Flood Levels Research Articles

Mortality rate and life expectancy in Africa: the role of flood occurrence

PurposeThe purpose of this paper is to investigate the effect of flood occurrence on mortality rate and life expectancy amongst 53 African countries.Design/methodology/approachThe study utilizes panel data from the period 2000–2018 on 53 African countries and system generalized method of moments (system GMM) for the analysis.FindingsThe result indicates that flood occurrence causes the destruction of health facilities and the spread of diseases which reduces life expectancy. In addition, flood occurrence increases mortality rate amongst 53 African countries.Research limitations/implicationsPractical implicationsThe study recommends that governments amongst African countries should implement strategies being enshrined in Conference of Parties (COP, 2021) on climate change. This will help to reduce the level of climate change and flood occurrence.Originality/valuePrevious studies focussed on the adverse effect of flood occurrence without considering the issue of life expectancy amongst African countries. This study contributes to existing empirical studies by examining the effect of flood occurrence on mortality rate and life expectancy amongst African countries.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-07-2022-0508.

Effect of depth of flooding on growth and fecundity of fall panicum (Panicum dichotomiflorum)

AbstractFall panicum is the most prevalent and problematic weed in rice in Florida. Outdoor studies were conducted in 2021 to determine the effect of flooding on fall panicum growth and its ability to produce and develop panicles. Fall panicum at the two- to four-leaf and four- to six-leaf stages of development were flooded in stock tanks maintained at flooding depths of 0, 10, 15, 20, and 30 cm for 56 d. Plant height, number of tillers and leaves, leaf area, shoot biomass, root biomass, and panicle branches for both fall panicum leaf stages of development decreased with increasing flooding depth. Fall panicum flooded at the two- to four-leaf stage survived flood depth of 15 cm, whereas plants flooded at the four- to six-leaf stage survived and emerged from a flood depth of up to 20 cm. The 10-cm flood depth resulted in the tallest plants with more leaves, tillers, and leaf area for both growth stages. The probability of fall panicum survival and ability to produce panicles decreased as flood depth increased. Flood depth required for 50% survival for four- to six-leaf-stage plants was estimated to occur at 14 cm, whereas that for plants at the two- to four-leaf stage occurred at 12 cm. The flood depth required to reduce panicle branch production by 50% was estimated to be 15 and 20 cm for two- to four-leaf, and four- to six-leaf-stage plants, respectively. These results show that flooding >10 cm is required to significantly reduce fall panicum survival and ability to produce panicles. Since flood level in rice is usually maintained at an average of 10 cm, chemical weed control will be important to supplement flooding for effective control of fall panicum in rice.

Flood Protection Reliability: The Impact of Uncertainty and Nonstationarity

AbstractRecent catastrophic flood events, increasing flood losses, and climate change challenge current reliability estimates defined by the probability that flood levels will not exceed protection measures over a planning horizon. These estimates depict an expected reliability that mask uncertainty in streamflow and the capacity of river channels and floodplains. We described reliability as a random variable whose distribution depends on uncertainty and nonstationarity in annual maximum flood (AMF) distributions and flow capacity uncertainty. Numerical experiments quantified the impacts of nonstationarity and variance in AMFs and flow capacity uncertainty on estimates of flood protection reliability, thereby providing the first examination of their interacting effects. The distribution of reliability along a regulatory floodplain boundary was quantified through a bootstrap scheme that accounts for nonstationarity and uncertainty in AMFs and flow capacity uncertainty. Results indicated that accounting for uncertainty in flow capacity substantially reduces reliability compared to estimates based solely on flood likelihood; the divergence is greater in the presence of nonstationary AMFs. The distribution of reliability along the regulatory floodplain boundary was spatially heterogeneous due to within‐reach variation in flow capacity uncertainty. Quantifying the distribution of reliability for flood protection measures enables transparent communication and selection of a desired confidence level that is commensurate with a contextually appropriate risk tolerance. Similarly, we show that a desired level of confidence in reliability can be specified to estimate a design flood protection level. These results reveal how the combined impacts of uncertainty and nonstationarity can impact reliability estimates and confidence in those estimates.

Forecasting annual maximum water level for the Negro River at Manaus using dynamical seasonal predictions

Early and skilful prediction of the Negro River maximum water levels at Manaus is critical for effective mitigation measures to safeguard lives and livelihoods. Using dynamical seasonal prediction hindcasts, from six prediction centres, we investigate extending the lead time of previously developed statistical models, which issue forecasts in March for Manaus. The original statistical forecast models used observed rainfall as the major predictor. We advance the capability to issue skilful forecasts earlier, in February. We develop ensemble forecasts by combining predictor data from observations and seasonal hindcasts. We compare those forecasts against the original statistical forecast models and forecasts using the observed climatology or persistence of predictors. The ensemble-mean forecasts, issued in February, using European Centre for Medium-Range Weather Forecasts (ECMWF) hindcast input, perform similarly as the original forecasts issued in March and gain one month of lead time. The ECMWF-based ensemble forecasts skilfully predict the likelihood of water levels exceeding the severe flood level of 29 m. Forecast performance reduces and ensemble spread increases with increasing lead time from February to January. We conclude that forecasts for Manaus maximum water levels can be produced using combined input from observations and real-time ECMWF forecasts.

Fishermen's Livelihood Adaptation in Response to Climate Change: An Empirical Study on South-Western Coastal Zone of Bangladesh

This study aimed to understand the livelihood status of the fishery-dependent communities in the South- Western coast of Bangladesh and their livelihood adaptation in response to climate change. The study was carried out in two villages of Dacope upazila in Khulna District. Data were collected from a purposively drawn sample of 60 fisher’s households through household interviews, key informants’ interviews, and transect walk as well as from secondary sources. The adverse climatic variability influences all the livelihood capitals and strategies of fishing communities. Most households have lower access to sanitation, market transportation, health facilities, GO, and NGO services during the adverse climatic situation. Increased levels of cyclones and floods result in greater damage to fishing equipment, livelihood assets, and lower level of fish catch. Income generation from fisheries-related activities is reducing gradually which affects the livelihoods of the fishers. The study has identified four different practices of adaptation to climate change by those fishing communities where about 71.67% adopted livelihood diversification. To cope with the changing climate and variability most of the fishing households (95%) have taken multiple adaptation strategies while the rest (5%) did not. The fishermen are exploited financially by the local credit facility provider. Diversification of livelihoods included agriculture (23.26%), fish trading (2.33%), fish farming (18.60%), and other different types of diversification found in the study area due to climate impacts but not always sufficiently fruitful. This situation may worsen over the next few decades and an improved level of responsiveness would be required.
 Vol. 9, No. 3, December 2022: 337-351

Application of HEC-RAS Model for Flood Inundation Mapping in Sungai Golok, Rantau Panjang

Flooding is a constant concern to achieve the Sustainable Development Goals (SDGs) in Malaysia, particularly in the state of Kelantan. This study focused on the issue of floods triggered by Sungai Golok from a hydraulics viewpoint. The goal of this study was to develop a flood mapping along Sungai Golok in Rantau Panjang town that specifically aimed at reducing floods and impacts on SDGs. The dry and wet areas on the flood mapping were simulated using Average Recurrence Interval (ARI) for a staggered period of 10 years, 50 years, and 100 years. An unsteady flow analysis was performed with the aid of the Hydrological Engineering Centre – River Analysis System (HEC-RAS). In addition to that, this study deployed the QGIS tool to develop and re-project an appropriate topographical profile of the Rantau Panjang region. It was determined that the value of 0.035 for the Manning’s was acceptable because all data for the initial calibration satisfies the condition of relative percentage difference RPD ? 25%. The HEC-RAS concluding outcome was calibrated and validated using statistical testing. The extent of the floods on 19 February 2016, and after 10 years later was found to be generally comparable in magnitude. After a period of 50 years, an increase in the discharge to 119 m3/s caused the flood's magnitude to expand at a faster rate. With a peak flow of 140 m3/s after a period of 100 years, it proved that the whole area will be inundated in floods. Highlighting these SDGs’ aim at achieving healthier lives and well-being of the inhabitants, the flood mapping is essential in the flood risk area to forecast the varying patterns of floods, which in turn used to ascertain the level of flooding in Rantau Panjang and subsequently reduce the impacts.

Kajian Kehandalan Saluran Drainase dengan Pendekatan Metode First-Order Second Momentdan Safety Factor

The growth and development of big cities in Indonesia is quite fast. Especially the city of Bandung which is the center of tourism in the West Java region. Ir. H. Juanda street is one of the access to tourism places in Bandung City and is an icon of Bandung City. In addition, Ir.H Juandastreet has problems, namely high levels of congestion and flooding in the rainy season. The last ten years the Jalan Ir.H. Djuanda always floods when there is heavy rain. This causes puddles of water to enter the Jalan Ir. H. Juanda section, namely from Pasar Simpang to Dago Terminal. This has an impact on road damage, drainage, and congestion. To determine the risk of overflow of the channel in the study area as a result of various amounts of flood discharge, carried outthree analyzes stages, namely hydrological analysis to determine the amount of return period discharge, hydraulic analysis to identify overflow points and improvement scenarios and reliability analysis using the safety factor and first-order-second moment methods. The results of the analysis show that there are 2 points that have the opportunity for overflow, namely at the location of the Al-Ihsan Mosque and the Honda Workshop. The solution given to overcome this is to normalize the drainage with a size of 1.5 m x 1.5 m from upstream to downstream.The results showed that the reliability of the channel increased to 92.96% (Two Years Return Period Discharge), 88.54% (Five Years Return Period Discharge) and 85.81% (Ten Years Return Period Discharge) for the Al-Ihsan Mosque channel and 100% (Two Years Return Period Discharge), 99.98% (Five Years Return Period Discharge) and 99.92% (Ten Years Return Period Discharge) for the Honda Workshop channel. The method in the risk analysis above can relate the probability of failure or exceedance to the expected success of the function of a drainage cross-sectional structure in accommodating flood flows.

Development of a smart sensing unit for LoRaWAN-based IoT flood monitoring and warning system in catchment areas

This study introduces a novel flood monitoring and warning system (FMWS) that leverages the capabilities of long-range wide area networks (LoRaWAN) to maintain extensive network connectivity, consume minimal power, and utilize low data transmission rates. We developed a new algorithm to measure and monitor flood levels and rate changes effectively. The innovative, cost-effective, and user-friendly FMWS employs an HC-SR04 ultrasonic sensor with an Arduino microcontroller to measure flood levels and determine their status. Real-time data regarding flood levels and associated risk levels (safe, alert, cautious, or dangerous) are updated on The Things Network and integrated into TagoIO and ThingSpeak IoT platforms through a custom-built LoRaWAN gateway. The solar-powered system functions as a stand-alone beacon, notifying individuals and authorities of changing conditions. Consequently, the proposed LoRaWAN-based FMWS gathers information from catchment areas according to water level risks, triggering early flood warnings and sending them to authorities and residents via the mobile application and multiple web-based dashboards for proactive measures. The system's effectiveness and functionality are demonstrated through real-life implementation. Additionally, we evaluated the performance of the LoRa/LoRaWAN communication interface in terms of RSSI, SNR, PDR, and delay for two spreading factors (SF7 and SF12). The system's design allows for future expansion, enabling simultaneous data reporting from multiple sensor monitoring units to a server via a central gateway as a network.

Preventing the Deluge: Climate Change, the Four Spheres, Interactions, and Causalities

Climate change means water change, and the impacts of climate change cause not only global sea levels to rise, but also elicit dangerous levels of coastal and mainland flooding. This study relates the effects of climate-change-induced sea level risings to several harmful, and sometimes preventable, factors causing floods. One topic discussed here will be the ocean’s current (more specifically, “The Atlantic Meridional Overturning Current”) as it continues to warm with increasing temperatures. In addition to discussing the effects of the AMOC, it also relates the increasing causes that are contributing to flooding, plus the proliferation of melt from ice sheets, ice caps, and glaciers, which inevitably contributes to the devastating effects of flooding on coastal communities, destroying habitats and contributing to the extinction of both aquatic and land animals, and even impacting human infrastructure and livelihoods. This examination additionally presents the serious implications that climate change and flooding have had on the planet’s freshwater resources and reserves, which are being further destroyed by the added influx of salt water, causing water to then be treated with aquifers, an energy-intensive and highly expensive process. Lastly, this paper provides several suggested possibilities for curbing some of the harmful effects humans have already had on contributing to climate change, as well as the environmental factors that have further caused dangerous levels of flooding.

Relationship between flood damage and repair methods for detached houses: Based on restoration works of flooded houses in Mihara City, Hiroshima prefecture, affected by heavy rains in July 2018

AbstractThis paper aims to clarify the relationship between flood damage and methods of repairing detached houses. The authors examined what repair works for each building part and element were performed in 11 surveyed houses flooded above the floor level, based on the field survey in Hiroshima Pref., an area heavily affected by a flood event in 2018 which included technical interviews with a regional building contractor. The findings indicate the repair methods for flood‐damaged houses were similar for those with similar inundation depths, and characterized by the depth of flooding rather than structural types. They analyzed the quantitative relationship between repair cost and flooding magnitude to develop a regression model using “flood water volume,” which is the product of the repaired floor area and the flooding depth above the floor, as the explanatory variable. The analysis shows the regression model was intuitively easy to understand and highly compatible. After confirming the qualitative and quantitative relationship between repair work and flooding magnitude, they considered simulated repair methods for a model house and analyzed cost fluctuations at four flood levels to present the two types of standard repair work: normal plan and minimum plan, that could be assumed for each flooding level.

The Risk of Flooding to Architecture and Infrastructure amidst a Changing Climate in Lake Baringo, Kenya

Climate change has grown more apparent in recent years with people becoming more aware of its potentially disastrous consequences. Flooding is one of the many consequences of a changing climate in Kenya known to cause immense devastation resulting in the loss of lives and property. This paper discusses the risk of flooding in Kenya as one of the many outcomes of climate change in the face of urgency to adapt Kenya’s built environment to flooding which is likely to continue to prevail in the decades as a result of the looming climate change. It also sought to evaluate the physical, traumatic, and psychological effects on communities affected by flood events. This cross-sectional survey, both qualitative and quantitative in nature, executed between 13th January 2021 and 14th July 2021 with 132 respondents along the western shoreline of Lake Baringo, near Marigat Town focused on the flood levels, structures, their materials, and quantities. Results show that the area covered by Lake Baringo increased by 18% from 236 km2 to 278 km2. The depth of floods ranged from 0.3 m to 1.2 m and exceeded 1.6 m during heavy rainfall up to 3.2 m with homes completely submerged by the lake. Flooding was experienced more by residents living in low areas nearer to the shoreline of the lake as compared to those living on higher grounds. 100% of the structures didn’t have the architectural technology to withstand the impacts of flooding with 59% of housing made of corrugated iron sheets both on wall and roofing, 22% of mud houses roofed with either corrugated iron sheets, 10% being timber with thatch and only 8% stoned walled houses. This predisposed all the residents to the harmful impacts of flooding. Piled sandbags by locals as a mitigating measure proved inadequate to withstand the forces of the rising waters. Flood walls were built around local lodges near the lake but the rising water level quickly breached these defences. The study recommends that county and national governing authorities develop flood adaptation strategies for resilience. These include long-term land-use planning, the establishment of early warning systems, evacuation plans, identification of vulnerable or high-risk populations, measures to ensure water quality, sanitation, and hygiene. Flood-resilient architecture including stilt and floating houses that mechanically rise and fall with respect to the highest water mark are recommended during flood events. Bridges on swollen rivers and resilient construction materials like reinforced concrete are to be used for sustainable development for flood risk adaptation.

Opportunities for planned retreat and flexible land use in Sweden: Local, regional and national governance perspectives

As the sea level rises and the frequency of intense rains increase, so does the need for climate adaptation. Planning for a successive development of society away from current and future flood prone areas to give room for water is not seen as an alternative in Sweden today, although it could be a strategy that creates long-term security.In this study, we investigated Swedish public authorities' perceptions of planned retreat and flexible land use. This was done through an online survey and interviews directed to officials directly involved in climate adaptation work, at municipalities, County Administration Boards (CABs), Regions, national authorities (NAs), and industry organizations (IOs). The responses were analyzed through the lens of a windows of opportunity approach. The study indicates that the extent to which climate scenarios are used and how far into the future the planning horizon extends in the practical work, varies between governance level which also have impact on the perspectives on planned retreat. The openness for planned retreat and flexible strategies seemed to differ slightly between governance levels in an ascending scale from regions, IOs / NAs, municipalities, to CABs. The survey has generated insights from a large number of respondents at different governance levels sharing their perceptions of retreat and adaptation in Sweden as a main contribution of this work.Difficulties to deal with uncertainties in climate scenarios and considering long-term perspectives were identified as some reasons that close the window for planned retreat. Enabling a flexible use of the land that will gradually become more exposed to flooding and sea level rise could be an intermediate step towards retreat. This would be a way to reframe a closed window of opportunity and begin the process of turning it into something transformative. It could be where the short- and long-term planning meet and a way to reframe our way of thinking about how we live and reside in dynamic waterfront areas, and perhaps lead to a more transformative, safe, and sustainable society for future generations.

Leaf acclimation to soil flooding and light availability underlies photosynthetic capacity of Lindera melissifolia, an endangered shrub of bottomland forests in the Mississippi Alluvial Valley, USA.

Lindera melissifolia is an endangered shrub indigenous to the broadleaf forest of the Mississippi Alluvial Valley (MAV). In this region, extant colonies of the species are found in periodically ponded habitats where a diversity of broadleaf trees can form well-developed overstory and sub-canopies-these habitat characteristics suggest that soil flooding and light availability are primary drivers of L. melissifolia ecophysiology. To understand how these two factors affect its photosynthetic capacity, we quantified leaf characteristics and photosynthetic response of plants grown in a large-scaled, field setting of three distinct soil flooding levels (no flood, 0day; short-term flood, 45days; and extended flood, 90days) each containing three distinct light availability levels (high light, 30% shade cloth; intermediate light, 63% shade cloth; and low light, 95% shade cloth). Lindera melissifolia leaves showed marked plasticity to interacting effects of flooding and light with lamina mass per unit area (Lm/a) varying 78% and total nitrogen content per unit area (Na) varying 63% from the maximum. Photosynthetic capacity (A1800-a) ranged 123% increasing linearly with Na from low to high light. Extended flooding decreased the slope of this relationship 99% through a reduction in N availability and metabolic depression of A1800-a relative to Na. However, neither soil flooding nor light imposed an additive limitation on photosynthetic capacity when the other factor was at its most stressful level, and the A1800-a-Na relationship for plants that experienced short-term flooding suggested post-flood acclimation in photosynthetic capacity was approaching the maximal level under respective light environments. Our findings provide evidence for wide plasticity and acclimation potential of L. melissifolia photosynthetic capacity, which supports active habitat management, such as manipulation of stand structure for improved understory light environments, to benefit long-term conservation of the species in the MAV.

Lora Technology for Flood Monitoring and Warn System

Flooding is the most frequent natural disaster that has an impact on humans. There is a history of widespread damage from floods. The organizations and competent authorities use a variety of sophisticated techniques to track the flood level in areas with a high risk of flooding. The majority of these devices are quite expensive to use and maintain. In the proposed system, data from sensors including those measuring water level, water flow, and ultrasonic sensor can be sent to the cloud using a GSM device. If environmental condition threshold values rise, a warning message will be sent to the relevant authorities, who will then inform the residents of the flood-prone area. With the aid of such a system, both commercial and public organizations can develop their flood mitigation strategies before the situation worsens. The most widely used mobile messaging platform, the Global System for Mobile Communication (GSM), is used to send the SMS to the villages as a warning simultaneously a buzzer will ring which is placed in every village of the flood-prone area. This buzzer will work with the technology of LoRa transceiver, which had a long range of communication.

Effects of sluice gate operation on sediment flushing in Bekasi weir using a 1D numerical model

Sedimentation upstream of a weir is a common phenomenon, especially for a river with high sedimentation. In the long term, this can lead to problems since the discharge capacity will decrease due to the rise of the riverbed, as experienced in Bekasi Weir, West Java, Indonesia. The upstream accumulated sediments increased up to 1.5 m from its original riverbed in a decade. One of the easiest ways to overcome this issue is to return the riverbed elevation to its actual elevation by manual excavation or sediment flushing using a sluice gate. This paper discusses the effects of operating three sluice gates of the Bekasi Weir for flushing the deposited sediments. The analysis was carried out through 1D modeling using MIKE-11 software to analyze the morphological effects after flushing the sediments with variations of sluice gate opening scenarios. Finally, it was found that without any manual excavation, the flushing method with one fully-opened gate was the best solution by giving a significant upstream bed degradation of up to 1 m, reducing the upstream flood level, and maintaining the upstream-downstream freeboard. The solution could be more effective when combined with river normalization.

UAV-Based Floodwater-Level Establishment for FEWS for Abrupt River Section Change in Imsan

Flood damage has been increasing owing to climate change; thus, a flood early-warning system (FEWS) has been established to evacuate residents safely in flood-prone areas. The FEWS is a fundamental nonstructural system that reduces human and material damage caused by floods. The damage can be minimized when appropriate settings are used. In general, the need for an early warning is determined using a water gauge installed on a bridge. If there is an abrupt change in the river section near the bridge, an alarm is issued based on the water-level gauge on the bridge. However, some areas may be more vulnerable to flooding than where the bridges exist. In these cases, vulnerable areas can be inundated by floods before a warning alarm is provided. The current study area of the Chogang-cheon River is such an area. Therefore, an unmanned aerial vehicle (UAV)-based remedy is proposed to overcome the discrepancy between the flooding water levels of the gauge location and the vulnerable area. First, spatial information about the river cross section was obtained through a UAV for the study area. As a result of Pix4D processing after river surveying by the UAV, a noticeable abrupt river width change section was confirmed, particularly upstream of the Gwangi Bridge in the middle of the Chogang-cheon River. Then, the level of the bridge and the upstream point of the bridge for the same flow rate were calculated using the Hydrologic Engineering Center River Analysis System (HEC-RAS) program. Through this remedy, the section of the river where flooding occurs first was defined, and an appropriate flood early-warning water level was appropriately estimated. The approach in this study can be widely applied to rivers where a FEWS is needed to determine where rivers change abruptly.

Hydrologic and geomorphic effects on the reduction of channel discharge capacity in the Middle Yangtze River

A systematic increase in the occurrence of flood events has been noted in rivers worldwide. However, our understanding remains unclear of how the flood level is affected by the change in channel discharge capacity. Therefore, the reduction of channel discharge capacity was quantified in the Middle Yangtze River (MYR) based on extensive measured data. It is confirmed that the variation in channel discharge capacity is a superposition result of channel-morphology and channel-resistance changes, as well as the change in local base-level at the outlet. Then a series of numerical simulations were carried out to quantitatively identify the contribution of each factor to the reduction of channel discharge capacity in the MYR for the years of 2004 and 2020. Simulated results reveal that channel degradation increased the flow passage area, helping the channel to convey floods, with the effect being weakened along the reach; however, the decline in flood level under the same discharge was not observed, which was primarily attributed to the increases in channel resistance and local base-level at the outlet. These two factors accounted for 16–91 % and 9–84 % of the total impact at four hydrometric stations in the MYR. It should be noted that the dominant factor to influence the discharge capacity varied greatly at different stations, which depended on the degree of bed-material coarsening, the distance from the confluence of lakes, etc. At the stations immediately downstream of the dam, the contribution of the increased movable bed roughness usually played a more essential role; while at the stations close to the outlet with the confluence of large lakes, the increase in local base-level became the main factor that accounted for the rise of high-flood levels under the specified large discharge.

Assessing and Mitigating Ice-Jam Flood Hazards and Risks: A European Perspective

The assessment and mapping of riverine flood hazards and risks is recognized by many countries as an important tool for characterizing floods and developing flood management plans. Often, however, these management plans give attention primarily to open-water floods, with ice-jam floods being mostly an afterthought once these plans have been drafted. In some Nordic regions, ice-jam floods can be more severe than open-water floods, with floodwater levels of ice-jam floods often exceeding levels of open-water floods for the same return periods. Hence, it is imperative that flooding due to river ice processes be considered in flood management plans. This also pertains to European member states who are required to submit renewed flood management plans every six years to the European governance authorities. On 19 and 20 October 2022, a workshop entitled “Assessing and mitigating ice-jam flood hazard and risk” was hosted in Poznań, Poland to explore the necessity of incorporating ice-jam flood hazard and risk assessments in the European Union’s Flood Directive. The presentations given at the workshop provided a good overview of flood risk assessments in Europe and how they may change due to the climate in the future. Perspectives from Norway, Sweden, Finland, Germany, and Poland were presented. Mitigation measures, particularly the artificial breakage of river ice covers and ice-jam flood forecasting, were shared. Advances in ice processes were also presented at the workshop, including state-of-the-art developments in tracking ice-floe velocities using particle tracking velocimetry, characterizing hanging dam ice, designing new ice-control structures, detecting, and monitoring river ice covers using composite imagery from both radar and optical satellite sensors, and calculating ice-jam flood hazards using a stochastic modelling approach.

Flooding Hazard Assessment of Built-Up Lands Using Modern Geographic Information Systems

Introduction. The construction and operation of buildings and structures on the banks of rivers and other water reservoirs with rapidly changing water level are associated with the hazard of territories flooding and underflooding, which can lead to major material damage and even endanger the life and health of people. It’s very important to make a reliable forecast of floodable and underfloodable zones and to develop possible engineering protection measures for such territories, as well as evacuation or rescue plans for cases of emergency. In this article by the example of 2 allocated for construction potentially flooded plots in the Tuapse district of the Krasnodar region, the quantitative flooding hazard assessment is carried out based on the use of the geographic information system QGIS.Materials and methods. In the study there were used: the analysis of existing methods for assessing underflooding and flooding of territories; the long-term observation materials of the water level in rivers and of the largest floods on the studied plots; the analysis of methods of engineering protection of territories from underflooding and flooding; the hydrogeological and hydrological processes modeling using the modern geo information system QGIS; the development of recommendations for engineering protection of the built-up lands and for design of buildings’ and structures’ bases and foundations.Results. As a result of modeling of the underflooding and flooding processes of 2 plots of the prospective built-up lands of the Tuapse district of Krasnodar region in the geo information system QGIS, the boundaries of potential flooding zones and varying probability water rise levels have been identified. Graphical results of modeling in the QGIS system have been presented and graphs of flooding and underflooding levels have been plotted in given sections and along plot’s outline.Discussion and Conclusions. The boundaries of the most hazardous built-up lands have been identified and the engineering protection measures have been reasoned for them. Recommendations have been developed on design and construction of buildings and structures on the plots taking into account the forecasted hazards of underflooding and flooding.

Probable maximum tropical cyclone parameters for east and west coast of India

Storm surge simulation models require certain parameters for evaluating the worst possible event that could occur at a site with respect to a certain return period. The most significant probable maximum tropical cyclone parameters are pressure deficiency at the centre (ΔP) and maximum wind speed (Vmax) during the cyclone. In this study, the probable maximum tropical cyclone parameters that would yield the maximum probable storm surge along the Indian coasts of Arabian Sea and Bay of Bengal are estimated. Datasets are created based on various existing data archives for each basin. The datasets are subjected to extreme value analysis for determining the ΔP and Vmax parameters. The data are fitted to various probability distributions (Gumbel, Fréchet, Weibull and Log-normal) whose parameters (scale, shape, and location parameters) are estimated using graphical (least square fit) and numerical (order statistics approach) methods. A mean recurrence interval of 1000 and 10,000 years is considered for strategic structures. The best fit distribution and its parameters are obtained based on goodness of fit criteria. The resulting ΔP and Vmax are compared with theoretical maximum cyclone parameter values of each basin and revised till an optimal set of values are reached. The analysis shows that ΔP and Vmax values for Arabian Sea and Bay of Bengal are best represented by Weibull distribution. The estimated parameters are useful input to a storm surge model to determine the design basis flood level for the strategic coastal sites.