Surface Runoff Conditions Research Articles

Urban occupation and surface runoff in cities: a study case in Piracicaba - SP

This study analyzes how uncontrolled human occupation can negatively impact surface runoff conditions in urban environments. For this purpose, the study assesses the correlation between rainfall, Piracicaba River flow and the urban occupation growth regarding the incidence of floods in Piracicaba-SP. To address the research question: Is the increase in flooding caused by the increased population density? The following data was used: flow and precipitation data in the urban perimeter, obtained from the Piracicaba Water and Electricity Department; population and density data from five neighborhoods based on the "Google Earth Pro" software, covering sixteen years of study. The findings indicate that three districts experienced increased flooding, while two other well-established districts did not encounter significant changes in flood frequency.

Analysis of Made Lamongan Residential Drainage System Using SWMM (Storm Water Management Model) and HEC-RAS (Hydraulic Engineering Centre-River Analysis System) Models

Made Lamongan Residential is located in an area that has a flat slope and is flanked by two rivers Kali Mengkuli and Kali Gorok, the problem in the study area is that the drainage system is unable to serve rainwater runoff. This is evidenced by the occurrence of inundation during the rainy season with high intensity. The height of the inundation that occurs in the Residential complex ± 60 cm with a reduction in inundation of more than 12 hours. The calculation results showed that there were several sections of the channel that occurred runoff with a planned Q5 flood discharge of 8.14 m3/sec. Based on the results of surveys in the field, many channels were found that had changed their dimensions due to the renovation of residents' houses. In this study, 1D channel hydraulic modelling was carried out using SWMM and HEC-RAS software to obtain a model that was close to the surface runoff conditions at the study site. The purpose of this study is to obtain the greatest handling of inundation in Made Residential in reducing the height of the inundation based on the model to be carried out, as well as obtaining the value of model calibration at the study site.

Sustainable rural infrastructure: guidelines for roadside slope excavation

The construction of non-engineered, equipment-based rural roads in Nepal Himalaya is one of the predominant causes of landslides. The construction frequency of such roads has significantly increased over the past decade. However, the present guidelines governing slope excavation for these roads are not based on geotechnical characterizations of sites. The current study uses the limit equilibrium method with the Mohr–Coulomb constitutive model to determine safe cut heights and slopes for varying geometric and material parameters. GeoStudio Slope/W was used to model soil slopes with various gradients, and cuts with varying depths and slope angles were modeled to calculate the factor of safety (FoS) against shear failure for different geometric and material conditions. The results of the study were visualized in design charts with FoS as the dependent variable. The analysis highlights the importance of different parameters, i.e., excavation depth, excavation slope, and existing ground slope in the FoS, in addition to the slope-forming material. Furthermore, a field study was carried out to validate the model using the clustering approach. The results from the field are similar to those from the numerical model, although some additional site-specific parameters like vegetation cover and surface runoff conditions should be considered before selecting the cut slope. Finally, this study proposes that future road construction guidelines should consider terrain parameters, hydrology, and geotechnical site conditions to promote sustainable road infrastructure and reduce future disaster risks in the Himalayan region.

The Plastic Pathfinder: A macroplastic transport and fate model for terrestrial environments

Land-based plastic waste is the major source for freshwater and marine plastic pollution. Yet, the transport pathways over land remain highly uncertain. Here, we introduce a new conceptual model to forecast plastic transport on land: the Plastic Pathfinder; a numerical model that simulates the spatiotemporal distribution of macroplastic (>0.5 cm) at a river basin scale. The plastic transport driving forces are wind and surface runoff, while plastic transport is resisted by terrain surface friction. The terrain surface friction, a function of the slope and land use, is converted into thresholds that define the critical wind and surface runoff conditions required to mobilize and transport macroplastic waste. When the wind and/or surface runoff conditions exceed their respective thresholds, the model simulates the transport and (re)distribution of plastics, resulting in plastic accumulation hotspots maps and high probability transport route maps. The Plastic Pathfinder contributes to a better mechanistic understanding of plastic transport through terrestrial environments, and upon future calibration and validation, can serve as a practical tool to optimize plastic waste prevention, mitigation, and reduction strategies.

Mapping Gully Erosion Variability and Susceptibility Using Remote Sensing, Multivariate Statistical Analysis, and Machine Learning in South Mato Grosso, Brazil

In Brazil, the development of gullies constitutes widespread land degradation, especially in the state of South Mato Grosso, where fighting against this degradation has become a priority for policy makers. However, the environmental and anthropogenic factors that promote gully development are multiple, interact, and present a complexity that can vary by locality, making their prediction difficult. In this framework, a database was constructed for the Rio Ivinhema basin in the southern part of the state, including 400 georeferenced gullies and 13 geo-environmental descriptors. Multivariate statistical analysis was performed using principal component analysis (PCA) to identify the processes controlling the variability in gully development. Susceptibility maps were created through four machine learning models: multivariate discriminant analysis (MDA), logistic regression (LR), classification and regression tree (CART), and random forest (RF). The predictive performance of the models was analyzed by five evaluation indices: accuracy (ACC), sensitivity (SST), specificity (SPF), precision (PRC), and Receiver Operating Characteristic curve (ROC curve). The results show the existence of two major processes controlling gully erosion. The first is the surface runoff process, which is related to conditions of slightly higher relief and higher rainfall. The second also reflects high surface runoff conditions, but rather related to high drainage density and downslope, close to the river network. Human activity represented by peri-urban areas, construction of small earthen dams, and extensive rotational farming contribute significantly to gully formation. The four machine learning models yielded fairly similar results and validated susceptibility maps (ROC curve > 0.8). However, we noted a better performance of the random forest (RF) model (86% and 89.8% for training and test, respectively, with an ROC curve value of 0.931). The evaluation of the contribution of the parameters shows that susceptibility to gully erosion is not governed primarily by a single factor, but rather by the interconnection between different factors, mainly elevation, geology, precipitation, and land use.

Determining trigger factors of soil mass failure in a hollow: A study based in the Sichuan Province, China

Soil mass failure disasters are among the most destructive disasters in mountainous areas worldwide, and they continue to receive significant attention in the literature. However, factors that influence soil mass failure in hollows have not been explored via experimental approaches. In this study, we conducted a series of indoor hollow–flume experiments to exhibit how the three factors, namely, initial moisture content, slope angle, and clay content, influence the collapse of soil mass under surface runoff conditions. Our findings revealed that the major processes causing soil mass failure were internal seepage erosion resulting from subsurface runoff, migration of fine particles, development of tension cracks, increase in pore water pressure, and decrease in cohesion. Fluctuations in pore water pressure were characterized by two main trends: (1) an abrupt rise under static liquefaction and (2) a decrease before failure due to dilatancy. The time required for soil mass failure first decreased and then increased with the increase in moisture content. The soil mass with an initial moisture content of ∼12.5% was more critical to the failure. In addition, the time required for soil mass failure decreased with increasing slope angle, revealing a slope angle of 40° to be more prone to failure. The buildup of pore water pressure was found to increase with clay content; soil with a clay content of ∼7.5% required the shortest amount of time to initiate slides. Thus, our results provide a thorough insight into the processes and factors involved in the initiation and development of soil mass failure in hollow areas, which can be used by public agencies to improve monitoring, early warning, and forecasting systems. Notably, our study can help identify risk-prone source areas, and sensors can be installed to monitor potential mass failure locations.

Применение беспилотных летательных аппаратов для геоморфологического картографирования оползневых склонов хребта Аибга (Западный Кавказ)

Aerial sounding of the study area of the northern slope of the Aibga Ridge was carried out using unmanned aerial vehicles (UAVs) for geomorphological large-scale geoinformation mapping of landslide slopes. The site of work was chosen on the basis of the previously carried out ecological and geomorphological zoning of the slopes of the Aibga Ridge (Sochi National Park) and represents the slopes of the Chernaya Piramida mountain covered with forest and alpine meadows. A fragment of the ridge slope in the area of an ancient stabilized seismogenic gravitational landslide was studied. The morphology of the relief was partially changed during the construction of sports facilities—ski slopes and cable cars. The creation of clearings in forests, a partial change in the morphology of the natural relief and surface runoff conditions led to local activation of landslide processes, including on ski slopes and other infrastructure facilities. The newly formed landslide slopes are confined to the junction of natural and man-made relief forms: the ski slopes and the slopes of the hollows of temporary watercourses. As a result of field work using the global navigation satellite system (GNSS), a local reference geodetic network of centimeter accuracy was formed—a planned-altitude substantiation (PVO), which served as a geodetic basis for processing sounding materials and subsequent geoinformation mapping. Aerial sounding was carried out using the DJI Mavic 2 Pro and DJI Mini UAVs, more than 1,000 digital images of the study area in nadir and prospective have been accumulated. In addition, in order to identify the relief forms of the underlying surface on separate fragments of the study area, covered with dense broad-leaved forest (beech, hornbeam), a tacheometric survey was carried out. Field research materials served as the basis for geomorphological mapping of the landslide slopes of the Aibga Ridge and the creation of the corresponding thematic layers in the GIS software environment.

Zmiany warunków hydrologicznych wynikające z tworzenia nasypów – przegląd przypadków

The article discusses typical examples of the impact of embankments on the surrounding water conditions. The studied cases illustrate the two most common groups of changes in hydrological conditions related to the formation of embankments. One such change is the raising of the groundwater table under the embankment, which usually leads to high level of moisture in the immediate vicinity of the embankment. Three cases were discussed in this group. One is a typical impact of a large embankment that has caused a significant increase in soil moisture nearby. The second example is a situation where the terrain lying between the embankments is strongly damp. The third example is a plot of land which, despite its particularly unfavourable location – surrounded on three sides by embankments – has not been damp due to the unusually high permeability of the ground. The second group of changes consists of various modifications of surface runoff conditions. Some embankments – made of impermeable materials – increase surface runoff by blocking the infiltration of rainwater. Other embankments redirect or block surface runoff, causing the formation of landlocked area. In addition, an analysis of one reported case has revealed the effects of backfilling a large gorge, which had significantly increased the surface catchment area, which in turn resulted in a significant increase in surface runoff. The case of building embankments on a river floodplain was also discussed. The article shows that similar nature of changes in topography may cause different hydrological effects depending on the permeability and retention capacity of the ground.

Surface runoff response to long-term land use changes: Spatial rearrangement of runoff-generating areas reveals a shift in flash flood drivers

Nowadays, rapid growths of urban areas and associated land use/land cover (LULC) changes notably affect the surface runoff response to rainfall in urbanised catchments. This effect of urbanisation on surface runoff is frequently addressed since it relates to the increasing incidence of pluvial floods worldwide. Studies on this issue commonly assess runoff changes over several most recent decades. However, human-induced factors likely resulted in increased surface runoff and associated flash floods in rural catchments even in the past centuries. Such long-term changes have been rarely studied and thus are not well documented. This paper aims to fill this gap and assess the surface runoff response to LULC changes in a small catchment in southwestern Slovakia over more than two centuries. To meet this goal, we applied the Soil Conservation Service Curve Number (SCS-CN) method. We mapped past (1784) and present (2018) LULC classes based on historical maps and modern remote sensing data. Then, we estimated surface runoff depths for specific design rainstorms for both periods by executing CN method equations in the ArcGIS environment. Results revealed significant changes in surface runoff conditions between evaluated periods. In total, surface runoff magnitudes increased by ~230 and ~ 130% for 40- and 65-mm design rainstorms, respectively, compared to 1784. Moreover, surface runoff values show different spatial patterns on historical and present-day output raster images revealing spatial redistribution of runoff-enhancing and runoff-preventing areas during the evaluated period. Although both infiltration-enhancing and runoff-enhancing effects of LULC changes were identified, the latter effect associated with urbanised lowland areas was recognised as prevailing at present. In contrast, runoff-promoting conditions were associated with hilly vineyard areas in the past. These findings likely have important implications for understanding the past and present LULC-based controls of surface runoff generation and flash floods initiation.

Methodology of ecological and geological assessment of technogenic oil product deposits (on the example of the territory of the Burnakovsky lowland, Nizhny Novgorod)

The present study is devoted to the assessment of hydrogeological conditions in the field of discharge of the water-bearing horizon. The study is carried out on the territory of the Burnakovo Lowland tank farm, Nizhny Novgorod, and the adjacent areas. These areas are potentially adverse areas with disturbed surface runoff conditions. Within these anthropogenically modified areas of megacities, there is pollution due to additional infiltration nutrition. In this case, it is possible to form a layer of liquid oil products on the surface of the water-bearing horizon and subsequent migration of pollutants within the catchment areas of rivers and water bodies.

Progress in the Remote Sensing Monitoring of the Ecological Environment in Mining Areas.

Based on the results of an extensive literature research, we summarize the research progress of remote sensing monitoring in terms of identifying mining area boundaries and monitoring land use or land cover changes of mining areas. We also analyze the application of remote sensing in monitoring the biodiversity, landscape structure, vegetation change, soil environment, surface runoff conditions, and the atmospheric environment in mining areas and predict the prospects of remote sensing in monitoring the ecological environment in mining areas. Based on the results, the accurate classification of land use or land cover and the accurate extraction of environmental factors are the basis for remote sensing monitoring of the ecological environment in mining areas. In terms of the extraction of ecological factors, vegetation extraction is relatively advanced in contrast to the extraction of animal and microbial data. For the monitoring of environmental conditions of mining areas, sophisticated methods are available to identify pollution levels of vegetation and to accurately monitor soil quality. However, the methods for water and air pollution monitoring in mining areas still need to be improved. These limitations considerably impede the application of remote sensing monitoring in mining areas. The solving of these problems depends on the progress of multi-source remote sensing data and stereoscopic monitoring techniques.

Investigation of the initiation of shallow failure in widely graded loose soil slopes considering interstitial flow and surface runoff

Wide-grade loose soils (WGLS) are common source materials for denuding hillslopes, mobilizing sediments, and causing geo-hazards. Although the effects of interstitial flow process on the shallow failure of WGLS materials are widely studied during rainfall, the combined effects of interstitial flow and surface runoff processes remain poorly understood. This in turn limits our ability to better understand the effects of fluid flow on the mechanical response of hillslope soils. In this study, flume model test was performed under rainfall infiltration and surface runoff conditions to further study the initiation process of WGLS failure. Based on the experimental results, a new mathematical model was then explored by incorporating hydrodynamic theory considering the surface runoff and fine particle migration effect. Experimental results shown that no significant slope failure was triggered only under the rainfall infiltration condition, but the slope materials could transform into continuous surface erosion under the thin surface runoff condition. Meanwhile, the back calculations and analyses of the mathematical model shown that the established model here proved to be better suited for describing WGLS failure.

Magyarország határvízi egyezményei a belvízvédekezés tükrében

Due to the natural conditions and vulnerability to water damages of Hungary, the magnitude of the protection system is unique, which crosses national borders. In order to protect Hungary against water damage, cross-border cooperation is extremely important which is based on the nearly 100-year-old water agreements with our neighbouring countries. In recent years, the countries have made significant interventions on the cross-border river basins changing natural surface runoff conditions. Ensuring water demand to create a good ecological status by WDF (Water-Framework Directive) and also the need to share natural water resources is becoming highly important, especially to mitigate the effects of climate change. This process is reinforced by various international conventions which also has an impact on the current cross-border water agreements.

GIS-based Approach to Estimate Surface Runoff in Small Catchments: A Case Study

AbstractThe issue of surface runoff assessment is one of the important and relevant topics of hydrological as well as geographical research. The aim of the paper is therefore to estimate and assess surface runoff on the example of Vyčoma catchment which is located in the Western Slovakia. For this purpose, SCS runoff curve number method, modeling in GIS and remote sensing were used. An important task was the creation of a digital elevation model (DEM), which enters the surface runoff modeling and affects its accuracy. Great attention was paid to the spatial interpretation of land use categories applying aerial imagery from 2013 and hydrological soil groups as well as calculation of maximum daily rainfall with N-year return periods as partial tasks in estimating surface runoff. From the methodological point of view, the importance of the paper can be seen in the use of a simple GIS-based approach to assess the surface runoff conditions in a small catchment.

Micro-topographical surface alteration caused by tillage and irrigation canal maintenance and its consequences on excess water development

The most common forms of low relief plains created by agriculture are ridges and furrows that develop parallel to ploughing and irrigation or drainage canals. These micro-forms influence the surface run-off conditions of a field, as they act as overland flow paths or barriers depending on their orientation, resulting in the development of excess water. The consequences of excess water retention are soil degradation and crop loss, which for example, in 2011 threatened 11% of the agricultural lands of Hungary. The goals of the present research are to evaluate the spatial distribution and morphology of forms created by tillage and irrigation or drainage canal maintenance, and to study their effect from the point-of-view of blocked drainage and excess water build-up. The studied tillage ridges were formed during the last 20 years and their height reaches 0.19–0.26m. The ridges block the overland flow and facilitate the development of excess water on 14.1% of the study area. Along 85.4% of the canal banks canal berms appear. Their average height is 0.38m (max: 1.43m) and width is 17m (max: 54.8m). Considering the height of the tillage ridges, they have less influence on overland flow than that of the canal berms, but, due to the low relief of the area, both play an important role in disconnecting overland flow routes. Thus (dis)connectivity could develop within an agricultural plot as the higher parts of the plot could be disconnected from the lower parts by ridges, and the canal berms disconnect the plot and the artificial drainage system. Regarding overland flow, ridges and berms disconnect the plots from their drainage canals (buffer function), and in the natural drainage routes they act as barriers. The dis-connectivity function of the studied forms increases over time and as a result of intensive tillage. Therefore, they will play a more and more important role in altering overland flow and developing excess water hazard.

Retrospective Analysis of Recent Flood Events With Persistent High Surface Runoff From Hydrological Modelling

Abstract. Floods are one of the most common and widespread disasters in India, with an estimated 40Mha of land prone to this natural disaster (National Flood Commission, India). Significant loss of property, infrastructure, livestock, public utilities resulting in large economic losses due to floods are recurrent every year in many parts of India. Flood forecasting and early warning is widely recognized and adopted as non-structural measure to lower the damages caused by the flood events. Estimating the rainfall excess that results into excessive river flow is preliminary effort in riverine flood estimation. Flood forecasting models are in general, are event based and do not fully account for successive and persistent excessive surface runoff conditions. Successive high rainfall events result in saturated soil moisture conditions, favourable for high surface runoff conditions. The present study is to explore the usefulness of hydrological model derived surface runoff, running on continuous times-step, to relate to the occurrence of flood inundation due to persistent and successive high surface runoff conditions. Variable Infiltration Capacity (VIC), a macro-scale hydrological model, was used to simulate daily runoff at systematic grid level incorporating daily meteorological data and land cover data. VIC is a physically based, semi-distributed macroscale hydrological model that represents surface and subsurface hydrologic process on spatially distributed grid cell. It explicitly represents sub-grid heterogeneity in land cover classes, taking their phenological changes into account. In this study, the model was setup for entire India using geo-spatial data available from multiple sources (NRSC, NBSS&LUP, NOAA, and IMD) and was calibrated with river discharge data from CWC at selected river basins. Using the grid-wise surface runoff estimates from the model, an algorithm was developed through a set of thresholds of successive high runoff values in order to identify grids/locations with probable flooding conditions. These thresholds were refined through iterative process by comparing with satellite data derived flood maps of 2013 and 2014 monsoon season over India. India encountered many cyclonic flood events during Oct–Dec 2013, among which Phailin, Lehar, and Madi were rated to be very severe cyclonic storm. The path and intensity of these cyclonic events was very well captured by the model and areas were marked with persistent coverage of high runoff risk/flooded area. These thresholds were used to monitor floods in Jammu Kashmir during 4–5 Sep and Odisha during 8–9 Aug, 2014. The analysis indicated the need to vary the thresholds across space considering the terrain and geographical conditions. With respect to this a sub-basin wise study was made based on terrain characteristics (slope, elevation) using Aster DEM. It was found that basins with higher elevation represent higher thresholds as compared to basins with lesser elevation. The results show very promising correlation with the satellite derived flood maps. Further refinement and optimization of thresholds, varying them spatially accounting for topographic/terrain conditions, would lead to estimation of high runoff/flood risk areas for both riverine and drainage congested areas. Use of weather forecast data (NCMWRF, (GEFS/R)), etc. would enhance the scope to develop early warning systems.

WATER QUALITY AT THE BUFFALO NATIONAL RIVER, ARKANSAS, 1991-2001

The Buffalo National River (BNR) is a relatively unpolluted, free-flowing river with riffle-pool geomorphology,located in north-central Arkansas. The specific objectives of this study were to: (1) evaluate differences betweenphysicochemical properties and concentrations in water quality samples representing base flow and surface runoff conditions,(2) determine trends in physicochemical properties and concentrations using three datasets (all data, data representing baseflow conditions, and data representing surface runoff conditions), and (3) compare flow-weighted constituent concentrationsand yields at the BNR to relatively undisturbed catchments and a relatively developed catchment. Water quality trends wereevaluated (. = 0.1) using constituent data from 1991 through 2001 and using subsets of these data representing water qualitysamples collected during either base flow or surface runoff conditions. Trends were assessed by (1) appropriately transformingwater quality data and daily discharge, (2) flow-weighting water quality data using a smoothing technique, and (3) evaluatingresiduals from smoothing versus time for trends. Trend analyses suggested that only nitrogen, sediment, and E. coliconcentrations increased from 1991 through 2001 in the BNR, particularly during surface runoff conditions. Most temporalchanges in constituents occurred during surface runoff conditions, and these changes were not necessarily reflected during baseflow conditions. Flow-weighted nutrient concentrations and yields were greater at the BNR compared to median values forrelatively undeveloped basins across the U.S. Nutrient concentrations and yields at the BNR were only slightly greater than orequal to the values representing the 75th percentile of reference streams. However, nutrient concentrations and yields at the BNRwere less than at relatively developed basins within the same ecoregion. By evaluating base flow and surface runoff water qualitysamples separately for trends, we gained additional insight into the particular flow conditions exhibiting significant trends.Identification of flow conditions associated with trends aids in determining constituent sources and hence appropriateconstituent abatement.

Potential for travertine formation: Fossil Creek, Arizona

Chemical analyses of water emanating from Fossil Springs in Central Arizona were conducted to predict changes in travertine deposition related to changes in stream discharge caused by diversion for hydroelectric power generation. During spring of 1996, water was sampled at 15 locations during normal seepage flow in a 6.7 km reach below Fossil Springs and at full baseflow during turbine maintenance. Analyses resulted in a rate of 11,923 kg d −1 of CaCO 3 precipitated from 1218 l s −1 of water emanating from the springs, while flows of 5.6 l s −1 that seep past a diversion dam produced 46 kg d −1 of CaCO 3 precipitation. Active travertine dams currently occur predominantly below the Irving hydroelectric powerplant with partial return of diverted flow back into the natural channel. The lower reach resulted in 519 kg d −1 of CaCO 3 precipitated from the return of 56.6 l s −1 with a reduced rate of precipitation during surface runoff conditions due to a dilution effect. Artificial substrates were located at sites in the lower reach for comparison with mass transfer rates derived from changes in water chemistry. Comparison between actual precipitation rates and overall mass transfer rates suggested preferential deposition was occurring at dam locations. Rates of mass transfer for high flow were greater than lower flow. Overall, mass transfer rates for the upper reach were proportional to the flow velocities with total mass transfers for both flows being approximately equal.

Variation interannuelle du bilan hydrique du lac Tanganyika (1932–1995): changement dans la relation précipitation-excédent lacustre / Interannual variation of the water budget of Lake Tanganyika (1932–1995): changes in the precipitation-lake water excess relationship

The data collected have allowed the evaluation of the variations in the water levels of Lake Tanganyika between 1932 and 1995, the discharge at the outlet, the excess of the lake budget (or “level without discharge”, ΔH*), and the precipitation on the drainage area. The evolution of the annual lake budget is related to the precipitation variability. However a marked increase in the excess after 1961 is shown, which corresponds to a change in the relationship between annual excess and precipitation, which further corresponds to a higher effectiveness of rainfall. This marked change in the lake water budget could partly correspond to wetter conditions at the beginning of the rainy season, but the man-induced changes in land use and in the surface runoff conditions appear partly responsible for the difference in the lake sensitivity to precipitation.