Hydrology

22 pages, 4150 KiB

Open AccessArticle

Evaluating Trends and Insights from Historical Suspended Sediment and Land Management Data in the South Fork Clearwater River Basin, Idaho County, Idaho, USA

by Kevin M. Humphreys and David C. Mays

Hydrology 2025, 12(3), 50; https://doi.org/10.3390/hydrology12030050 - 6 Mar 2025

Abstract

In forested watersheds, suspended sediment concentration (SSC) is an important parameter that impacts water quality and beneficial use. Water quality also has impacts beyond the stream channel, as elevated SSC can violate Indigenous sovereignty, treaty rights, and environmental law. To address elevated SSC, [...] Read more.

In forested watersheds, suspended sediment concentration (SSC) is an important parameter that impacts water quality and beneficial use. Water quality also has impacts beyond the stream channel, as elevated SSC can violate Indigenous sovereignty, treaty rights, and environmental law. To address elevated SSC, watershed partners must understand the dynamics of the sediment regime in the basins they steward. Collection of additional data is expensive, so this study presents modeling and analysis techniques to leverage existing data on SSC. Using data from the South Fork Clearwater River in Idaho County, Idaho, USA, we modeled SSC over water years 1986–2011 and we applied regression techniques to evaluate correlations between SSC and natural disturbances (channel-building flow events) and anthropogenic disturbances (timber harvesting, hazardous fuel management, controlled burns, and wildfire). Analysis shows that SSC did not change over the period of record. This study provides a monitoring program design to support future decision making leading to reductions in SSC. Full article

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25 pages, 10057 KiB

Open AccessArticle

Machine Learning Analysis of Hydrological and Hydrochemical Data from the Abelar Pilot Basin in Abegondo (Coruña, Spain)

by Javier Samper-Pilar, Javier Samper-Calvete, Alba Mon, Bruno Pisani and Antonio Paz-González

Hydrology 2025, 12(3), 49; https://doi.org/10.3390/hydrology12030049 - 6 Mar 2025

Abstract

The Abelar pilot basin in Coruña (northwestern Spain) has been monitored for hydrological and hydrochemical data to assess the effects of eucalyptus plantation and manure applications on water resources, water quality, and nitrate contamination. Here, we report the machine learning analysis of hydrological [...] Read more.

The Abelar pilot basin in Coruña (northwestern Spain) has been monitored for hydrological and hydrochemical data to assess the effects of eucalyptus plantation and manure applications on water resources, water quality, and nitrate contamination. Here, we report the machine learning analysis of hydrological and hydrochemical data from the Abelar basin. K-means cluster analysis (CA) is used to relate nitrate concentrations at the outlet of the basin with daily interflows and groundwater flows calculated with a hydrological balance. CA identifies three linearly separable clusters. Times series Gaussian process regression (TS-GPR) is employed to predict surface water nitrate concentration by incorporating hydrological variables as additional input parameters using a time series shifting. TS-GPR allows modelling nitrate concentrations based on shifted interflows and groundwater flows and chemical concentrations with R² = 0.82 and 0.80 for training and testing, respectively. Groundwater flow from five days prior to the current date,

Q_{g 5}

, is the most important input parameter of the TS-GPR model. Interaction effects between the variables are found. TS-GPR validation with recent data provides results consistent with those of testing (R² = 0.85). Model inspection by permutation feature importance and partial dependence plots shows interactions between

Q_{g 5}

and Cl, and between Ca and Mg. Full article

(This article belongs to the Special Issue Novel Procedures and Methodologies for Surface and Underground Water Quality Analysis: Theory and Application)

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18 pages, 3127 KiB

Open AccessReview

Creation of Artificial Aeration System to Improve Water Quality in Reservoirs

by Artyom F. Khasanov and Anzhelika M. Eremeeva

Hydrology 2025, 12(3), 48; https://doi.org/10.3390/hydrology12030048 - 4 Mar 2025

Abstract

Hydroelectric power plants are widely used around the world, particularly in the countries of Central and South America. In Russia, there are more than 15 large hydroelectric power plants, which form the backbone of the country’s energy sector, providing about 20% of its [...] Read more.

Hydroelectric power plants are widely used around the world, particularly in the countries of Central and South America. In Russia, there are more than 15 large hydroelectric power plants, which form the backbone of the country’s energy sector, providing about 20% of its energy needs. The construction and operation of these plants take a long time, and it is important to plan carefully and minimize environmental damage during their use. The most significant factors affecting the environmental condition of reservoirs is the low oxygen content and the impossibility of water self-purification due to low water turbulence in deep layers. Coastal erosion caused by large hydroelectric dams can lead to increased land and population destruction, as well as sedimentation in reservoirs. The objective of this review was to select a method that would enhance the quality of water in the reservoirs of hydroelectric power stations. The technical solution that has been proposed is the implementation of the aeration of the reservoir and the cleaning of the aquatorium from sediments, with the aim of compensating for the damage caused by the construction of the dam. Full article

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29 pages, 27723 KiB

Open AccessArticle

A Geospatial Analysis Approach to Investigate Effects of Wildfires on Vegetation, Hydrological Response, and Recovery Trajectories in a Mediterranean Watershed

by Konstantinos Soulis, Stergia Palli Gravani, Rigas Giovos, Evangelos Dosiadis and Dionissios Kalivas

Hydrology 2025, 12(3), 47; https://doi.org/10.3390/hydrology12030047 - 4 Mar 2025

Abstract

Wildfires are frequently observed in watersheds with a Mediterranean climate and seriously affect vegetation, soil, hydrology, and ecosystems as they cause abrupt changes in land cover. Assessing wildfire effects, as well as the recovery process, is critical for mitigating their impacts. This paper [...] Read more.

Wildfires are frequently observed in watersheds with a Mediterranean climate and seriously affect vegetation, soil, hydrology, and ecosystems as they cause abrupt changes in land cover. Assessing wildfire effects, as well as the recovery process, is critical for mitigating their impacts. This paper presents a geospatial analysis approach that enables the investigation of wildfire effects on vegetation, soil, and hydrology. The prediction of regeneration potential and the period needed for the restoration of hydrological behavior to pre-fire conditions is also presented. To this end, the catastrophic wildfire that occurred in August 2021 in the wider area of Varybobi, north of Athens, Greece, is used as an example. First, an analysis of the extent and severity of the fire and its effect on the vegetation of the area is conducted using satellite imagery. The history of fires in the specific area is then analyzed using remote sensing data and a regrowth model is developed. The effect on the hydrological behavior of the affected area was then systematically analyzed. The analysis is conducted in a spatially distributed form in order to delineate the critical areas in which immediate interventions are required for the rapid restoration of the hydrological behavior of the basin. The period required for the restoration of the hydrological response is then estimated based on the developed vegetation regrowth models. Curve Numbers and post-fire runoff response estimations were found to be quite similar to those derived from measured data. This alignment shows that the SCS-CN method effectively reflects post-fire runoff conditions in this Mediterranean watershed, which supports its use in assessing hydrological changes in wildfire-affected areas. The results of the proposed approach can provide important data for the restoration and protection of wildfire-affected areas. Full article

(This article belongs to the Section Hydrological and Hydrodynamic Processes and Modelling)

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26 pages, 9680 KiB

Open AccessArticle

Development of Transient Hydrodynamic and Hydrodispesive Models in Semi-Arid Environments

by Samir Hakimi, Mohamed Abdelbaset Hessane, Mohammed Bahir, Turki Kh. Faraj and Paula M. Carreira

Hydrology 2025, 12(3), 46; https://doi.org/10.3390/hydrology12030046 - 3 Mar 2025

Abstract

The hydrogeological study of the Rharb coastal basin, located in the semi-arid northwest region of Morocco, focuses on its two aquifers: the Plio-Quaternary aquifer characterized by high-quality water with salt concentrations ranging from 0.4 to 2 g/L, and the Upper Quaternary aquifer, with [...] Read more.

The hydrogeological study of the Rharb coastal basin, located in the semi-arid northwest region of Morocco, focuses on its two aquifers: the Plio-Quaternary aquifer characterized by high-quality water with salt concentrations ranging from 0.4 to 2 g/L, and the Upper Quaternary aquifer, with lower water quality (2 to 6 g/L). The deep aquifer is overexploited for agricultural purposes. This overexploitation has led to declining piezometric levels and the worsening of the oceanic intrusion phenomenon. The study aims to develop a numerical model for a period of 15 years, from 1992/93 to 2006/07 for monitoring groundwater quantity and quality, considering recharge, exploitation, and basin characteristics. A hydrodynamic model based on storage coefficient calibration identifies overexploitation for irrigation, increasing from 93 Mm³ in 1993 to 170 Mm³ in 2007, as the primary driver of declining water levels. A hydrodispersive model highlights higher salt concentrations in the shallow aquifer (up to 6 g/L), high nitrate concentrations due to human activity, and pinpoints areas of seawater intrusion approximately 500 m from the shoreline. Although the deeper aquifer remains relatively preserved, negative hydraulic balances from −15.4 Mm³ in 1993 to −36.6 Mm³ in 2007 indicate an impending critical period. Full article

(This article belongs to the Special Issue Hydrological Modelling for the Sustainable Management of Water Resources in River Basins)

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17 pages, 3001 KiB

Open AccessArticle

Potentially Toxic Elements in Soils, Channel Banks, and Riverbed Sediments of a Watershed Under Agricultural Pressure

by Kamylla Gonçalves Oliveira Assis, Rennan Cabral Nascimento, Marcos Paulo Rodrigues Teixeira, Fernando Braga Rimá, Clístenes Williams Araújo do Nascimento, Cinthia Maria Cordeiro Atanázio Cruz Silva, Katerin Manuelita Encina Oliva, José Wellington Batista Lopes, Ronny Sobreira Barbosa, Vijay Pal Singh and Yuri Jacques Agra Bezerra da Silva

Hydrology 2025, 12(3), 45; https://doi.org/10.3390/hydrology12030045 - 27 Feb 2025

Abstract

Anthropogenic activities increase the amount of potentially toxic elements (PTEs) in the environment and consequently affect the quality of soils and water resources. This study aimed to investigate the concentrations, spatial distribution, and sources of soil and sediment pollution at the watershed scale [...] Read more.

Anthropogenic activities increase the amount of potentially toxic elements (PTEs) in the environment and consequently affect the quality of soils and water resources. This study aimed to investigate the concentrations, spatial distribution, and sources of soil and sediment pollution at the watershed scale for the following PTEs: aluminum (Al), barium (Ba), cerium (Ce), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), lanthanum (La), manganese (Mn), neodymium (Nd), nickel (Ni), lead (Pb), praseodymium (Pr), scandium (Sc), samarium (Sm), thorium (Th), titanium (Ti), vanadium (V), yttrium (Y) and zinc (Zn). One hundred and eighty-eight composite samples collected from preserved Cerrado areas, channel banks, agricultural areas, pastures, and riverbed sediments were used. Environmental contamination was assessed using geochemical indices and ecological risk assessment. The concentration of these elements often followed the order of riverbed sediment > channel bank > pasture > agricultural areas. Based on the pollutant load index, riverbed sediments and channel banks were classified as polluted, acting as a source of PTEs. The Gurgueia watershed, Brazil, was classified as unpolluted to moderately polluted, with low to no enrichment by PTEs. These values serve as a basis for future monitoring of the impacts resulting from the advance of agricultural and industrial activities in the region. Full article

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19 pages, 3487 KiB

Open AccessArticle

Evaluating the Effectiveness of Soil Profile Rehabilitation for Pluvial Flood Mitigation Through Two-Dimensional Hydrodynamic Modeling

by Julia Atayi, Xin Zhou, Christos Iliadis, Vassilis Glenis, Donghee Kang, Zhuping Sheng, Joseph Quansah and James G. Hunter

Hydrology 2025, 12(3), 44; https://doi.org/10.3390/hydrology12030044 - 26 Feb 2025

Abstract

Pluvial flooding, driven by increasingly impervious surfaces and intense storm events, presents a growing challenge for urban areas worldwide. In Baltimore City, MD, USA, climate change, rapid urbanization, and aging stormwater infrastructure are exacerbating flooding impacts, resulting in significant socio-economic consequences. This study [...] Read more.

Pluvial flooding, driven by increasingly impervious surfaces and intense storm events, presents a growing challenge for urban areas worldwide. In Baltimore City, MD, USA, climate change, rapid urbanization, and aging stormwater infrastructure are exacerbating flooding impacts, resulting in significant socio-economic consequences. This study evaluated the effectiveness of a soil profile rehabilitation scenario using a 2D hydrodynamic modeling approach for the Tiffany Run watershed, Baltimore City. This study utilized different extreme storm events, a high-resolution (1 m) LiDAR Digital Terrain Model (DTM), building footprints, and hydrological soil data. These datasets were integrated into a fully coupled 2D hydrodynamic model, the City Catchment Analysis Tool (CityCAT), to simulate urban flood dynamics. The pre-soil rehabilitation simulation revealed a maximum water depth of 3.00 m in most areas, with hydrologic soil groups C and D, especially downstream of the study area. The post-soil rehabilitation simulation was targeted at vacant lots and public parcels, accounting for 33.20% of the total area of the watershed. This resulted in a reduced water depth of 2.50 m. Additionally, the baseline runoff coefficient of 0.49 decreased to 0.47 following the rehabilitation, and the model consistently recorded a peak runoff reduction rate of 4.10 across varying rainfall intensities. The validation using a contingency matrix demonstrated true-positive rates of 0.75, 0.50, 0.64, and 0 for the selected events, confirming the model’s capability at capturing real-world flood occurrences. Full article

(This article belongs to the Special Issue Runoff Modelling under Climate Change)

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22 pages, 11656 KiB

Open AccessArticle

Hydrologic Decision Support in the Nile Basin: Creating Status Products from the GEOGLOWS Hydrologic Model

by Rachel Huber Magoffin, Riley C. Hales, E. James Nelson, Calvince Wara, Gustavious P. Williams, Andrew South and Zeleke K. Challa

Hydrology 2025, 12(3), 43; https://doi.org/10.3390/hydrology12030043 - 25 Feb 2025

Abstract

Effective decision-making in water resource management requires timely and reliable streamflow information. This study demonstrates how the GEOGLOWS Hydrologic Model, River Forecast System (RFS), can generate actionable hydrologic status products, focusing on a case study in the Nile River Basin. Through collaboration with [...] Read more.

Effective decision-making in water resource management requires timely and reliable streamflow information. This study demonstrates how the GEOGLOWS Hydrologic Model, River Forecast System (RFS), can generate actionable hydrologic status products, focusing on a case study in the Nile River Basin. Through collaboration with stakeholders at the Nile Basin Initiative (NBI), we identify key information needs and apply standardized low flow calculations, including the Standardized Streamflow Index (SSI) and the 95th percentile (Q95) threshold, to assess stream conditions. Additionally, we apply the World Meteorological Organization’s (WMO) Hydrologic Status and Outlook System (HydroSOS) method for streams and generate the associated HydroSOS-styled graphs and maps. We present the hydrologic status products in a customized web application for stakeholders in the Nile Basin. We discuss how RFS can be applied globally to provide hydrologic information. Full article

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20 pages, 5750 KiB

Open AccessArticle

Simulating Nonpoint Source Pollution Impacts in Groundwater: Three-Dimensional Advection–Dispersion Versus Quasi-3D Streamline Transport Approach

by Georgios Kourakos, Mehrdad Bastani and Thomas Harter

Hydrology 2025, 12(3), 42; https://doi.org/10.3390/hydrology12030042 - 24 Feb 2025

Abstract

Numerical models are commonly used to support the management of diffuse pollution sources in large agricultural landscapes. This paper investigates the suitability of a three-dimensional groundwater streamline-based nonpoint source (NPS) assessment tool for agricultural aquifers. The streamline approach is built on the assumption [...] Read more.

Numerical models are commonly used to support the management of diffuse pollution sources in large agricultural landscapes. This paper investigates the suitability of a three-dimensional groundwater streamline-based nonpoint source (NPS) assessment tool for agricultural aquifers. The streamline approach is built on the assumption of steady-state groundwater flow and neglects the effect of transverse dispersion but offers considerable computational efficiency. To test the practical applicability of these assumptions, two groundwater transport models were developed using the standard three-dimensional advection–dispersion equation (ADE): one with steady-state flow and the other with transient flow conditions. The streamline approach was compared with both ADE models, under various nitrate management practice scenarios. The results show that the streamline approach predictions are comparable to the steady-state ADE, but both steady-state methods tend to overestimate the concentrations across wells by up to 10% compared to the transient ADE. The prediction of long-term attenuation of nitrate under alternative land management scenarios is identical between the streamline and the transient ADE results. Full article

(This article belongs to the Section Hydrological and Hydrodynamic Processes and Modelling)

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18 pages, 3793 KiB

Open AccessArticle

Continuous Simulations for Predicting Green Roof Hydrologic Performance for Future Climate Scenarios

by Komal Jabeen, Giovanna Grossi, Michele Turco, Arianna Dada, Stefania A. Palermo, Behrouz Pirouz, Patrizia Piro, Ilaria Gnecco and Anna Palla

Hydrology 2025, 12(2), 41; https://doi.org/10.3390/hydrology12020041 - 19 Feb 2025

Abstract

Urban green spaces, including green roofs (GRs), are vital infrastructure for climate resilience, retaining water in city landscapes and supporting ecohydrological processes. Quantifying the hydrologic performance of GRs in the urban environment for future climate scenarios is the original contribution of this research [...] Read more.

Urban green spaces, including green roofs (GRs), are vital infrastructure for climate resilience, retaining water in city landscapes and supporting ecohydrological processes. Quantifying the hydrologic performance of GRs in the urban environment for future climate scenarios is the original contribution of this research developed within the URCA! project. For this purpose, a continuous modelling approach is undertaken to evaluate the hydrological performance of GRs expressed by means of the runoff volume and peak flow reduction at the event scale for long data series (at least 20 years). To investigate the prediction of GRs performance in future climates, a simple methodological approach is proposed, using monthly projection factors for the definition of future rainfall and temperature time series, and transferring the system parametrization of the current model to the future one. The proposed approach is tested for experimental GR sites in Genoa and Rende, located in Northern and Southern Italy, respectively. Referring to both the Genoa and Rende experimental sites, simulation results are analysed to demonstrate how the GR performance varies with respect to rainfall event characteristics, including total depth, maximum rainfall intensity and ADWP for current and future scenarios. Full article

(This article belongs to the Special Issue Soil–Water–City Nexus in Urban Environment: Experimental Investigations and Numerical Analysis in Urban Hydrology Science: 2nd Edition)

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12 pages, 1273 KiB

Open AccessArticle

Leaf Water Storage Capacity Among Eight US Hardwood Tree Species: Differences in Seasonality and Methodology

by Natasha Scavotto, Courtney M. Siegert, Heather D. Alexander and J. Morgan Varner

Hydrology 2025, 12(2), 40; https://doi.org/10.3390/hydrology12020040 - 18 Feb 2025

Abstract

Canopy hydrology and forest water inputs are directly linked to the physical properties of tree crowns (e.g., foliar and woody surfaces), which determine a tree’s capacity to intercept and retain incident rainfall. The changing forest structure, notably the decline of oak’s (Quercus [...] Read more.

Canopy hydrology and forest water inputs are directly linked to the physical properties of tree crowns (e.g., foliar and woody surfaces), which determine a tree’s capacity to intercept and retain incident rainfall. The changing forest structure, notably the decline of oak’s (Quercus) dominance and encroachment of non-oak species in much of the upland hardwood forests of the eastern United States, challenges our understanding of how species-level traits scale up to control the forest hydrologic budget. The objective of this study was to determine how the leaf water storage capacity varies across species and canopy layers, and how these relationships change throughout the growing season. We measured the leaf water storage capacity of overstory and midstory trees of native deciduous oaks (Q. alba, Q. falcata, Q. stellata) and non-oak species (Carya tomentosa, Acer rubrum, Ulmus alata, Liquidambar styraciflua, Nyssa sylvatica) using two methods (water displacement and rainfall simulation). Overstory Q. alba leaves retained 0.5 times less water per unit leaf area than other overstory species (p < 0.001) in the early growing season, while in the late growing season, C. tomentosa leaves had the lowest storage capacity (p = 0.024). Quercus falcata leaves displayed a minimal change in storage between seasons, while Q. alba and Q. stellata leaves had higher water storage in the late growing season. Midstory U. alata leaves had 3.5 times higher water storage capacity in the early growing season compared to all the other species (p < 0.001), but this difference diminished in the late growing season. Furthermore, the water storage capacities from the simulated rainfall experiments were up to two times higher than those in the water displacement experiments, particularly during the early growing season. These results underscore the complexity of leaf water storage dynamics, the methodology, and the implications for forest hydrology and species interactions. Broader efforts to understand species-level controls on canopy water portioning through leaf and other crown characteristics are necessary. Full article

(This article belongs to the Section Ecohydrology)

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42 pages, 2991 KiB

Open AccessReview

Event-Based vs. Continuous Hydrological Modeling with HEC-HMS: A Review of Use Cases, Methodologies, and Performance Metrics

by Golden Odey and Younghyun Cho

Hydrology 2025, 12(2), 39; https://doi.org/10.3390/hydrology12020039 - 17 Feb 2025

Abstract

This study critically examines the applications of the Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) in hydrological research from 2000 to 2023, with a focus on its use in event-based and continuous simulations. A bibliometric analysis reveals a steady growth in research productivity and [...] Read more.

This study critically examines the applications of the Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) in hydrological research from 2000 to 2023, with a focus on its use in event-based and continuous simulations. A bibliometric analysis reveals a steady growth in research productivity and identifies key thematic areas, including hydrologic modeling, climate change impact assessment, and land use analysis. Event-based modeling, employing methods such as the SCS curve number (CN) and SCS unit hydrograph, demonstrates exceptional performance in simulating short-term hydrological responses, particularly in flood risk management and stormwater applications. In contrast, continuous modeling excels in capturing long-term processes, such as soil moisture dynamics and groundwater contributions, using methodologies like soil moisture accounting and linear reservoir baseflow approaches, which are critical for water resource planning and climate resilience studies. This review highlights the adaptability of HEC-HMS, showcasing its successful integration of event-based precision and continuous process modeling through hybrid approaches, enabling robust analyses across temporal scales. By synthesizing methodologies, performance metrics, and case studies, this study offers practical insights for selecting appropriate modeling techniques tailored to specific hydrological objectives. Moreover, it identifies critical research gaps, including the need for advanced calibration methods, enhanced parameter sensitivity analyses, and improved integration with hydraulic models. These findings highlight HEC-HMS’s critical role in improving hydrological research and give a thorough foundation for its use in addressing current water resource concerns. Full article

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25 pages, 8413 KiB

Open AccessArticle

Flood Exposure Dynamics and Quantitative Evaluation of Low-Cost Flood Control Measures in the Bengawan Solo River Basin of Indonesia

by Badri Bhakta Shrestha, Mohamed Rasmy and Daisuke Kuribayashi

Hydrology 2025, 12(2), 38; https://doi.org/10.3390/hydrology12020038 - 17 Feb 2025

Abstract

The frequent occurrence of floods puts additional pressure on people to change their activities and alter land use practices, consequently making exposed lands more vulnerable to floods. It is thus crucial to investigate dynamic changes in flood exposures and conduct quantitative evaluations of [...] Read more.

The frequent occurrence of floods puts additional pressure on people to change their activities and alter land use practices, consequently making exposed lands more vulnerable to floods. It is thus crucial to investigate dynamic changes in flood exposures and conduct quantitative evaluations of flood risk-reduction strategies to minimize damage to exposed items. This study quantitatively assessed dynamics of flood exposure and flood risk, and evaluated the effectiveness of flood control measures in the Bengawan Solo River basin, Indonesia. The Water and Energy Budget-Based Rainfall–Runoff–Inundation Model was employed for flood simulation for different return periods, and then dynamics of flood exposures and flood risk were assessed. After that, the effectiveness of flood control measures was quantitively evaluated. The results show that settlement/built-up areas and population are increasing in flood-prone areas. The flood-exposed paddy field and settlement areas for 100-year flood were estimated to be more than 950 and 212.58 km², respectively. The results also show that the dam operation for flood control in the study area reduces the flood damage to buildings, contents, and agriculture by approximately 21.2%, 20.9%, and 25.1%, respectively. The river channel improvements were also found effective to reduce flood damage in the study area. The flood damage can be reduced by more than 60% by implementing a combination of a flood control dam and river channel improvements. The findings can be useful for planning and implementing effective flood risk reduction measures. Full article

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29 pages, 14374 KiB

Open AccessArticle

Assessment of Heavy Metals in Surface Waters of the Santiago–Guadalajara River Basin, Mexico

by Rosa Leonor González-Díaz, José de Anda, Harvey Shear, Luis Eduardo Padilla-Tovar, Ofelia Yadira Lugo-Melchor and Luis Alberto Olvera-Vargas

Hydrology 2025, 12(2), 37; https://doi.org/10.3390/hydrology12020037 - 17 Feb 2025

Abstract

The Santiago–Guadalajara River Basin has an area of 10,016.46 km². The Metropolitan Area of Guadalajara, within the basin, is the second-largest city in the country, with more than 5 million inhabitants. The growth of the urban population, as well as industrial [...] Read more.

The Santiago–Guadalajara River Basin has an area of 10,016.46 km². The Metropolitan Area of Guadalajara, within the basin, is the second-largest city in the country, with more than 5 million inhabitants. The growth of the urban population, as well as industrial and agricultural activities with insufficient infrastructure for the sanitation of wastewater and its reuse, have caused environmental deterioration of surface waters and gradual depletion of groundwater resources. To assess the level of contamination in surface waters from the presence of heavy metals in the basin, a monthly monitoring campaign was carried out at 25 sampling stations located in the main and tributary streams from July 2021 to April 2022. The following decreasing sequence was found according to the mean concentration values: Fe > Al > Mn > B > Ba > Zn > As > Cu > Cr > Ni > Pb > Cd. The Heavy Metal Pollution Index (HPI) method was applied to assess the level of risk to aquatic life, finding an average global HPI value of 305.522 for the basin, which classifies it as in the critical contamination range. The results also reflect health risks due to the presence of As, Cd, and Ni in some monitored stations. It will be necessary to expand the monitoring network, identify the point and non-point sources of contamination, and implement measures for pollution control to protect aquatic life and human health due to the presence of heavy metals in the river. Full article

(This article belongs to the Special Issue Hydrodynamics and Water Quality of Rivers and Lakes)

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22 pages, 2068 KiB

Open AccessArticle

Determination of the Total Phosphorus Decay Coefficient Based on Hydrological Models in an Artificial Reservoir in the Brazilian Semi-Arid Region

by Francisco Josivan de Oliveira Lima, Fernando Bezerra Lopes, Daniel Antônio Camelo Cid, Iran Eduardo Lima Neto, Renan Vieira Rocha, Alyson Brayner Sousa Estácio, Isabel Cristina da Silva Araújo, Nayara Rochelli de Sousa Luna, Michele Cunha Pontes, Arthur Costa Tomaz de Souza and Eunice Maia de Andrade

Hydrology 2025, 12(2), 36; https://doi.org/10.3390/hydrology12020036 - 16 Feb 2025

Abstract

Phosphorus input into surface water is a global concern due to its role in eutrophication, which is especially critical in semi-arid regions with their challenging climatic conditions. This study evaluated the best model for estimating the phosphorus decay coefficient (k) in semi-arid lakes, [...] Read more.

Phosphorus input into surface water is a global concern due to its role in eutrophication, which is especially critical in semi-arid regions with their challenging climatic conditions. This study evaluated the best model for estimating the phosphorus decay coefficient (k) in semi-arid lakes, using flows from the Soil Moisture Accounting Procedure (SMAP), model of Génie Rural à 4 paramètres Journalier (GR4J), and reverse water balance hydrological models. Conducted at the Orós reservoir with 37 sampling campaigns from 2008 to 2017, it compared decay rates for temperate, tropical, and semi-arid climates. Some analyses also used phosphorus concentrations measured at the reservoir inlet. Model efficiency was assessed with bias, mean relative error, mean squared error, root mean squared error, and standard deviation. from the best models, water quality classes were classified based on phosphorus concentrations with the use of a confusion matrix to calculate accuracy, precision, recall, and F1 score. The findings demonstrated that the decay rate tailored for semi-arid regions, when combined with GR4J flow data, offered the highest accuracy in estimating phosphorus concentrations (bias = 0.0012, RMSE = 0.0326, EMR = 60.6134, STD = 0.0312). In contrast, the decay rate calibrated for tropical conditions with SMAP-derived flows proved superior for classifying water quality categories (classes defined by CONAMA Resolution 357/05). Therefore, the GR4J model for semi-arid conditions stands out for concentration estimation, while the tropical decay rate with SMAP flows is preferable for effective classification of water quality status. Full article

(This article belongs to the Special Issue Hydrodynamics and Water Quality of Rivers and Lakes)

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27 pages, 7459 KiB

Open AccessArticle

Flood Modelling of the Zhabay River Basin Under Climate Change Conditions

by Aliya Nurbatsina, Zhanat Salavatova, Aisulu Tursunova, Iulii Didovets, Fredrik Huthoff, María-Elena Rodrigo-Clavero and Javier Rodrigo-Ilarri

Hydrology 2025, 12(2), 35; https://doi.org/10.3390/hydrology12020035 - 15 Feb 2025

Abstract

Flood modelling in snow-fed river basins is critical for understanding the impacts of climate change on hydrological extremes. The Zhabay River in northern Kazakhstan exemplifies a basin highly vulnerable to seasonal floods, which pose significant risks to infrastructure, livelihoods, and water resource management. [...] Read more.

Flood modelling in snow-fed river basins is critical for understanding the impacts of climate change on hydrological extremes. The Zhabay River in northern Kazakhstan exemplifies a basin highly vulnerable to seasonal floods, which pose significant risks to infrastructure, livelihoods, and water resource management. Traditional flood forecasting in Central Asia still relies on statistical models developed during the Soviet era, which are limited in their ability to incorporate non-stationary climate and anthropogenic influences. This study addresses this gap by applying the Soil and Water Integrated Model (SWIM) to project climate-driven changes in the hydrological regime of the Zhabay River. The study employs a process-based, high-resolution hydrological model to simulate flood dynamics under future climate conditions. Historical hydrometeorological data were used to calibrate and validate the model at the Atbasar gauge station. Future flood scenarios were simulated using bias-corrected outputs from an ensemble of General Circulation Models (GCMs) under Representative Concentration Pathways (RCPs) 4.5 and 8.5 for the periods 2011–2040, 2041–2070, and 2071–2099. This approach enables the assessment of seasonal and interannual variability in flood magnitudes, peak discharges, and their potential recurrence intervals. Findings indicate a substantial increase in peak spring floods, with projected discharge nearly doubling by mid-century under both climate scenarios. The study reveals a 1.8-fold increase in peak discharge between 2010 and 2040, and a twofold increase from 2041 to 2070. Under the RCP 4.5 scenario, extreme flood events exceeding a 100-year return period (2000 m³/s) are expected to become more frequent, whereas the RCP 8.5 scenario suggests a stabilization of extreme event occurrences beyond 2071. These findings underscore the growing flood risk in the region and highlight the necessity for adaptive water resource management strategies. This research contributes to the advancement of climate-resilient flood forecasting in Central Asian river basins. The integration of process-based hydrological modelling with climate projections provides a more robust framework for flood risk assessment and early warning system development. The outcomes of this study offer crucial insights for policymakers, hydrologists, and disaster management agencies in mitigating the adverse effects of climate-induced hydrological extremes in Kazakhstan. Full article

(This article belongs to the Section Hydrological and Hydrodynamic Processes and Modelling)

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24 pages, 10495 KiB

Open AccessArticle

Dependence of Soil Moisture and Strength on Topography and Vegetation Varies Within a SMAP Grid Cell

by Joseph R. Bindner, Holly Proulx, Kevin Wickham, Jeffrey D. Niemann, Joseph Scalia IV, Timothy R. Green and Peter J. Grazaitis

Hydrology 2025, 12(2), 34; https://doi.org/10.3390/hydrology12020034 - 15 Feb 2025

Abstract

Off-road vehicle mobility assessments rely on fine-resolution (~10 m) estimates of soil moisture and strength across the region of interest. Such estimates are often produced by downscaling soil moisture from a microwave satellite like SMAP, then using the soil moisture in a soil [...] Read more.

Off-road vehicle mobility assessments rely on fine-resolution (~10 m) estimates of soil moisture and strength across the region of interest. Such estimates are often produced by downscaling soil moisture from a microwave satellite like SMAP, then using the soil moisture in a soil strength model. Soil moisture downscaling methods typically assume consistent relationships between the moisture and topographic, vegetation, and soil composition characteristics within the microwave satellite grid cells. The objective of this study is to examine whether soil moisture and strength exhibit heterogenous dependencies on topography, vegetation, and soil composition characteristics within a SMAP grid cell. Soil moisture and strength data were collected at four geographically separated regions within a 9 km SMAP grid cell in the Front Range foothills of northern Colorado. Laboratory methods and pedotransfer functions were used to characterize soil attributes, and remote sensing data were used to determine topographic and vegetation attributes. Pearson correlation analyses were used to quantify the direction, strength, and significance of the relationships of both soil moisture and strength with topography, vegetation, and soil composition. Contrary to the common assumption, spatial variations in the slope and correlation of the relationships are observed for both soil moisture and strength. The findings indicate that improved predictions of soil moisture and soil strength may be achievable by soil moisture downscaling procedures that use spatially variable parameters across the downscaling extent. Full article

(This article belongs to the Section Soil and Hydrology)

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21 pages, 4483 KiB

Open AccessArticle

DEM Generation Incorporating River Channels in Data-Scarce Contexts: The “Fluvial Domain Method”

by Jairo R. Escobar Villanueva, Jhonny I. Pérez-Montiel and Andrea Gianni Cristoforo Nardini

Hydrology 2025, 12(2), 33; https://doi.org/10.3390/hydrology12020033 - 14 Feb 2025

Abstract

This paper presents a novel methodology to generate Digital Elevation Models (DEMs) in flat areas, incorporating river channels from relatively coarse initial data. The technique primarily utilizes filtered dense point clouds derived from SfM-MVS (Structure from Motion-Multi-View Stereo) photogrammetry of available crewed aerial [...] Read more.

This paper presents a novel methodology to generate Digital Elevation Models (DEMs) in flat areas, incorporating river channels from relatively coarse initial data. The technique primarily utilizes filtered dense point clouds derived from SfM-MVS (Structure from Motion-Multi-View Stereo) photogrammetry of available crewed aerial imagery datasets. The methodology operates under the assumption that the aerial survey was carried out during low-flow or drought conditions so that the dry (or almost dry) riverbed is detected, although in an imprecise way. Direct interpolation of the detected elevation points yields unacceptable river channel bottom profiles (often exhibiting unrealistic artifacts) and even distorts the floodplain. In our Fluvial Domain Method, channel bottoms are represented like “highways”, perhaps overlooking their (unknown) detailed morphology but gaining in general topographic consistency. For instance, we observed an 11.7% discrepancy in the river channel long profile (with respect to the measured cross-sections) and a 0.38 m RMSE in the floodplain (with respect to the GNSS-RTK measurements). Unlike conventional methods that utilize active sensors (satellite and airborne LiDAR) or classic topographic surveys—each with precision, cost, or labor limitations—the proposed approach offers a more accessible, cost-effective, and flexible solution that is particularly well suited to cases with scarce base information and financial resources. However, the method’s performance is inherently limited by the quality of input data and the simplification of complex channel morphologies; it is most suitable for cases where high-resolution geomorphological detail is not critical or where direct data acquisition is not feasible. The resulting DEM, incorporating a generalized channel representation, is well suited for flood hazard modeling. A case study of the Ranchería river delta in the Northern Colombian Caribbean demonstrates the methodology. Full article

(This article belongs to the Special Issue Hydrological Modeling and Sustainable Water Resources Management)

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16 pages, 3161 KiB

Open AccessArticle

Eutrophication Conditions in Two High Mountain Lakes: The Influence of Climate Conditions and Environmental Pollution

by Fátima Goretti García-Miranda, Claudia Muro, Yolanda Alvarado, José Luis Expósito-Castillo and Héctor Víctor Cabadas-Báez

Hydrology 2025, 12(2), 32; https://doi.org/10.3390/hydrology12020032 - 13 Feb 2025

Abstract

The lakes known as El Sol and La Luna are high mountain water deposits located in Mexico within an inactive volcanic system. These lakes are of ecological importance because they are unique in Mexico. However, currently, the lakes have experienced changes in their [...] Read more.

The lakes known as El Sol and La Luna are high mountain water deposits located in Mexico within an inactive volcanic system. These lakes are of ecological importance because they are unique in Mexico. However, currently, the lakes have experienced changes in their shape and an increase in algae blooms, coupled with the degradation of the basin, which has alerted government entities to the need to address the lakes’ problems. To address the environmental status of El Sol and La Luna, a trophic study was conducted during the period of 2021–2023, including an analysis of the influence of climatic variables, lake water quality, and eutrophication conditions. The trophic state was established based on the eutrophication index. The Pearson correlations defined the eutrophication interrelation between the distinct factors influencing the lakes’ status. El Sol registered higher eutrophication conditions than La Luna. El Sol was identified as seasonal eutrophic and La Luna as transitioning from oligotrophic to mesotrophic, showing high levels of chlorophyll, total phosphorus, and total nitrogen and low water transparency. The principal factors altering the eutrophic conditions were water pollution and climatic variables (precipitation and ambient temperature). Eutrophication was the prime factor impacting perimeter loss at El Sol, whereas at La Luna, it was due to a decline in precipitation. Full article

(This article belongs to the Topic Advances in Hydrological Remote Sensing)

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