Hydrology

26 pages, 2541 KiB

Open AccessArticle

A Comparative Study of Potential Evapotranspiration Estimation by Three Methods with FAO Penman–Monteith Method across Sri Lanka

by Himasha Dilshani Abeysiriwardana, Nitin Muttil and Upaka Rathnayake

Hydrology 2022, 9(11), 206; https://doi.org/10.3390/hydrology9110206 - 21 Nov 2022

Cited by 7 | Viewed by 2593

Abstract

Among numerous methods that have been developed to estimate potential evapotranspiration (PET), the Food and Agricultural Organization Penman–Monteith model (FAO P–M) is often recognized as a standard method to estimate PET. This study was conducted to evaluate the applicability of three other PET [...] Read more.

Among numerous methods that have been developed to estimate potential evapotranspiration (PET), the Food and Agricultural Organization Penman–Monteith model (FAO P–M) is often recognized as a standard method to estimate PET. This study was conducted to evaluate the applicability of three other PET estimation methods, i.e., Shuttleworth–Wallace (S–W) model, Thornthwaite (TW) and pan methods, to estimate PET across Sri Lanka with respect to the FAO P–M model. The meteorological data, i.e., temperature, relative humidity, wind speed, net solar radiation, and pan evaporation, recorded at 14 meteorologic stations, representing all climate and topographic zones of Sri Lanka, were obtained from 2009 to 2019. The models’ performances were assessed based on three statistical indicators: root mean squared error (RMSE), bias, and Pearson correlation coefficient (R). In comparison with the FAO P–M model estimates, the seasonal and annual estimates of all three models show great differences. The results suggested that pan and S–W methods perform better in the dry zone of the country. Both S–W and pan methods underestimated PET over the entire county in all seasons. TW does not show consistent results over the country, thus being found as the least reliable alternative. Although S–W is highly correlated with the FAO P–M model, the application of the model in a data-scarce region is more constrained, as it requires more parameters than the FAO P–M model. Thus, the study suggests employing alternative methods based on the region of the country instead of one single method across the entire country. Full article

(This article belongs to the Special Issue Advances in Evaporation and Evaporative Demand: Part II)

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27 pages, 5594 KiB

Open AccessArticle

Insight into Hurricane Maria Peak Daily Streamflows from the Development and Application of the Precipitation-Runoff Modeling System (PRMS): Including Río Grande de Arecibo, Puerto Rico, 1981–2017

by Eric D. Swain and Jason C. Bellino

Hydrology 2022, 9(11), 205; https://doi.org/10.3390/hydrology9110205 - 21 Nov 2022

Cited by 1 | Viewed by 1310

Abstract

The Precipitation-Runoff Modeling System (PRMS) was used to develop a simulation of watershed hydrology on the island of Puerto Rico for the period 1981–2017, concentrating on the Río Grande de Arecibo, a river with some of the highest streamflows on the island. This [...] Read more.

The Precipitation-Runoff Modeling System (PRMS) was used to develop a simulation of watershed hydrology on the island of Puerto Rico for the period 1981–2017, concentrating on the Río Grande de Arecibo, a river with some of the highest streamflows on the island. This development is part of the U.S. Geological Survey’s (USGS) National Hydrologic Model (NHM) infrastructure which supports coordinated, comprehensive, and consistent hydrologic modeling at the watershed scale for the coterminous United States (CONUS). A goal of the NHM program is to expand the domain outside of CONUS, leading to a PRMS application in Puerto Rico. This model was used to simulate the effects of Hurricane Maria on daily streamflow and provide information at locations where streamgages were damaged by the hurricane. Comparisons with streamflow estimates made by indirect methods in the field, up to ten times higher than simulated values, lends insight into the uncertainties in both the indirect methods and model simulated values and helps to identify potential error in the daily streamflow estimates. The PRMS can be applied to look at the effects of changes in climate and land use, water management, industrial and public water usage, and many other factors that affect hydrology on the island of Puerto Rico. The model is also designed as a support tool for the USGS National Water Census which provides comprehensive reporting of national information on withdrawal, conveyance, consumptive use, and return flow by water-use category. Full article

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

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23 pages, 6327 KiB

Open AccessArticle

Evaluation of Long-Term Radar-Derived Precipitation for Water Balance Estimates: A Case Study for Multiple Catchments in Saxony, Germany

by Thanh Thi Luong, Ivan Vorobevskii, Judith Pöschmann, Rico Kronenberg, Daniel Gliksman and Christian Bernhofer

Hydrology 2022, 9(11), 204; https://doi.org/10.3390/hydrology9110204 - 20 Nov 2022

Viewed by 1321

Abstract

Quality of water balance estimations are strongly dependent on the precipitation input. The key limitation here is typically a lack of spatial representation in precipitation data. Quantitative precipitation estimation (QPE) using radar is recognized as capable to significantly enhance the spatial representation of [...] Read more.

Quality of water balance estimations are strongly dependent on the precipitation input. The key limitation here is typically a lack of spatial representation in precipitation data. Quantitative precipitation estimation (QPE) using radar is recognized as capable to significantly enhance the spatial representation of precipitation compared to conventional rain gauge-based methods by calibrating radar pixels with surrounding rain gauges. However, the measured precipitation is often underestimated due to wind drift or funnel evaporation, particularly in mountainous areas. Thus, a post-correction is required before applying radar precipitation in water balance models. Here, we applied the Richter correction for the first time to a radar-based QPE, to model the water balance in ten catchments in Saxony, Germany. The hydrological responses for the period 2001–2017 from the model were validated with discharge observations. The results show that radar data application yielded reliable simulations of water balance (KGE = 0.53 and 0.70 at daily and monthly resolutions, respectively). However, a simple compensation such as the Richter method to conventional precipitation should be used with caution. This study shows that radar-based precipitation has immense potential to advance quality of the precipitation input to distributed hydrologic models not only for flood events but also for climatological analyses. Full article

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22 pages, 2644 KiB

Open AccessEditor’s ChoiceReview

Perspective Impact on Water Environment and Hydrological Regime Owing to Climate Change: A Review

by Mohsin Abbas, Linshuang Zhao and Yanning Wang

Hydrology 2022, 9(11), 203; https://doi.org/10.3390/hydrology9110203 - 14 Nov 2022

Cited by 8 | Viewed by 4751

Abstract

This study summarizes reviews on climate change’s impact on the water environment and hydrological regime. The results indicate a strong relationship between the climatological parameters and hydrological patterns. This relationship can be determined in two steps: (1) define the variations in climatological factors, [...] Read more.

This study summarizes reviews on climate change’s impact on the water environment and hydrological regime. The results indicate a strong relationship between the climatological parameters and hydrological patterns. This relationship can be determined in two steps: (1) define the variations in climatological factors, particularly temperature and precipitation, and (2) measure the variations in runoff and inflows to streams and river systems using different statistical and global climate modeling approaches. It is evident that the increasing global temperatures have significant positive effects on runoff variations and evapotranspiration. Similarly, the increase in temperature has speeded up the melting of glaciers and ice on hilly terrains. This is causing frequent flash floods and a gradual rise in the sea level. These factors have altered the timing of stream flow into rivers. Furthermore, the accumulation of greenhouse gases, variations in precipitation and runoff, and sea-level rise have significantly affected freshwater quality. These effects are likely to continue if timely mitigation and adaptation measures are not adopted. Full article

(This article belongs to the Special Issue Climate Change Effects on Hydrology and Water Resources)

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21 pages, 4144 KiB

Open AccessArticle

Exploring Temporal Dynamics of River Discharge Using Univariate Long Short-Term Memory (LSTM) Recurrent Neural Network at East Branch of Delaware River

by Md Abdullah Al Mehedi, Marzieh Khosravi, Munshi Md Shafwat Yazdan and Hanieh Shabanian

Hydrology 2022, 9(11), 202; https://doi.org/10.3390/hydrology9110202 - 11 Nov 2022

Cited by 21 | Viewed by 2724

Abstract

River flow prediction is a pivotal task in the field of water resource management during the era of rapid climate change. The highly dynamic and evolving nature of the climatic variables, e.g., precipitation, has a significant impact on the temporal distribution of the [...] Read more.

River flow prediction is a pivotal task in the field of water resource management during the era of rapid climate change. The highly dynamic and evolving nature of the climatic variables, e.g., precipitation, has a significant impact on the temporal distribution of the river discharge in recent days, making the discharge forecasting even more complicated for diversified water-related issues, e.g., flood prediction and irrigation planning. In order to predict the discharge, various physics-based numerical models are used using numerous hydrologic parameters. Extensive lab-based investigation and calibration are required to reduce the uncertainty involved in those parameters. However, in the age of data-driven predictions, several deep learning algorithms showed satisfactory performance in dealing with sequential data. In this research, Long Short-term Memory (LSTM) neural network regression model is trained using over 80 years of daily data to forecast the discharge time series up to seven days ahead of time. The performance of the model is found satisfactory through the comparison of the predicted data with the observed data, visualization of the distribution of the errors, and R2 value of 0.93 with one day lead time. Higher performance is achieved through the increase in the number of epochs and hyperparameter tuning. This model can be transferred to other locations with proper feature engineering and optimization to perform univariate predictive analysis and potentially be used to perform real-time river discharge prediction. Full article

(This article belongs to the Special Issue Traditional Statistics vs. Modern Machine Learning Approaches in Hydrology)

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22 pages, 9056 KiB

Open AccessArticle

Differentiated Spatial-Temporal Flood Vulnerability and Risk Assessment in Lowland Plains in Eastern Uganda

by Godwin Erima, Isa Kabenge, Antony Gidudu, Yazidhi Bamutaze and Anthony Egeru

Hydrology 2022, 9(11), 201; https://doi.org/10.3390/hydrology9110201 - 09 Nov 2022

Cited by 5 | Viewed by 2475

Abstract

This study was conducted to map flood inundation areas along the Manafwa River, Eastern Uganda using HECRAS integrated with the SWAT model. The study mainly sought to evaluate the predictive capacity of SWAT by comparisons with streamflow observations and to derive, using HECRAS, [...] Read more.

This study was conducted to map flood inundation areas along the Manafwa River, Eastern Uganda using HECRAS integrated with the SWAT model. The study mainly sought to evaluate the predictive capacity of SWAT by comparisons with streamflow observations and to derive, using HECRAS, the flood inundation maps. Changes in Land-use/cover showed by decrease in forest areas and wetlands, and conversions into farmlands and built-up areas from 1995 to 2017 have resulted in increased annual surface runoff, sediment yield, and water yield. Flood frequency analysis for 100-, 50-, 10-, and 5-year return periods estimated peak flows of 794, 738, 638, and 510 m³/s, respectively, and total inundated areas of 129, 111, 101, and 94 km², respectively. Hazard classification of flood extent indicated that built-up areas and commercial farmlands are highly vulnerable, subsistence farmlands are moderately to highly vulnerable, and bushland, grassland, tropical high forest, woodland, and wetland areas are very low to moderately vulnerable to flooding. Results demonstrated the usefulness of combined modeling systems in predicting the extent of flood inundation, and the developed flood risk maps will enable the policy makers to mainstream flood hazard assessment in the planning and development process for mitigating flood hazards. Full article

(This article belongs to the Special Issue Modern Developments in Flood Modelling)

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14 pages, 1392 KiB

Open AccessArticle

Water Quality in a Small Lowland River in Different Land Use

by Beata Rutkowska, Wieslaw Szulc, Wiktor Wyżyński, Katarzyna Gościnna, Stanislav Torma, Jozef Vilček and Štefan Koco

Hydrology 2022, 9(11), 200; https://doi.org/10.3390/hydrology9110200 - 08 Nov 2022

Cited by 3 | Viewed by 1998

Abstract

The paper describes water quality in the Raszynka River based on selected chemical parameters dependent on different land use. The research was carried out in the Raszynka River catchment, characterized by a small surface area (75.9 km²) and length (17.14 km). [...] Read more.

The paper describes water quality in the Raszynka River based on selected chemical parameters dependent on different land use. The research was carried out in the Raszynka River catchment, characterized by a small surface area (75.9 km²) and length (17.14 km). The river is a right tributary of the Utrata River. It is located in the Piaseczno and Pruszkow districts in the Mazowieckie voivodship. The dominant type of land use in the basin is agricultural land. Water samples were collected from 2017 to 2019 from previously designated research points at similar distances along the river. Selected physicochemical indicators examined in the samples include total alkalinity, electrolytic conductivity (EC), pH, and chemical oxygen demand (COD). Moreover, the concentration of selected substances was determined, including nitrogen compounds: NO₃⁻ (nitrates) and NH₄⁺ (ammonium), TP (total phosphorus), and Cl⁻ (chlorides). The results showed that the values of some of the examined indicators do not meet the standards set for first-class surface water quality. Indicators significantly exceeding the limit included ammonium, chlorides, and pH. The highest concentration of chlorides, ammonium, and nitrate was found in urbanized areas. The highest concentrations of total phosphorus and COD were determined in agricultural areas and total alkalinity in meadows. Full article

(This article belongs to the Special Issue Advances in Land Surface Hydrological Processes)

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27 pages, 5674 KiB

Open AccessEditor’s ChoiceArticle

The Spatial Scale Dependence of The Hurst Coefficient in Global Annual Precipitation Data, and Its Role in Characterising Regional Precipitation Deficits within a Naturally Changing Climate

by Enda O’Connell, Greg O’Donnell and Demetris Koutsoyiannis

Hydrology 2022, 9(11), 199; https://doi.org/10.3390/hydrology9110199 - 07 Nov 2022

Cited by 2 | Viewed by 4567

Abstract

Hurst’s seminal characterisation of long-term persistence (LTP) in geophysical records more than seven decades ago continues to inspire investigations into the Hurst phenomenon, not just in hydrology and climatology, but in many other scientific fields. Here, we present a new theoretical development based [...] Read more.

Hurst’s seminal characterisation of long-term persistence (LTP) in geophysical records more than seven decades ago continues to inspire investigations into the Hurst phenomenon, not just in hydrology and climatology, but in many other scientific fields. Here, we present a new theoretical development based on stochastic Hurst–Kolmogorov (HK) dynamics that explains the recent finding that the Hurst coefficient increases with the spatial scale of averaging for regional annual precipitation. We also present some further results on the scale dependence of H in regional precipitation, and reconcile an apparent inconsistency between sample results and theory. LTP in average basin scale precipitation is shown to be consistent with LTP in the annual flows of some large river basins. An analysis of the crossing properties of precipitation deficits in regions exhibiting LTP shows that the Hurst coefficient can be a parsimonious descriptor of the risk of severe precipitation deficits. No evidence is found for any systematic trend in precipitation deficits attributable to anthropogenic climate change across the regions analysed. Future precipitation deficit risk assessments should, in the first instance, be based on stochastic HK simulations that encompass the envelope of uncertainty synonymous with LTP, and not rely exclusively on GCM projections that may not properly capture long-term natural variability in the climate. Some views and opinions are expressed on the implications for policy making in sustainable water resources management. Full article

(This article belongs to the Collection Feature Papers of Hydrology)

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19 pages, 3414 KiB

Open AccessArticle

Factors Affecting Runoff and Sediment Load Changes in the Wuding River Basin from 1960 to 2020

by Yin Chen, Pei Zhang, Ying Zhao, Liqin Qu, Pengfei Du and Yangui Wang

Hydrology 2022, 9(11), 198; https://doi.org/10.3390/hydrology9110198 - 05 Nov 2022

Cited by 2 | Viewed by 2217

Abstract

To investigate changes in runoff and sediment load in the Wuding River basin under the combined influence of climate change and human activities, trends were analyzed from 1960 to 2020, and the contribution rate of climate change and human activities was calculated. It [...] Read more.

To investigate changes in runoff and sediment load in the Wuding River basin under the combined influence of climate change and human activities, trends were analyzed from 1960 to 2020, and the contribution rate of climate change and human activities was calculated. It was observed that the runoff and sediment load Mann–Kendall test value ranges at eight gauging stations were −7.42 to −3.88 and −9.28 to −3.34, respectively, indicating a significant decreasing trend in both. During the period of 1970–2000, the contribution of human activities to the reduction in runoff and sediment load was 69.9% and 75.3%, respectively. However, the impact of human activities intensified after 2001 due to the implementation of the policy of returning farmland to forests in the Wuding River basin, which contributed to 118.4% and 114.5% of the reduction in runoff and sediment load, respectively. Check dam and reservoir construction, reforestation, water diversion, and other human activities were all important factors in runoff and sediment load reduction. In particular, the total sediment retention by reservoirs in the Wuding River basin was approximately 879 million tons until 2010, and the total sediment retention by check dams was approximately 2747 million t until 2017. This study can provide support for the utilization of water resources and the construction of ecological civilization in the Wuding River basin, and can also provide a reference for the study of water and sediment changes in other basins. Full article

(This article belongs to the Special Issue Recent Advances in Water and Water Resources Engineering)

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21 pages, 6637 KiB

Open AccessEditor’s ChoiceArticle

Long Term Trend Analysis of River Flow and Climate in Northern Canada

by Mohamed Sherif Zaghloul, Ebrahim Ghaderpour, Hatef Dastour, Babak Farjad, Anil Gupta, Hyung Eum, Gopal Achari and Quazi K. Hassan

Hydrology 2022, 9(11), 197; https://doi.org/10.3390/hydrology9110197 - 04 Nov 2022

Cited by 16 | Viewed by 3386

Abstract

Changes in water resources within basins can significantly impact ecosystems, agriculture, and biodiversity, among others. Basins in northern Canada have a cold climate, and the recent changes in climate can have a profound impact on water resources in these basins. Therefore, it is [...] Read more.

Changes in water resources within basins can significantly impact ecosystems, agriculture, and biodiversity, among others. Basins in northern Canada have a cold climate, and the recent changes in climate can have a profound impact on water resources in these basins. Therefore, it is crucial to study long term trends in water flow as well as their influential factors, such as temperature and precipitation. This study focused on analyzing long term trends in water flow across the Athabasca River Basin (ARB) and Peace River Basin (PRB). Long term trends in temperature and precipitation within these basins were also studied. Water flow data from 18 hydrometric stations provided by Water Survey of Canada were analyzed using the Mann-Kendall test and Sen’s slope. In addition, hybrid climate data provided by Alberta Environment and Parks at approximately 10 km spatial resolution were analyzed for the ARB and its surrounding regions during 1950–2019. Trend analysis was performed on the water flow data on monthly, seasonal, and annual scales, and the results were cross-checked with trends in temperature and precipitation and land use and land cover data. The overall temperature across the basins has been increasing since 1950, while precipitation showed an insignificant decrease during this period. Winter water flow in the upper ARB has been slowly and steadily increasing since 1956 because of the rising temperatures and the subsequent slow melting of snowpacks/glaciers. The warm season flows in the middle and lower subregions declined up to 1981, then started to show an increasing trend. The middle and lower ARB exhibited a rapid increase in warm-season water flow since 2015. A similar trend change was also observed in the PRB. The gradual increase in water flow observed in the recent decades may continue by the mid-century, which is beneficial for agriculture, forestry, fishery, and industry. However, climate and land cover changes may alter the trend of water flow in the future; therefore, it is important to have a proper management plan for water usage in the next decades. Full article

(This article belongs to the Section Hydrology–Climate Interactions)

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18 pages, 3566 KiB

Open AccessEditor’s ChoiceArticle

nZVI Mobility and Transport: Laboratory Test and Numerical Model

by Paolo Viotti, Giuseppe Sappa, Fabio Tatti and Francesca Andrei

Hydrology 2022, 9(11), 196; https://doi.org/10.3390/hydrology9110196 - 03 Nov 2022

Cited by 3 | Viewed by 1709

Abstract

Zerovalent iron nanoparticles (nZVI) are becoming one of the most widely recommended nanomaterials for soil and groundwater remediation. However, when nZVI are injected in the groundwater flow, the behavior (mobility, dispersion, distribution) is practically unknown. This fact generally results in the use of [...] Read more.

Zerovalent iron nanoparticles (nZVI) are becoming one of the most widely recommended nanomaterials for soil and groundwater remediation. However, when nZVI are injected in the groundwater flow, the behavior (mobility, dispersion, distribution) is practically unknown. This fact generally results in the use of enormous quantities of them at the field scale. The uncertainties are on the effective volumes reached from the plume of nZVI because their tendency to aggregate and their weight can cause their settling and deposition. So, the mobility of nanoparticles is a real issue, which can often lead to inefficient or expensive soil remediation. Furthermore, there is another aspect that must be considered: the fate of these nZVI in the groundwater and their possible impact on the subsoil environment. All these considerations have led us to propose an application of nZVI simulating the permeation technique through a laboratory experience, finalized to have a better, or even simpler description of their real behavior when injected in a flow in the subsoil. A two-dimensional laboratory-scale tank was used to study the dispersion and transport of nZVI. A nZVI solution, with a concentration equal to 4.54 g/L, was injected into glass beads, utilized as porous medium. The laboratory experiment included a digital camera to acquire the images. The images were then used for calibrating a numerical model. The results of the mass balance confirm the validity of the proposed numerical model, obtaining values of velocity (5.41 × 10⁻³ m/s) and mass (1.9 g) of the nZVI of the same order of those from the experimental tests. Several information were inferred from both experimental and numerical tests. Both demonstrate that nZVI plume does not behave as a solute dissolved in water, but as a mass showing its own mobility ruled mainly from the buoyancy force. A simple simulation of a tracer input and a nZVI plume are compared to evidence the large differences between their evolution in time and space. This means that commercial numerical models, if not corrected, cannot furnish a real forecast of the volume of influence of the injected nZVI. Further deductions can be found from the images and confirmed by means the numerical model where the detachment effect is much smaller than the attachment one (ratio k_d/k_a = 0.001). From what is reported, it is worthwhile to pay attention on the localization of the contaminants source/plume to reach an effective treatment and it is important to go further in the improvement of solution for the limiting the nanoparticles aggregation phenomenon. Full article

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22 pages, 4991 KiB

Open AccessEditor’s ChoiceArticle

Structuralization of Complicated Lotic Habitats Using Sentinel-2 Imagery and Weighted Focal Statistic Convolution

by Yang Liu and Mei-Po Kwan

Hydrology 2022, 9(11), 195; https://doi.org/10.3390/hydrology9110195 - 31 Oct 2022

Viewed by 1504

Abstract

Deriving the proper structure of lotic habitats, namely the structuralization of lotic habitats, is crucial to monitoring and modeling water quality on a large scale. How to structuralize complicated lotic habitats for practical use remains challenging. This study novelly integrates remote sensing, geographic [...] Read more.

Deriving the proper structure of lotic habitats, namely the structuralization of lotic habitats, is crucial to monitoring and modeling water quality on a large scale. How to structuralize complicated lotic habitats for practical use remains challenging. This study novelly integrates remote sensing, geographic information system (GIS), and computer vision techniques to structuralize complicated lotic habitats. A method based on Sentinel-2 imagery and weighted focal statistic convolution (WFSC) is developed to structuralize the complicated lotic habitats into discrete river links. First, aquatic habitat image objects are delineated from Sentinel-2 imagery using geographic object-based image analysis (GEOBIA). These lotic habitat image objects are then separated from lentic habitat image objects using a hydrologically derived river network as a reference. Second, the binary image of the lotic habitat image objects is converted to a fuzzy magnitude surface using WFSC. The ridgelines on the magnitude surface are traced as the centerlines of river links. Finally, the centerlines of river links are used to split the complicated lotic habitats into discrete river links. Essential planar geometric attributes are then numerically derived from each river link. The proposed method was successfully applied to the braided river network in the Mobile River Basin in the U.S. The results indicate that the proposed method can properly structuralize lotic habitats with high spatial accuracy and correct topological consistency. The proposed method can also derive essential attributes that are difficult to obtain from conventional methods on a large scale. With sufficient measurements, a striking width–abundance pattern has been observed in our study area, indicating a promising logarithmic law in lotic habitat abundance. Full article

(This article belongs to the Special Issue Advances in River Monitoring)

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17 pages, 16645 KiB

Open AccessFeature PaperArticle

Identifying Modelling Issues through the Use of an Open Real-World Flood Dataset

by Vasilis Bellos, Ioannis Kourtis, Eirini Raptaki, Spyros Handrinos, John Kalogiros, Ioannis A. Sibetheros and Vassilios A. Tsihrintzis

Hydrology 2022, 9(11), 194; https://doi.org/10.3390/hydrology9110194 - 31 Oct 2022

Cited by 6 | Viewed by 1829

Abstract

The present work deals with the reconstruction of the flood wave that hit Mandra town (Athens, Greece) on 15 November 2017, using the framework of forensic hydrology. The flash flood event was caused by a huge storm event with a high level of [...] Read more.

The present work deals with the reconstruction of the flood wave that hit Mandra town (Athens, Greece) on 15 November 2017, using the framework of forensic hydrology. The flash flood event was caused by a huge storm event with a high level of spatial and temporal variability, which was part of the Medicane Numa-Zenon. The reconstruction included: (a) the post-event collection of 44 maximum water depth traces in the town; and (b) the hydrodynamic simulation employing the HEC-RAS and MIKE FLOOD software. The derived open dataset (which also includes additional data required for hydrodynamic modeling) is shared with the community for possible use as a benchmark case for flood model developers. With regards to the modeling issues, we investigate the calibration strategies in computationally demanding cases, and test whether the calibrated parameters can be blindly transferred to another simulator (informed modeling). Regarding the calibration, it seems that the coupling of an initial screening phase with a simple grid-search algorithm is efficient. On the other hand, the informed modeling concept does not work for our study area: every numerical model has its own dynamics while the parameters are of grey-box nature. As a result, the modeler should always be skeptical about their global use. Full article

(This article belongs to the Special Issue Modern Developments in Flood Modelling)

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22 pages, 7363 KiB

Open AccessArticle

Flood Exposure Assessment and Mapping: A Case Study for Australia’s Hawkesbury-Nepean Catchment

by Mark Ziegelaar and Yuriy Kuleshov

Hydrology 2022, 9(11), 193; https://doi.org/10.3390/hydrology9110193 - 29 Oct 2022

Cited by 5 | Viewed by 2918

Abstract

Floods are the most common and costliest natural disaster in Australia. However, the Flood Risk Assessments (FRAs) employed to manage them are hazard-focused and tend to overlook exposure and vulnerability. This leaves potential for Australian FRAs to make better use of a technique [...] Read more.

Floods are the most common and costliest natural disaster in Australia. However, the Flood Risk Assessments (FRAs) employed to manage them are hazard-focused and tend to overlook exposure and vulnerability. This leaves potential for Australian FRAs to make better use of a technique which holistically incorporates all three flood risk components. In this study, flood exposure assessment and mapping for the Hawkesbury-Nepean Catchment (HNC), a flood-prone region in Australia, was conducted. Three flood exposure indicators—population density, land use type, and critical infrastructure density—were selected to derive the flood exposure index (FEI). Results demonstrated that Statistical Areas Level 2 (SA2s) on or near the floodplain, located near the eastern border of the HNC, are severely or extremely flood-exposed due to the significant presence of flood-exposed assets such as hospitals or police stations. The Wahroonga (West)—Waitara SA2 was the most exposed SA2 in the catchment (extreme exposure). This was followed by the Acacia Gardens, Glendenning—Dean Park, and Cambridge Park SA2s (all severely exposed). The Goulburn SA2 was also identified as severely flood-exposed even though it remains outside of the floodplain. This is due to its many exposed assets as Australia’s first inland town. All selected indicators were found to either strongly or moderately positively correlate with the FEI. Ultimately, this novel FEI can assist in the reduction of flood risk in the HNC, as well as foster community resilience strategies. Additionally, the developed scalable and replicable methodology can be applied to other flood-prone regions of Australia. Full article

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16 pages, 7924 KiB

Open AccessArticle

Application of the RAPS Method of Time Series Analysis to the Assessment of Grout Curtain Performance in Karst—A Case Study of the Hydro Energy Power Plant (HEPP) Mostar Dam in Bosnia and Herzegovina

by Bojan Đurin, Mirna Raič and Petra Sušilović

Hydrology 2022, 9(11), 192; https://doi.org/10.3390/hydrology9110192 - 29 Oct 2022

Cited by 5 | Viewed by 1790

Abstract

Concerning the media’s properties, there is always a possibility of changing groundwater flow conditions surrounding hydroelectric power plants. Causes for such events could be natural or anthropogenic, which is, in many cases, not so obvious to determine. In addition, determining a period when [...] Read more.

Concerning the media’s properties, there is always a possibility of changing groundwater flow conditions surrounding hydroelectric power plants. Causes for such events could be natural or anthropogenic, which is, in many cases, not so obvious to determine. In addition, determining a period when changes in the groundwater flow occur is a complex task. All of the above mentioned are of crucial importance due to the operational work of hydropower plants, i.e., the optimization of the inflow and outflow of the water in the turbine, regardless of the hydropower plant type. All types listed require a particular approach for solving such issues. Rescaled Adjusted Partial Sums (RAPS) is an appropriate time-series analysis method. In this specific case, observed fluctuations in the time series of the groundwater levels could lead to conclusions about possible irregularities in the shallow as well as the deep zones of the underground water. The concept was shown in this paper in the example of the hydroelectric power plant Mostar dam in Bosnia and Herzegovina. It should be noted that the defined methodology was a novel procedure for analyzing and determining the pathways of the flow of groundwater in the surrounding hydropower plant dams. In other words, such analysis could be conducted without the need for complex and expensive drilling and geophysical surveys, tracing, and all other methods. Full article

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10 pages, 2628 KiB

Open AccessArticle

Effect of Vertical Variation of Submerged Vegetation Density on the Flow Resistance

by Sadegh Derakhshan, Esmaeil Dodangeh, Hossein Afzalimehr, Mohammad Nazari-Sharabian, Hamidreza Raeisifar and Moses Karakouzian

Hydrology 2022, 9(11), 191; https://doi.org/10.3390/hydrology9110191 - 29 Oct 2022

Viewed by 1329

Abstract

Aquatic vegetation plays a critical role in aquatic environments and provides various valuable services. To characterize vegetation, vegetation density and flexibility are usually used as parameters, but aquatic vegetation found in nature may have a non-uniform distribution of density in the vertical direction. [...] Read more.

Aquatic vegetation plays a critical role in aquatic environments and provides various valuable services. To characterize vegetation, vegetation density and flexibility are usually used as parameters, but aquatic vegetation found in nature may have a non-uniform distribution of density in the vertical direction. Studies have shown that this non-uniformity could impact the flow structure and flow resistance. With the aim of studying the effect of vertical variation of submerged vegetation density on the flow resistance and bulk flow characteristics, the hydrodynamics of three types of wooden model vegetation elements were compared in the laboratory. Vegetation models had the same density but different vertical distributions of density. All other influential parameters were kept constant so that any differences in the flow structure and the flow resistance would be attributable to the distribution of density in the vertical direction. The results show that the vertical distribution of submerged vegetation density impacts the flow field, bed shear stress, and flow resistance. There was a 41% difference in the value of the drag coefficient produced by the models. The distance between the bed and the geometrical center of vegetation elements was introduced as a parameter to quantify the effect of the vertical distribution of vegetation. There is a direct relation between this parameter with both the drag and Manning’s coefficients. The findings of this can study help researchers and practitioners use relevant vegetation parameters. Full article

(This article belongs to the Section Surface Waters and Groundwaters)

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24 pages, 3612 KiB

Open AccessArticle

Experimental Investigation of the Effects of Porosity, Hydraulic Conductivity, Strength, and Flow Rate on Fluid Flow in Weakly Cemented Bio-Treated Sands

by Charalampos Konstantinou and Giovanna Biscontin

Hydrology 2022, 9(11), 190; https://doi.org/10.3390/hydrology9110190 - 28 Oct 2022

Cited by 8 | Viewed by 2108

Abstract

Fluid injection in a porous medium is the underlying mechanism for many applications in the fields of groundwater hydraulics, hydrology and hydrogeology, and geo-environmental engineering and in the oil and gas industry. Fluid flow experiments in porous media with a viscous fluid at [...] Read more.

Fluid injection in a porous medium is the underlying mechanism for many applications in the fields of groundwater hydraulics, hydrology and hydrogeology, and geo-environmental engineering and in the oil and gas industry. Fluid flow experiments in porous media with a viscous fluid at varying injection rates were conducted in a modified Hele-Shaw setup. The granular media were three-dimensional bio-cemented sands of various grain sizes across various cementation levels, generating a matrix of various hydraulic conductivities, porosities, and strengths. The fluid injection experiments showed that a cavity-like fracture developed, which transitioned to crack-like fractures at higher cementation levels (hence, higher strength). As the flow rate increased, less infiltration was evident and higher breakdown pressure was observed, with propagation pressure reducing to zero. It was harder to induce an opening in cemented specimens with higher hydraulic conductivity and a larger pore network despite their lower strength due to excessive infiltration dominance, which inhibited the build-up of pressure required to generate a fracture. The results of this study suggest that, when designing fluid injection programs, the combined effects of hydraulic conductivity and strength need to be carefully considered. Full article

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19 pages, 4185 KiB

Open AccessArticle

Hydropedological Characteristics of the Cathedral Peak Research Catchments

by Rowena Harrison, Johan van Tol and Philippe Amiotte Suchet

Hydrology 2022, 9(11), 189; https://doi.org/10.3390/hydrology9110189 - 25 Oct 2022

Cited by 1 | Viewed by 1760

Abstract

It has long been recognised that the role of soils is critical to the understanding of the way catchments store and release water. This study aimed to gain an understanding of the hydropedological characteristics and flow dynamics of the soils of three mountain [...] Read more.

It has long been recognised that the role of soils is critical to the understanding of the way catchments store and release water. This study aimed to gain an understanding of the hydropedological characteristics and flow dynamics of the soils of three mountain catchment areas. Digital soil maps of the hydropedological characteristics of the catchments were interpreted and a conceptual response of these watersheds to precipitation was formed. This conceptual response was then tested with the use of site-specific precipitation and streamflow data. Furthermore, piezometers were installed in soils classified as the interflow hydropedological soil group as well as the saturated responsive hydropedological soil group and water table depth data for the three catchments were analysed. Climatic data indicated that there is a lag time effect in the quantity of precipitation that falls in the catchment and the corresponding rise in streamflow value. This lag time effect coupled with data obtained from the piezometers show that the various hydropedological soil groups play a pivotal role in the flow dynamics. Of importance is the unique influence of different wetland systems on the streamflow dynamics of the catchments. The drying and wetting cycles of individual wetland systems influenced both the baseflow connectivity and the overland flow during wetter periods. They are the key focus in understanding the connectivity between the hydropedological flow paths and the contribution of soil water to the stream networks of the three catchments. Full article

(This article belongs to the Topic Hydrology and Water Resources in Agriculture and Ecology)

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17 pages, 15965 KiB

Open AccessArticle

On the Benefits of Bias Correction Techniques for Streamflow Simulation in Complex Terrain Catchments: A Case-Study for the Chitral River Basin in Pakistan

by Muhammad Usman, Rodrigo Manzanas, Christopher E. Ndehedehe, Burhan Ahmad, Oluwafemi E. Adeyeri and Cornelius Dudzai

Hydrology 2022, 9(11), 188; https://doi.org/10.3390/hydrology9110188 - 24 Oct 2022

Cited by 1 | Viewed by 2103

Abstract

This work evaluates the suitability of linear scaling (LS) and empirical quantile mapping (EQM) bias correction methods to generate present and future hydrometeorological variables (precipitation, temperature, and streamflow) over the Chitral River Basin, in the Hindukush region of Pakistan. In particular, LS and [...] Read more.

This work evaluates the suitability of linear scaling (LS) and empirical quantile mapping (EQM) bias correction methods to generate present and future hydrometeorological variables (precipitation, temperature, and streamflow) over the Chitral River Basin, in the Hindukush region of Pakistan. In particular, LS and EQM are applied to correct the high-resolution statistically downscaled dataset, NEX-GDDP, which comprises 21 state-of-the-art general circulation models (GCMs) from the coupled model intercomparison project phase 5 (CMIP5). Raw and bias-corrected NEX-GDDP simulations are used to force the (previously calibrated and validated) HBV-light hydrological model to generate long-term (up to 2100) streamflow projections over the catchment. Our results indicate that using the raw NEX-GDDP leads to substantial errors (as compared to observations) in the mean and extreme streamflow regimes. Nevertheless, the application of LS and EQM solves these problems, yielding much more realistic and plausible streamflow projections for the XXI century. Full article

(This article belongs to the Special Issue Stochastic and Deterministic Modelling of Hydrologic Variables)

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20 pages, 4378 KiB

Open AccessEditor’s ChoiceArticle

On the Benefits of Collaboration between Decision Makers and Scientists: The Case of Lake Como

by Luigi Bertoli, Donata Balzarolo and Ezio Todini

Hydrology 2022, 9(11), 187; https://doi.org/10.3390/hydrology9110187 - 23 Oct 2022

Viewed by 2626

Abstract

Rational Water Resources Management requires effective collaboration between decision-makers involved in the operational management of water resources and scientists, who can allow them to operate in an informed manner through forecasting and decision-making tools. In this article, we show the potential benefits resulting [...] Read more.

Rational Water Resources Management requires effective collaboration between decision-makers involved in the operational management of water resources and scientists, who can allow them to operate in an informed manner through forecasting and decision-making tools. In this article, we show the potential benefits resulting from this collaboration through the description of the emblematic case of Lake Como. The article describes the real case of a collaborative experience between decision makers, who made an effort to highlight and clarify the real management problems to scientists, who in turn needed to understand all the facets of the decision-making process prior to formulating the problem in mathematical terms and incorporating the solution into a decision support system. The resulting tool, which makes extensive hidden use of probabilistic forecasts, stochastic optimization, and Bayesian decision techniques, resulted in a user-friendly environment. After six months of testing, the tool proved to be essential for decision-making and has been in use on a daily basis since 1997. Full article

(This article belongs to the Collection Feature Papers of Hydrology)

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Hydrology, Volume 9, Issue 11 (November 2022) – 20 articles

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