for groundwater management. In southeast Australia, one such aquifer system, the Condamine Alluvium (CA), overlies the Walloon Coal Measures (WCM), which is a formation of the GAB and also a target for CSG production. To investigate the connectivity between the two systems, multiple lines of investigation were employed involving field investigations, data gathering and analysis (including reinterpretation of geology, multivariate hydrochemistry analysis, regional water-level mapping, drilling and coring across the contact zone, multiple piezometer installations, long-term pumping tests, groundwater-level monitoring and local-scale modelling). The study found a low level of connectivity between the GAB and the overlying CA. A layer of undifferentiated basement clay (referred to as the ‘transition zone’)—a mixture of alluvial clay and weathered basement—provides an effective impediment to flow across the CA and the underlying GAB formations. Results from the study potentially have wider application across the GAB and sedimentary basins where younger alluvial sediments associated with river systems frequently overlie the erosional surface.

Identification of Soil Contamination using VLF-EM and Resistivity Methods: A Case Study

Hazardous waste is a waste with properties which can pollute and damage the environment, human health, and other living things. Lakardowo is a village that is suspected of being contamination by hazardous waste derived from industrial activities. Measurements with the VLF-EM and Resistivity method were used in this study. In addition, ground water level mapping and soil sampling in locations around the industry were conducted for the XRF test. Groundwater mapping results show that groundwater flow lead to the Northeast-South and Southwest of the industrial site. The soil samples that have been tested by XRF show the presence of heavy metals, wherein hazardous wastes generally contain various types of heavy metals that are conductive or have low resistivity values. Quantitative interpretation of VLF-EM data shows the presence of low resistivity anomalies at several measurement sites, which are suspected to have been contaminated with soil by waste. Resistivity data processing results, showing a low resistivity anomaly (≤ 3 Ω.m) located to the north (near an industrial site) and spreading towards the southwest along the measurement path. The result of a combination of quantitative interpretations of both methods, obtained, the direction of anomalous flow of hazardous waste moves southeastward and towards deeper soil coating following the direction of rock coating.

Analysis of Groundwater Balance in Well Irrigation Over Exploitation Area of Liaocheng City

In order to study the influence of water level dynamic factors in the over-extraction area of well irrigation, hydrogeological surveys were carried out in the over-extraction area and outside the well-poor area, and data were collected to make equal water level maps for different years from 2011 to 2015. The well water level map was determined according to the water level map. The scope of groundwater balance analysis in the mining area analyzes the groundwater balance in the area of 85.23km2, 79.3km2 and 62.15km2 of the groundwater over-exploitation area in Guanxian, Shenxian and Linqing, respectively, and calculates the groundwater recharge and excretion in each district from 2011 to 2015 year. As well as the shallow groundwater storage variables, it is concluded that the groundwater balance in the Liaocheng Guanxian, Shenxian and Linqing well irrigation over-exploitation areas in 2011∼2015 years is negatively balanced.

Analyzing depletion of groundwater level using operations management and control

PurposeThe analysis of groundwater level below the earth surface is focused on current and future scenarios. To analyze the wells under the threat of water level depletion, a study is conducted on the groundwater level using control charts. To improve watershed management, the important criteria are to increase infiltration as well as water storage capacity. There are 15 over-exploited zones in the study area (Dynamic GW Resources 2011). The purpose of this paper is to help in understanding the importance of wells for improving the water level to a certain extent for sustainable development.Design/methodology/approachThe water levels in the wells are located with the help of x, y, z plotting on the ground using ArcGIS software. This water level mapping is done at a micro-watershed level to increase the clarity of information at the micro-level. In this study, the problem of depleted wells is sorted out, and the water level present in depleted wells pre-monsoon and post-monsoon is evaluated for the two years. Also, water level analysis is done using a control chart to find out the critical wells. On the basis of Poisson distribution, C-chart is used here to analyze the quality of wells and the water levels in those wells to be improved.FindingsThe outcome of the C-chart helps to track the wells that can be improved further to increase the water level. This paper presents the study of estimation of appropriate sites to be given importance and the rate of water level depletion to be controlled, which also helps to select a site suitable for artificial restoration by targeting groundwater potential zones.Originality/valueThis paper gives an outlook idea of wells that can be improved and the area that should be given more attention. Analyzing water level depletion helps to identify a suitable site for groundwater restoration using a remote sensing and geographical information system. These measures help the government and public sectors for proper planning and management of natural resources.

Satellite-based estimates of surface water dynamics in the Congo River Basin

In the Congo River Basin (CRB), due to the lack of contemporary in situ observations, there is a limited understanding of the large-scale variability of its present-day hydrologic components and their link with climate. In this context, remote sensing observations provide a unique opportunity to better characterize those dynamics. Analyzing the Global Inundation Extent Multi-Satellite (GIEMS) time series, we first show that surface water extent (SWE) exhibits marked seasonal patterns, well distributed along the major rivers and their tributaries, and with two annual maxima located: i) in the lakes region of the Lwalaba sub-basin and ii) in the “Cuvette Centrale”, including Tumba and Mai-Ndombe Lakes. At an interannual time scale, we show that SWE variability is influenced by ENSO and the Indian Ocean dipole events. We then estimate water level maps and surface water storage (SWS) in floodplains, lakes, rivers and wetlands of the CRB, over the period 2003–2007, using a multi-satellite approach, which combines the GIEMS dataset with the water level measurements derived from the ENVISAT altimeter heights. The mean annual variation in SWS in the CRB is 81 ± 24 km3 and contributes to 19 ± 5% of the annual variations of GRACE-derived terrestrial water storage (33 ± 7% in the Middle Congo). It represents also ∼6 ± 2% of the annual water volume that flows from the Congo River into the Atlantic Ocean.

Delineation of groundwater potential zone in hard rock terrain in Gangajalghati block, Bankura district, India using remote sensing and GIS techniques

This study employed with the integration of remote sensing (RS) and geographical information system (GIS) techniques to delineate ground water potential zones for ground water management of Gangajalghati block, Bankura district, West Bengal and is located on the eastern slope of Chotanagpur plateau and area belongs to predominantly Precambrian gneissic terrain, and small area belongs to Gondwana deposits and quaternary sediments. The groundwater in this region is confined within the weathered residuum and fracture zones in pediment region. Survey of India topographical maps and satellite imageries along with other data and field observation data have been utilized to prepare various thematic layers viz. drainage, slope, lineament, geology, hydrogeomorphic units, land-use/land cover, soil, and depth to water level map of this hard rock terrain. All the thematic map that influence ground water occurrences have been analyzed and integrated through GIS analysis based on weights assignment. The weighted index overlay method has been followed to delineate ground water potential zones. The result revealed that the study area can be categorized into four different ground water potential zones viz., very good, good, moderate, and poor zones. The bore well yield data reveals that medium yielding wells (50–100 L per min) are in and around the moderate to high lineament density zone and buried pediment medium region. Afterward validation with well yield data revealed a good correlation with respect to the observed ground water potential zonation. This study is useful for better planning and management of ground water resources as well as providing quick prospective guides for ground water exploration in hard rock aquifer system.