The article presents a methodology for determining the value of the expansion coefficient of a reconsolidated caving zone in the context of forecasting the rise in underground mine water levels and consequent surface subsidence caused by the process of flooding the closed coal mines. The paper also provides a brief characterisation of analytical predictive models regarding surface subsidence during the process of flooding coal mines. In order to describe the vertical deformation of the reconsolidated porous rock mass in the caving zone, a linear-elastic medium of Biot was utilised. The conducted theoretical calculations demonstrate a high agreement with the results obtained through the identification of the expansion coefficient parameter based on the analysis of in-situ subsidence measurements in Dutch and German mining areas. The proposed methodology was applied to a real case study involving the forecasting of the impact of the flooding process on the underground workings of the German Ibbenbüren mine. The article constitutes a significant contribution to the field of forecasting the rise in underground mine water levels and surface subsidence during the process of flooding closed coal mines. The presented methodology and obtained results can be valuable for researchers, engineers, and decision-makers involved in the planning and management of mining areas.
Due to advanced silting, the Foum El-Gherza dam has lost more than two thirds of its initial capacity (47 hm3) and is no longer able to withstand the floods that threaten its downstream section. Indeed, the damage recorded in recent years has confirmed the vulnerability of the man-made structures located on both banks of the Oued Labiod. Thus, we believe that the hydrological behaviour of the catchment area is no longer influenced by the dam. Therefore, the hydrological study involved a critical analysis (homogeneity tests) of the hydro-climatic data in order to highlight the characteristics of the historical events recorded during the period 1950–2019. The frequency study of the maximum daily rainfall and floods recorded at the dam allowed us to determine the rainfall and flow rates of the return periods (10, 25, 50, 100, 500 and 1000 years). The flooding of the 28 October 2011 were used as a standard for the calibration of the model calculated by the HEC-Ras software. After validation of the model, a prediction of the water levels and flood extent was made for the selected return periods. The results obtained show that a part of the town of Seryana (district located on the edge of the right bank) suffers from flooding proportionally to the return periods of the floods. In addition, some agricultural areas bordering the Oued are also affected by the floodings. The hazard modelling maps can be considered as a basis for a flood risk prevention plan (PPRI) and as a decision support tool.
Powodzie to jedna z najczęstszych i najbardziej niszczycielskich klęsk żywiołowych na świecie, które mają negatywny wpływ na ludzi, środowisko i gospodarkę. Artykuł ma na celu modelowanie i ocenę ryzyka powodziowego wykorzystując jednowymiarowy model HEC-RAS oraz otwarte dane udostępniane przez Główny Urzędu Geodezji i Kartografii. Obszar badań obejmuje Kazimierz Dolny położony nad Wisłą. Badania przeprowadzono w trzech etapach. Po pozyskaniu danych z numerycznego modelu terenu i elementów doliny rzecznej (np. przekrojów poprzecznych doliny) oraz opracowaniu warstwy szorstkości na podstawie wskaźników Manninga, wymodelowano wody wezbraniowe dla powodzi dziesięcio-, stu- i pięćset letniej. Analiza ryzyka wykazała, że powódź 100-letnia powoduje już dość znaczne szkody w dobrach ludzkich i kulturowych, a powódź 500-letnia znacznie je powiększa, niszcząc 2016 budynków i zalewając obszar o powierzchni niemalże 207 ha.
EN
Flooding is one of the most frequent and devastating natural disasters in the world, generating negative impact to people, environment and economy. The paper aims in flood risk modelling and risk assessment based on one-dimensional HEC-RAS model and open data derived form the Head Office of Geodesy and Cartography. The research area covers the small historic city Kazimierz Dolny located on the Vistula River. The research was carried out in three stages. After digital elevation model and river valley elements (e.g. valley cross sections) data acquisition, as well as elaborating a roughness layer based on Manning's indicators, the ten-, one-hundred- and five-hundred-year floods water were modelled. The risk analysis showed that the 100-year flood is already causing quite significant damage to human and cultural assets, and the 500-year flood significantly increases it, destroying 2,016 buildings and flooding an area of almost 207 hectares.
W artykule poruszono problem uszkodzeń popowodziowych budynków i budowli, ich skutecznego diagnozowania oraz przywracania do wymaganego stanu użytkowego. Za przykład posłużyły tu dwa okresy powodziowe, lipiec 1997 r. i czerwiec 2010 r. Wskutek naporu wód powodziowych na sąsiadujące ze sobą obiekty budowlane skala powstałych w nich uszkodzeń nie była jednakowa. Autorzy podjęli próbę udzielenia odpowiedzi na pytanie: od czego zależał zakres uszkodzeń budynków i ich elementów składowych, a także zakres późniejszych napraw lub podejmowane decyzje o rozbiórce i czy przed takimi skutkami oddziaływań będzie można ustrzec się w przyszłości? Na czym polegał (jakie stosowano metody) i jak długo trwał proces oczyszczania oraz wysychania przegród, które wchłonęły spore ilości zanieczyszczonej chemicznie i bakteriologicznie wody? Na wybranych przykładach zostanie również opisany proces rewitalizacji uszkodzonych budynków.
EN
The article deals with the problem of flood damage to buildings and structures, their effective diagnosis and restoration to the required operational condition. Two flood periods, July 1997 and June 2010, served as an example here. Due to the pressure of flood waters on adjacent building structures, the scale of damage to them was not the same. The authors attempted to answer the question: what did the extent of damage to buildings and their components depend on, as well as the scope of subsequent repairs or the decisions made about demolition, and whether it would be possible to avoid such effects in the future? What was it (what methods were used) and how long was the process of cleaning and drying the partitions, which absorbed large amounts of chemically and bacteriologically contaminated water? The process of revitalizing damaged buildings will also be described on selected examples.
Rainwater management is one of the important problems of cities. At very strong downpours, storm sewer systems may not capture the rainwater, which floods pavements and roadways. The water flushes fuel and oil traces after vehicles, fallen debris, and other pollutants, which will be moved to the ground, ponds, rivers, seas, etc. In past, the problems were solved using engineering approaches – a set of rainwater receivers, a duct network, and at best, wastewater treatment plants. Now, the sponge city concept is a better solution that uses a biotechnological way for throttling water flows, drainage, and purifying them. The work aims to improve the design of roads to fully absorb rainwater from them with maximum convenience for road users. We propose a design of roads using special “green structures” – rain-garden bands along the sides of roadways. We tested its ability of water capturing on the example of Kyiv city by matching the ability with the strongest precipitation observed. In addition, the proposed plants can extinguish the energy of bouncing cars during road accidents for the protection of pavements.
Powodzie zimowe, związane z zatorami lodowymi, są coraz częściej traktowane jako zjawisko rzadkie lub całkowicie wyeliminowane. Opisana w artykule sytuacja pokazała, że zator nadal może prowadzić do poważnego zagrożenia powodziowego, bardzo trudnego do zneutralizowania. Omówiono sytuację hydrologiczną zimą 2021 r. oraz przyczyny gwałtownego wzrostu ilości lodu w korycie Wisły w rejonie Płocka. Przedstawiono również wyniki pomiaru wypełniania koryta rzeki lodem. Prześledzono proces formowania się zatoru, jego konsekwencje oraz akcję lodołamania. Zwrócono uwagę na postępujące wypłycanie się zbiornika.
EN
Winter floods related to ice jams are increasingly often treated as rare or definitely eliminated phenomena. Situation described in the article indicates that jams may still constitute a serious flood threat, which is very difficult to neutralise. The article discusses the hydrological situation in winter 2021 and the reasons behind sudden accumulation of ice in the Vistula riverbed in the Płock region. It also presents the results of measurement of the riverbed filling with ice. The authors described the jam forming process, its consequences and the ice-breaking action. They also pointed out to the progressing reservoir shallowing.
Sanitary sewage network is relatively rarely considered as the cause of urban floods. Its hydraulic overload can result not only in flooding, but also sanitary contamination of subcatchments. Stormwater is the main reason for this overload. In contrast to the stormwater or combined sewer system, these waters infiltrate into the network in an uncontrolled way, through ventilation holes of covers or structural faults and lack of tightness of manholes. Part of stormwater infiltrates into the soil, where it leaks into pipelines. This greatly hinders assessing the quantity of stormwater influent into the sanitary sewer system. Standard methods of finding correlation between rainfall and the intensity of stormwater flow are ineffective. This is confirmed, i.a. by the studies performed in an existing network, presented in this paper. Only when residuals analysis was performed using the ARIMA and ARIMAX methods, the authors were able to develop a mathematical model enabling to assess the influence of rainfall depth on the stormwater effluent from the sewage network. Owing to the possibility of using the rainfall depth forecasts, the developed mathematical model enables to prepare the local water and sewerage companies for the occurrence of urban floods as well as hydraulic overload of wastewater treatment plants.
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In the eastern Mediterranean region of the Middle East and North Africa, pluvial flooding has become a common and severe climate change consequence event that requires immediate attention. The Wadi-Gaza basin is a critical source of surface water in Palestine; nevertheless, climate change and anthropogenic processes are altering the basin’s hydrological features, resulting in a series of extreme and disastrous flooding events in the coastal plain at the basin downstream. The Mann–Kendall test, Sen’s slope estimator, and the IPTA method that was used to analyze historical rainfall in the basin from 1979 to 2013 refer to a declining trend pattern, which reduces the surge of runoff discharge. Moreover, the future projection for the total monthly rainfall under the ensemble model of CIMP5 for the RCP scenarios of 2.60, 4.50, and 8.50 demonstrate a general decreasing trend in the rainfall with a variation ranging between about − 36 and − 53%. The frequency analysis for the maximum daily rainfall using different computing approaches shows that the theoretical maximum rainfall values for the assessment of flooding events were assigned to 22, 31, 35, 45 52, 59, 66, and 77 mm for the whole basin for the return periods (T) of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively. The land cover–land use of the basin shows that 51% is barren land while the other portion is divided between urban (~16%), agricultural (~ 13%), and natural (~ 20%) lands. However, the type of soil that covers the basin is classified mainly as clay, loam, and sandy clay. According to the hydraulic analysis of downstream flooding, the volume of surge water that might reach the coastal plain in the event of water storms of 22 and 77 mm is around 6 and 118 million cubic meters, respectively. The area at risk of inundation due to foods in the Wadi-Gaza is between 3 and 17 km2 , covering around 5–29 percent of the Gaza Strip’s middle governorate area, respectively.
W artykule, który stanowi II część publikacji (Gospodarka Wodna 6/21 str. 9–16) przedstawiono przyczyny i przebieg powodzi miejskiej w Gdańsku, jej skutki w różnych miejscach Gdańskiego Węzła Wodnego oraz doraźnie wykonane naprawy zniszczonej infrastruktury miejskiej. Bezpośrednią przyczyną powodzi był intensywny opad deszczu skoncentrowany głównie na obszarze zlewni Kanału Raduni (KR), przebiegającego u podnóża wzgórz morenowych i wzdłuż szlaku komunikacyjnego prowadzącego do Gdańska. Zlewnia KR uległa w ostatnich latach intensywnej urbanizacji, co spowodowało uszczelnienie jej znacznej powierzchni i przyspieszenie spływu powierzchniowego.
EN
The paper, which is the 2nd part of the publication (Gospodarka Wodna 6/21 pp. 9–16), presents the reasons and the run of urban flood in Gdańsk, its results in various parts of Gdańsk Water Node and immediate repairs of damaged city infrastructure. The basic cause of the flood was a very intensive rainfall concentrated on the catchment of Radunia Channel (RCh) which runs at the foot of morraine hills and along the main road leading to Gdańsk. The catchment of RCh was in recent years intensively urbanized, what resulted in the sealing of the terrain and accelerating of surface runoff.
Prezentowana I część artykułu Zagrożenia powodziowe Gdańska obejmuje opis Gdańskiego Węzła Wodnego, w skład którego wchodzi system rzek i kanałów wraz z istniejącą infrastrukturą hydrotechniczną w postaci progów, jazów i przepustów. Na tym obszarze, w lipcu 2001 r. wystąpiła powódź błyskawiczna, spowodowana intensywnym opadem deszczu. Przedstawiono charakterystykę elementów wchodzących w skład GWW oraz warunków przepływu.
EN
This 1st part of the article entitled Flood threat to Gdańsk describes the Gdańsk Water Note, composed of a system of rivers and channels together with the existing hydraulic infrastructure including sills, weirs and culverts. In July 2001, a flash flood occurred in this area, caused by intensive precipitations. The article presents the characteristics of GWN’s elements and the flow conditions.
The main objective was to explore the connection between flood and drought hazards and their impact on crop land and human migration. The Flood and Drought effect on Cropland Index (FDCI), hot spot analysis and the Global Regression Analysis method was applied for the identification of the relationship between human migration and flood and drought hazards. The spatial pattern and hot and cold spots of FDCI, spatial autocorrelation and Getis-OrdGi* statistic techniques were used respectively. The FDCI was taken as an explanatory variable and human migration was taken as a dependent variable in the environment of the geographically weighted regression (GWR) model which was applied to measure the impact of flood and drought hazards on human migration. FDCI suggests a z-score of 4.9, which shows that the impact of flood and drought frequency on crop land is highly clustered. In the case of the hot spots analysis, out of seventy districts in Uttar Pradesh twenty-one were classified as hot spot and eight were classified as cold spots with a confidence level of 90 to 99%. Hot spot indicate maximum and cold spots show minimum impact of flood and drought hazards on crop land. The impact of flood and drought hazards on human migration show that there are fourteen districts where migration out is far more than predicted while there are ten districts where migration out is far lower.
Floods are a great concern for people and infrastructure, and this is an is‑sue which has increased in several regions around the globe in recent years. This study aims to evaluate flood risk areas and create a flood risk map using in‑tegrated remote sensing data and a geographic information system (GIS) in the Wasit governorate – eastern Iraq. Specifically, GIS‑based multi‑criteria analy‑sis (MCA) was used to map flood hazard areas using a four‑criteria layer which is as follows: flow accumulation, slope, rainfall, and elevation. These four layers are standardized and combined using the overlay approach in ArcGIS software and a final map was produced. The study area was divided into five zones based on the results map, namely: very low, low, medium, high, and very high, according to the flood risk area. The resulting map indicates that over 60% of the study area is likely to experience a high and very high level of propensity of flooding. This study could be useful for government planners and decision‑makers to predict potential flooding areas and enhance flood management plans.
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Na przestrzeni wieków mieszkańcy Żuław Wiślanych zmagali się z licznymi powodziami. Wiele z nich powodowało katastrofalne zniszczenia. Powódź z 1888 roku nie była największą, ale przyśpieszyła realizację odkładanych od 127 lat inwestycji, mających ograniczyć skutki występujących powodzi. W efekcie wykonano w 1895 roku nowe Ujście Wisły do morza, przebudowano obwałowania jej oraz Nogatu. W okolicy Mątowskiego Cypla dokonano kolejnej zmiany podziału rozpływu wód tych rzek.
Wędrując w czasie po Żuławach Wiślanych nie trudno dostrzec wszech obecnej wody, przyczyniającej się do urodzaju i bogactwa tych ziem. Niestety żyzne tereny delty Wisły przez wieki narażone były również na niszczycielskie działanie jej nadmiaru. Skutkiem były liczne powodzie wywierające piętno w naturalnym środowisku.
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Floods are the most frequent and most distractive natural disaster around the globe. Pakistan is facing frequent flooding since 1929 and foods in the Indus river basin cost more than 7000 lives and caused mighty changes in land use and land covers (LULC) since 1947. District Layyah hit by food on August 1, 2010. Landsat ETM+ with 30 m spatial resolution was utilized to investigate the LULC changes in district Layyah for the 2010 food. It was revealed water area increased 8.05% from July 3 (379.13 km2 ) to August 20 (656.02 km2 ) in district Layyah. Vegetation cover increased from 1149.62 km2 on July 3 to 1842.23 km2 on August 20 in district Layyah and showed a 20.13% increment. Barren/built-up area showed a decrement of 28.18% from 1911.72 km2 in pre-food analysis to 941.90 km2 in the post-food analysis. Total 15 union councils (UC) of district Layyah were affected by food from which 10 lies in tehsil Layyah and 5 belongs to tehsil Karor Lal Esan. Flood affects 177 settlements in district Layyah from which 156 belong to tehsil Layyah and 21 were from tehsil Karor Lal Esan. These results suggest that the impacts of the food on LULC need more attention to cope with the challenge of frequent flooding and impacts in Pakistan.