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Showing papers on "River engineering published in 2019"


Journal ArticleDOI
01 Mar 2019-Catena
TL;DR: In this article, a hybrid intelligence approach based on evolutionary fuzzy approach is developed to predict river suspended sediment concentration (SSC) using discharge information as it is the main trigger for the SSC amount.
Abstract: Providing a robust and reliable prediction model for suspended sediment concentration (SSC) is an essential task for several environmental and geomorphology prospective including water quality, river bed engineering sustainability, and aquatic habitats. In this research, a novel hybrid intelligence approach based on evolutionary fuzzy (EF) approach is developed to predict river suspended sediment concentration. To demonstrate the modeling application, one of the highly affected rivers located in the north-western part of California is selected as a case study (i.e., Eel River). Eel River is considered as one of the most polluted river due to the streamside land sliding, owing to the highly stochastic water river discharge. Thus, the predictive model is constructed using discharge information as it is the main trigger for the SSC amount. The prediction conducted on different locations of the stream (i.e., up-stream and down-stream stations). Three different well-established integrative fuzzy models are developed for the validation purpose including adaptive neuro-fuzzy inference system coupled with subtractive clustering (ANFIS-SC), grid partition (ANFIS-GP), and fuzzy c-means (ANFIS-FCM) models. The predictive models evaluated based on several numerical indicators and two-dimension graphical diagram (i.e., Taylor diagram) that vividly exhibits the observed and predicted values. The attained results evidenced the predictability of the EF model for the SSC over the other models. The discharge information provided an excellent input attributes for the predictive models. In summary, the discovered model showed an outstanding data-intelligence model for the environmental perspective and particularly for Eel River. The methodology is highly qualified to be implemented as a real-time prediction model that can provide a brilliant approach for the river engineering sustainability.

80 citations


Journal ArticleDOI
TL;DR: In this article, the authors present three specific examples of highly relevant issues for the future river basin management of the Danube: (a) long-term impacts in the catchment such as changes in flood patterns and potential ecological consequences; (b) complex feedback loops linking the spread of neozoa with intertwined stressor responses due to river engineering for different purposes; and (c) linkages between different assessment approaches based on European legal frameworks to analyse the specific pressures at different spatial scales.
Abstract: For centuries, rivers have experienced massive changes of their hydromorphic structures due to human activities. The Danube River, the second largest river in Europe, is a case in point for long‐term societal imprint. Resulting human‐induced pressures are a key issue for river management, aiming to improve the ecological conditions and guarantee the provision of ecosystem services. As the most international river basin in the world, the management of the Danube is particularly challenging and needs a well‐organized cooperation of 19 nations. The recent river basin management plan has identified pollution and hydromorphological alterations as most pressing problems, but it has also acknowledged newly emerging issues. In this article, we present 3 specific examples of highly relevant issues for the future river basin management of the Danube: (a) long‐term impacts in the catchment such as changes in flood patterns and potential ecological consequences; (b) complex feedback loops linking the spread of neozoa with intertwined stressor responses due to river engineering for different purposes; and (c) linkages between different assessment approaches based on European legal frameworks to analyse the specific pressures at different spatial scales. These examples highlight the need for a more integrated approach in future Danube River Basin management schemes. Furthermore, large‐scale effects such as climate change and interactions of multiple pressures need to be addressed in future management to increase resilience of the river system and to allow a sustainable ecosystem‐based management of rivers.

38 citations


Journal ArticleDOI
TL;DR: In this article, the authors explored the feasibility of newly intelligent model called Radial basis M5 model tree (RM5Tree) for suspended sediment load (St) prediction for daily scale information at Trenton hydrological station, Delaware River.
Abstract: Accurate suspended sediment transport prediction is highly significant for multiple river engineering sustainability. Conceptually evidenced, sediment load transport is highly stochastic, spatial distributed and redundant pattern due to the incorporation of various hydrological and morphological variables such as river flow discharge and sediment physical properties. The motivation of this study is to explore the feasibility of newly intelligent model called Radial basis M5 model tree (RM5Tree) for suspended sediment load (St) prediction for daily scale information at Trenton hydrological station, Delaware River. Numerous input combination attributes are formulated based on the preceding information of sediment and river flow discharge. The prediction accuracy “based statistical and graphical visualizations” of the proposed model validated against numerous well-established predictive models including response surface method (RSM), artificial neural network (ANN) and classical M5Tree based models. The investigated input combinations behaved differently from one case to another. The optimum input combination attributes are included two months lead times of sediment and discharge information to predict one step ahead St. The attained results of the proposed RM5Tree model exhibited a remarkable prediction accuracy with minimal values of root mean square error (RMSE≈2091 ton/day) and coefficient of determination (R2≈0.86). This presenting a percentage of enhancement in the prediction accuracies by (51.6, 53.1 and 26.3) over (RSM, ANN and M5Tree) optimal models over the testing phase.

32 citations


Journal ArticleDOI
TL;DR: Replacing riprap sections with near-natural gravel bars and re-connecting former side arms can be recommended as appropriate measures to support the rheophilic fish guild, whereas groyne adaptations appear to be of limited value.

21 citations


Journal ArticleDOI
TL;DR: Hou et al. as mentioned in this paper combined detailed mapping of 1.4 million river reaches across the Australian continent with inundation frequency mapping from 27 years of Landsat data to estimate the average flow width at different recurrence and ephemeral frequency.
Abstract: . Hydromorphological attributes such as flow width, water extent, and gradient play an important role in river hydrological, biogeochemical, and ecological processes and can help to predict river conveyance capacity, discharge, and flow routing. While there are some river width datasets at global or regional scales, they do not consider temporal variation in river width and do not cover all Australian rivers. We combined detailed mapping of 1.4 million river reaches across the Australian continent with inundation frequency mapping from 27 years of Landsat observations. From these, the average flow width at different recurrence frequencies was calculated for all reaches, having a combined length of 3.3 million km. A parameter γ was proposed to describe the shape of the frequency–width relationship and can be used to classify reaches by the degree to which flow regime tends towards permanent, frequent, intermittent, or ephemeral. Conventional scaling rules relating river width to gradient and contributing catchment area and discharge were investigated, demonstrating that such rules capture relatively little of the real-world variability. Uncertainties mainly occur in multi-channel reaches and reaches with unconnected water bodies. The calculated reach attributes are easily combined with the river vector data in a GIS, which should be useful for research and practical applications such as water resource management, aquatic habitat enhancement, and river engineering and management. The dataset is available at https://doi.org/10.25914/5c637a7449353 (Hou et al., 2019).

20 citations


Journal ArticleDOI
TL;DR: In this article, the problem of countermeasure the local scour effect on bridge piers has been explained and a series of scale models will be developed in the future as per the geometric characteristic of CFD models.

15 citations


Journal ArticleDOI
TL;DR: In this paper, the contribution of bedload flux to the total sediment load exported from tropical sand-bed rivers was measured at the lower Gilgel Abay River in the Blue Nile catchment of Ethiopia catchment area.

14 citations


Journal ArticleDOI
12 Sep 2019-Water
TL;DR: In this article, hydraulic laboratory experiments were conducted in a prismatic rectangular flume using scale-down bridge pier models to understand near bed turbulence characteristics and resulting sediment transport around a pier, and the results showed that the mean flow variable is not enough to explain complex turbulent flow field around the pier leading to the maximum scour.
Abstract: Bridge pier scour is one of the main causes of bridge failure and a major factor that contributes to the total construction and maintenance costs of bridge. Recently, because of unexpected high water during extreme hydrologic events, the resilience and security of hydraulic infrastructure with respect to the scour protection measure along a river reach has become a more immediate topic for river engineering society. Although numerous studies have been conducted to suggest pier scour estimation formulas, understanding of turbulence characteristics which is dominant driver of sediment transport around a pier foundation is still questionable. Thus, to understand near bed turbulence characteristics and resulting sediment transport around a pier, hydraulic laboratory experiments were conducted in a prismatic rectangular flume using scale-down bridge pier models. Three-dimensional velocities and turbulent intensities before and after scour were measured with Acoustic Doppler Velocimeter (ADV), and the results were compared/analyzed using the best available tools and current knowledge gained from recent studies. The results show that the mean flow variable is not enough to explain complex turbulent flow field around the pier leading to the maximum scour because of unsteady flows. Furthermore, results of quadrant analysis of velocity measurements just upstream of the pier in the horseshoe vortex region show significant differences before and after scour.

14 citations


Journal ArticleDOI
TL;DR: In this paper, a river restoration refers to the environmental and ecological aspect of river engineering and aims to improve the natural habitat of a river system using eco-friendly methods, which is referred to as river restoration.
Abstract: River restoration refers to the environmental and ecological aspect of river engineering and aims to improve the natural habitat of a river system using eco-friendly methods. This paper int...

13 citations


Journal ArticleDOI
TL;DR: In this article, the authors analyzed the geomorphic evidence for the potential effects of flow regulation by two dams constituting the Cushman Hydroelectric Project, which began regulating flow in the river's North Fork in 1925 and diverting water out of the basin in 1930.

13 citations


Journal ArticleDOI
14 Mar 2019
TL;DR: In this paper, the influence of non-uniform flow in coarse-bed streams with a submerged vegetation strip on flow characteristics was analyzed using data collected from experiments in a laboratory flume.
Abstract: To better understand the influence of non-uniform flow in coarse-bed streams with a submerged vegetation strip on flow characteristics, data were collected from experiments in a laboratory flume an...

Journal ArticleDOI
TL;DR: In this article, a shallow mixing layer model and modified equations are combined to quantify evolving area along the vegetation patch in a gravel-bed river in the central Iran, and the results reveal that the flow structure in evolving flow (non-developed flow) along the patch resembles that in shallow layer.
Abstract: Investigation of the interactions between submerged vegetation patch and flow structure is of crucial importance for river engineering. Most of hydraulic models have been presented for fully developed flows over uniform vegetation in the laboratory conditions; however, the mentioned interactions are complex in river flows where the flow is not developed along small patch. This reveals a gap between developed and non-developed flow along the vegetation patch. This study was conducted in a gravel-bed river in the central Iran. The results reveal that the flow structure in evolving flow (non-developed flow) along the patch resembles that in shallow mixing layer. Accordingly, a shallow mixing layer model and modified equations are combined to quantify evolving area along the patch. The evolving shallow mixing layer equations for the flow along a non-uniform vegetation patch reach a reasonable agreement with field data. However, the spreading coefficient of this model less than one was reported in literature, 0.06 and 0.12. In addition, the flow immediately downstream the vegetation patch behaves similar to a jet and is parameterized by two conventional models, conventional logarithmic law and mixing layer theory. These models present a reasonable agreement with the measured velocity profiles immediately downstream the patch.

Journal ArticleDOI
05 Jun 2019-Water
TL;DR: In this article, the authors examined decadal-scale geomorphic responses in a low-lying large river system subject to different human interventions, as well as natural flood events, and found that the change pattern of thalweg profiles appear to be controlled by backwater effects.
Abstract: The lowermost Mississippi River (LMR) is one of the largest deltaic systems in North America and one of the heavily human-manipulated fluvial river systems. Historic hydrographic surveys from the mid-1900s to the early 2010s were used to document the thalweg morphology adjustments, as well as the riffle–pool sequences. Extensive aggradation was observed during 1950s to 1960s, as the Atchafalaya River was enlarging before the completion of the Old River Control Structure (ORCS). Following the completion of the ORCS, reductions in sediment input to the LMR resulted in net degradation of the thalweg profile patterns since the mid-1960s except for the 1992–2004 period. Different flood events that supplied sediment might be the cause of upstream aggradation from 1963–1975 and net aggradation along the entire reach from 1992–2004. Furthermore, the change pattern of thalweg profiles appear to be controlled by backwater effects, as well as the Bonnet Carre spillway opening. Results from riffle–pool sequences reveal that the averaging Ws ratios (length to channel width) are 6–7, similar to numerous previous studies. Temporal variations of the same riffles and pools reveal that aggradation and degradation might be heavily controlled by similar factors to the thalweg variations (i.e., sediment supply, backwater effects). In sum, this study examines decadal-scale geomorphic responses in a low-lying large river system subject to different human interventions, as well as natural flood events. Future management strategies of this and similar river systems should consider recent riverbed changes in dredging, sediment management, and river engineering.

Journal ArticleDOI
01 Feb 2019-Water
TL;DR: In this paper, the authors compared the situation of bed load transport in the Lososina River before and after engineering training works showing how much sediment is transported downstream along the river channel to the Czchow artificial lake.
Abstract: The prediction and calculation of the volume of gravel and/or sand transported down streams and rivers—called bed-load transport is one of the most difficult things for river engineers and designers because, in addition to field measurements, personnel involved in such activities need to be highly experienced. Bed-load transport treated by many engineers marginally or omitted and often receives only minor consideration from engineers or may be entirely disregarded simply because they do not know how to address the issue—in many cases, this is a fundamental problem in river management tasks such as: flood protection works; river bank protection works against erosion; building bridges and culverts; building water reservoirs and dams; checking dams and any other hydraulic structures. Thus, to share our experience in our paper, bed-load transport was calculated in two river/stream mountain catchments, which are different in terms of the characteristics of the catchment area and the level of river engineering works performed along the stream channel—both are tributaries of the Dunajec River and have similar Carpathian flysh geology. The studies were performed in the Mlyne stream and in the Lososina River in Polish Carpathians. Mlynne is one of the streams in the Gorce Mountains—it is prone to flash flooding events and has caused many problems with floods in the past. It flows partially in the natural river channel and partially in a trained river channel lined with concrete revetments. The stream bed load is accumulated in the reservoir upstream of the check dam. The Lososina River is one of the Polish Carpathian mountainous streams which crosses the south of the Beskid Wyspowy Mountains. It mostly has a gravel bed and it is flashy and experiences frequent flooding spring. At the mouth of the Lososina River, there is one of the largest Polish Carpathian artificial lakes—the Czchow lake. The Lososina mostly transports gravel as the bed load to the Czchow water reservoir where the sediment is deposited. In the early seventies, the Lososina was partly canalised, especially in places where passes inhabited areas. The paper compares the situation of bed-load transport in the Lososina River before and after engineering training works showing how much sediment is transported downstream along the river channel to the Czchow artificial lake. Also compared is the Mlynne bed load transport upstream and downstream from the check dam showing how much sediment might be transported and deposited in the reservoir upstream from the check dam and when one could expect this reservoir to be clogged.

Book ChapterDOI
16 Jul 2019
TL;DR: In this paper, a back propagation-based multilayer neural network (BP-MLNN) was proposed to predict the cross-sectional dimensions of stable alluvial channels as simple and robust design tools.
Abstract: Modelling stable alluvial river profile is one of the most important and challenging issues in river engineering that several studies have been dedicated to it. The main objective of this study is to evaluate the back propagation-based multilayer neural network (BP-MLNN) performance in predicting stable alluvial river profile. We used eighty-five observational datasets to train and test, three separate models to predict each of the channel width (w), flow depth (h) and longitudinal slope (s) of stable channels. The network input parameters are the flow discharge (Q), mean sediment size (d50) and affecting Shields parameter (τ*) and w, h and s parameters are the output. It is concluded from the results that the proposed models to predict the width, depth, and slope of stable channels, with a correlation coefficient (R) of 0.96, 0.886, and 0.870 respectively, perform well. The mean absolute relative error (MARE) value of 0.063 related to the width estimation model in comparison with the depth and slope estimation model with MARE value of 0.077 and 0.518 shows the superior accuracy of the BP-MLNN model. The presented BP-MLNN models in this study are therefore recommended in river engineering projects to estimate the cross-sectional dimensions of stable alluvial channels as simple and robust design tools.

Journal ArticleDOI
TL;DR: In this article, numerical simulations using the shallow water model on an unstructured triangular mesh system were conducted to elucidate the hydraulic functions of the Nihon levee system, which was built in the seventeenth century to protect the city of Edo (present-day Tokyo) against flooding.
Abstract: Numerical simulations using the shallow water model on an unstructured triangular mesh system were conducted to elucidate the hydraulic functions of the Nihon levee system, which was built in the seventeenth century to protect the city of Edo (present-day Tokyo) against flooding. Because numerical data related to the topography and hydrology of that era do not exist, simulation conditions were inferred from records from the beginning of twentieth century and recent GIS elevation data and flood records. In the simulation results, floodwaters spread over the floodplain surrounded by the levee system, and the inundation areas expanded gradually through a canal to rice paddies in the adjacent river basin. Furthermore, the rise in the water level induced by the levee system produced a steeper water surface slope in the downstream channel, causing a high-rate discharge to Tokyo Bay, where the water level was practically constant. These results suggest that the river engineering of Japan in the seventeenth century was based on a levee design technique with the aim not of restraining floodwaters with levees but of generating water head differences to divert flood flow from urban areas.

Journal ArticleDOI
TL;DR: In this paper, a public policy model to anticipate floods in Ternate City due to changes in the geo-environmental conditions of the Tugurara River based on geological analysis results is presented.
Abstract: This research was conducted to produce a public policy model to anticipate floods in Ternate City due to changes in the geo-environmental conditions of the Tugurara River based on geological analysis results. These model intended to help the local government in determining the policy to deal with the Tugurara River disaster threat. Analysis of geo-environmental conditions was conducted using statistical methods obtained from previous studies - furthermore, the theory of public policy analysis in determining the appropriate policy for handling the risk that will occur. Results revealed that runoff water correlates with extensive changes of the Tugurara River area. These area change becomes more because of runoff water discharge amount erode the rock on the river wall and cause the river wall as well as the presenting any material river wall along the river as a catastrophic outburst flood lava on a residential area three villages in 2011 (this condition is particular compare than another river in North Maluku or others). Therefore changes Tugurara River area, occurred very significant. The river engineering can refer to the flood prevention model that has been applied to the Jeneberang River in South Sulawesi by building Sabo Dam along the river, adapted to the particular characteristics of the Tugurara River. Therefore, the critical formulation of public policy alternative carried out by the Ternate City government is infrastructure development, community involvement, and networking development. After the public policy is determined, then further research can be conduct on the evaluation and comprehensive analysis of policy implementation.

Journal ArticleDOI
TL;DR: A brief history of the systematic urban river management in ancient Korea can be found in this article, where the authors investigated the evolution of man-made urban stream, Cheonggyecheon the center of old downtown Seoul, Korea was reviewed.

Journal ArticleDOI
TL;DR: In this article, the bed and bank scouring in rivers was identified as one of the major environmental problems for river engineering, hydraulic structures and aquatic environment, and six typologies were proposed to prevent this problem.
Abstract: One of the major environmental problems for river engineering, hydraulic structures and aquatic environment is the bed and bank scouring in rivers. In order to prevent this problem, six typ...

Journal ArticleDOI
TL;DR: In this article, a pilot study was carried out for the slope design of rivers which took into consideration both slope stability and frog ecology, and the results showed that the climbing abilities of frogs on cobblestone are much better than on other materials.
Abstract: A pilot study was carried out for the slope design of rivers which took into consideration both slope stability and frog ecology. Ecological engineering is defined as the design of sustainable ecosystems for the integration of human society with its natural environment for the benefit of both. In river engineering projects, the retaining banks and the river bottom are usually constructed of concrete. Although strong, there are no river-like crevices in these structures that can provide habitats, thus organisms are more vulnerable to predation by natural enemies. Ecological river engineering follows the laws of nature and takes into consideration river diversity and sustainable development. It also takes into consideration ecological and safety factors to create river ecosystems and habitats that are diverse, with a reduced impact on the natural environment. So far, there have been no related cross-subject studies on both the needs of amphibians and the slope stability of river banks. In this study, we attempt to increase our understanding and offer insights into current practices in ecological river slope engineering. The research purposes of this study were to examine (1) the climbing abilities of frogs on various degrees of slope and materials and (2) the failure mechanism of the selected slopes using the finite element method (FEM); and carry out (3) safety analysis using the FEM for the selected slopes, and (4) correlation analysis between the climbing abilities of frogs and the safety factors of slopes. The results show that the climbing abilities of frogs on cobblestone are much better than on other materials. Therefore, when considering the survival needs of frogs, the use of rocky revetment should be encouraged for use on ecological slopes. Our results should enhance knowledge relevant to ecologists and engineers for the creation of safe river slopes that also meet the ecological needs of amphibians.

Journal ArticleDOI
01 Jan 2019
TL;DR: In this paper, the authors deal with the problem of mountain stream gravel mining in the Polish Carpathians and show examples of such bad practices in a very large scale and show that it makes a big problem for river managers.
Abstract: Mountain stream gravel is very often legally and illegally mined and gravel is removed from river beds sometimes on the very large scale which is disastrous for fluvial situation of rivers, for river ecology and river engineering works done for flood protection such as river revetments, bridges and all hydraulic structures. This situation makes a big problem for all river managers. Thus gravel mining of the mountain streams in the Polish Carpathians is the subject of many scientific studies when we observe river problems, but also it has a place in Slovakia. This paper deals with such problems additionally showing examples of such bad practices.

DissertationDOI
01 Jan 2019
TL;DR: In this paper, the authors examine the uprooting process of both pioneer seedlings and established vegetation driven by flow and bed erosion, whose role is to reduce root anchorage, at various spatial scales ranging from a single plant to a river reach.
Abstract: In the last decades, the presence of riparian vegetation on riverbanks and floodplains along rivers was acknowledged not only to improve water quality and heal biological diversity but also to contribute to river evolution processes. When water flow runs over vegetated areas, averaged velocity profile is affected by the presence of stem, branches and leaves, sediment transport changes according to modified turbulence and bed shear stresses and soil shear strength is altered by root binding. As a result, bed scour, bank erosion and accretion, bar migration and width adjustment processes lead to different river morphology evolution. Conversely, flow and sedimentary patterns influence vegetation dynamics, by shaping barebed deposits available for colonisation and by affecting mortality rate, through burying and uprooting processes. This PhD work examines the uprooting process of both pioneer seedlings and established vegetation driven by flow and bed erosion, whose role is to reduce root anchorage, at various spatial scales ranging from a single plant to a river reach. The main purpose of this research is to illustrate the links between temporal scales regarding the hydro-morphological evolution of fluvial systems, such as bed scour development, flood duration and return period, and those proper of biological components with regards to both growth and decay rates of riparian vegetation. The results of this PhD research show the existence of cross-related temporal scales between riparian vegetation and river morphodynamics and demonstrate their relationships with flood return period and event duration. As a final result, this research hints the capability for river to select species and cover according to hydrological regime and biological properties. This is crucial in fluvial environments altered by climate change, where alien species may replace native ones. It also underlines the importance of taking into account riparian vegetation dynamics, effects and interactions to guarantee the reliability of long-term river morphodynamics modelling and the success of river maintenance and restoration strategies.

Book ChapterDOI
21 Aug 2019
TL;DR: In this paper, the presence of riparian vegetation along a riparian zone added the complexity of geomorphological process and increased the Manning's n in left flood-plain, while erosion decreased about 31% as the floodplain was roughened by vegetation.
Abstract: Meander dynamics has been the focus of river engineering for decades; however, it remains a challenge for researchers to precisely visualise natural evolution processes especially in alluvial plains. The evolution of meandering channels is a complex geomorphological process driven by the interactions between flow and alluvial channel beds and banks. The presence of vegetation along a riparian zone added the complexity of geomorphological process. Riparian vegetation is a major roughness element that influences channel morphology, decreases the average flow velocity and physically traps material that transported in alluvial rivers. A laboratory experimental investigation was carried out in Universiti Teknologi Malaysia in order to understand the flow behaviour and morphodynamics for a riparian vegetated flooded meandering channel. The morphological patterns visualisation and river channel profile changes estimation for pre and post flooding were obtained using digital close range photogrammetry technique. The findings prevailed that riparian vegetation had induced higher resistance to the flow and forced the flow to take place in main channel and right flood-plain while reduced the left floodplain flow velocity. The presence of riparian vegetation combined with the river bed morphology had increased the Manning’s n in left flood-plain. The influence of riparian vegetation on the sediment movement in the compound meandering channel was also identified. The sedimentation was 45% increased, while erosion decreased about 31% as the floodplain was roughened by vegetation.

24 May 2019
TL;DR: In this paper, the authors combined numerical methods combined with historical data allow the detailed and quantitative investigation of past weather events such as the 1868 flood, which led to enormous damage in Ticino, Grisons and Valais.
Abstract: Numerical methods combined with historical data allow the detailed and quantitative investigation of past weather events such as the 1868 flood. This flood affected Ticino, Grisons and Valais and led to enormous damage. Based on reanalyses and dynamical downscaling, the event can today be reproduced with hydrological-hydraulic models and the historical damage data can be compared with contemporary flood impacts of a similar magnitude. It can be used as one basis for estimating extreme meteorological and hydrological scenarios for hazard assessment. Moreover, it can help quantifying the effects of the river correction and flood protection measures constructed in the aftermath of the flood. Although the floodplains are now much more intensively populated than at that time, the river engineering measures of the Ticino River in the Magadino plain prove to be effective. We can also learn from a historical analysis for the coping strategies. The event strengthened upcoming positions in flood hazard management and set a new course for the practice of flood management in the long term.

Journal ArticleDOI
TL;DR: In this article, the authors focused on the habitat of river snail (Semisulcospira libertina) and investigated the relationship between habitat of snail and civil parameters by the means of statistical methods.
Abstract: National Monitoring of Biological Indices in Rivers has been conducted in Japan. The data of biology and other indices have been accumulated in qualitative form. In recent years, since river engineering works in consideration of the biological environment are required, utilization of the survey data is expected. In this study, river snail (Semisulcospira libertina) was focused as a biological index. Civil parameters such as river width, depth, and flow velocity, temperature, turbidity, and bed material are mainly used for analysis on rivers selected from all of Mie Prefecture. Area properties and temporal properties on snails were obtained by analyzing data set using both quantification theory and Borda count. Properties of habitat were investigated on Oomatagawa River in the south of Mie Pref. by using self-organizing map (SOM). The relationship between habitat of snail and civil parameters was investigated by the means of statistical methods. River width, bed material, and turbidity made a large contribution to the habitat of time series properties. These three parameters were also important for the habitat of local area properties. Because there is a less organic matter of river water as feed-in Higashi-Kisyu, periphyton on gravel surface could largely contribute to the habitat of snails. The possibility of habitat for river snail was showed on a SOM. It was possible to distinguish between easy habitat and a difficult one to live.

Journal ArticleDOI
TL;DR: In this paper, a segment of the Zohreh River between Sardasht Zeydun bridge and Mohseniyeh village in which has good potential for gravel mining was selected and evaluated for river characteristics, mining potential and application of river matrix method.
Abstract: The materials mining from rivers have a variety of negative and positive effects. Currently, one of the most important issues in river engineering is the proper management of materials mining. In this research, global experiences and international standards for managing sand and gravel mining have been applied to evaluate the mining area in the Zohreh River in Khuzestan province (Iran). One of the evaluation methods in this field is the river matrix method. In this method, which is defined on the basis of river pattern, river characteristics such as river size, site location of materials, associated channel and type of deposit are being considered. In this research, a segment of the Zohreh River between Sardasht Zeydun bridge and Mohseniyeh village in which has good potential for gravel mining was selected and evaluated for river characteristics, mining potential and application of river matrix method. The study indicates that the Zohreh River has a braided pattern in the range. The volume of sediment materials in the target area is about 10 000 m³, the length and width of the mining area are 125 and 80 m respectively, and surface extraction with a maximum depth of 1 m was recommended for extraction of materials. At the end of the research, management solutions and solutions for mining of river materials were presented using various standards.