Flood Protection Project Research Articles

Managing stakeholders for implementing innovations: The case of a flood protection project in Kenya

Innovative projects, such as those for flood protection in developing countries, are urgent, stakeholder intense, and need to be carried out even in contexts where sufficient governance frameworks are not in place. This research seeks to understand how innovative projects can be implemented in weak institutional contexts by focusing on managing stakeholders in the single in-depth case study of the implementation of the SLAMDAM innovative project in the Isiolo County in Kenya. Following the analysis of 12 semi-structured interviews with 27 different stakeholders and 7 observations of stakeholder interactions, we answer the following questions: 1) what are the challenges during implementation of the innovation projects in weak-institutional contexts? 2) how are these challenges addressed through strategies? 3) how can we theorize the relationship between challenges and strategies in weak institutional contexts? The challenges include community resistance, information fragmentation, disjoined efforts, and governance inefficiency. Theoretically, we highlight how ad-hoc workarounds are operationalized in weak-institutional contexts and how they can lead to lasting changes by building governance frameworks in the long term. Practically, this research offer valuable guidance for practitioners involved in innovative projects, particularly in developing countries with weak institutional frameworks.

Precipitation Study in Flood Zones: San Mateo Atenco, State of Mexico, Mexico Case Study

This work is focused on analyzing the causes of flooding in the sub-basin belonging to the municipality of San Mateo Atenco: Almoloya-Otzolotepec, because the municipal territory is constantly threatened by hydrometeorological phenomena, such as hailstorms, frost and torrential rains. The maximum precipitation was analyzed in neighboring climatological stations and the precipitation at different return periods (2 to 1000) was determined through the Gumbel distribution, and its impact according to the Thiessen polygon method. With the information of the 24-hour intensities, the Intensity Duration Frequency (IDF) curves and the hietogram of the study area were plotted using the alternating block method. The above procedure was applied to the precipitation data from the 9 stations that affect the basin. The approach proposed in this work considers all the precipitation variables for the best approximation of the phenomena that may occur in the basin; it is an innovative model because it considers the weighted averages of precipitation for each area of influence and its surroundings; this information is useful for the implementation of flood protection projects, adequate design of drainage and sewage systems, and a rational use of the resource to guarantee better living conditions for the inhabitants. According to the results obtained, there is a slow hydrological response and the areas with the greatest runoff potential (8383<CN<100) are located towards the central part of the basin where there is a significant concentration of bare soil.

Climate Change Impact on the Trigger of Natural Disasters over South-Eastern Himalayas Foothill Region of Myanmar: Extreme Rainfall Analysis

The study examines the characteristics and variability of monsoon rainfall in Myanmar, focusing on the relationship between heavy rainfall, floods, and earthquakes, which impact agriculture, hydrology, and the environment. Generally, heavy rainfall can cause flooding, economic losses, and water table changes. Northern Myanmar floods occur mainly during the monsoon season from June to October and can be classified into widespread floods along major rivers like Ayeyarwady, Thanlwin, Chindwin, and Sittoung and flash floods in small streams and rivers. Climate change is expected to increase the frequency and intensity of extreme weather events, including heavy rainfall, which can trigger floods or landslides, which also can in turn cause earthquakes. Heavy rainfall over northern Myanmar and the Sagaing faults, which are the main triggers of earthquakes, has been the subject of several studies. The study uses the Copernicus 5 database of global climate model (GCM) simulations with two scenario analyses on climate change detection and indices (ETCCDI) to study changes in climatic extremes. Results show high intensity in the northern region and monsoon core regions, while the central region shows less intensity. The study also uses intensity-duration-frequency (IDF) curves to analyze the relationship between rainfall duration, intensity, and return time in major risk zones. The study finds that as short duration lengthens, rainfall intensity increases for future rainfall patterns. This information is expected to be convenient for local authorities and flood protection projects in rural and urban basins.

Reducing flood risk and improving system resiliency in Sacramento, California: overcoming obstacles and emerging solutions

Sacramento, the capital of California, has a population of over 2 million and is one of the most flood prone regions in the nation. Its problems exemplify those of many urban communities built near riverine and deltaic systems, that are subject to climate change. The city and its surrounding communities are protected by an elaborate system of levees and flood bypasses; but aging infrastructure, expected increases in extreme wet weather, and projected sea level rise are increasing the risk of levee failures. We explore how flood management approaches including social/institutional (non-structural), traditional structural, and ecological based approaches are being implemented in the Lower Sacramento/North Delta Region amid significant obstacles, to build resilient flood management systems. We review four case studies, one structural levee project and three multi-benefit projects that are only recently being implemented. We also examine the barriers, constraints, and challenges for implementing flood protection projects, and how project proponents are collectively working through these obstacles. We conclude that significant progress has been made in building flood resiliency since the 2008 Central Valley Flood Protection Act and the release of the 2012 Central Valley Flood Protection Plan. Informational tools and policies are being developed to educate the public and prepare for floods. Structural levee investments are substantial and are being implemented through partnerships. Statewide policies and investments are increasingly supporting multi-benefit projects that incorporate ecological restoration/enhancement while expanding flood volume capacity. Progress on implementing multi-benefit projects has been slow, due to land acquisition, easements, funding, regulatory and construction challenges; however, solutions to these impediments are emerging to facilitate more rapid progress. It is essential to continue and intensify the progress made in the last two decades, by learning from past projects, and improving on existing pathways to implement sustainable projects at a faster rate.

Discount Rate Selection for Investments in Climate Change Adaptation and Flood Risk Reduction Projects

The selection of an appropriate discount rate is a critical yet often neglected aspect of valuing flood protection and climate adaptation projects. We examine current discounting practices in flood risk management and climate adaptation literature and compare these practices with a proposed fair market value (FMV) discounting approach, in which we discount project cash flows based on their levels of systematic market risk, consistent with practice in the private sector. Using publicly available data, we demonstrate minimal correlation between flood risk–related cash flows and overall market returns, suggesting flooding-related cash flows are most appropriately discounted near the risk-free rate. We consider the example of a proposed storm surge barrier in Boston Harbor and compare prevailing public-sector discounting approaches with this FMV approach. Our results suggest prevailing discounting approaches systematically undervalue flood risk reduction benefits and climate adaptation investments relative to the private-sector valuation implied via the FMV approach.

Amelioration of acid sulphate soils in Nilwala river basin

Paddy tracts of Nilwala basin has been affected by the implementation of Nilwala Flood Protection and Drainage Project in 1979 due to excessive drainage, and nearly 7000 acres of land is abandoned. The water table goes down to the level of 50 cm below soil surface during dry periods and soil pH falls to 3-4 causing acid sulphate condition. Hitherto several efforts have been made to ameliorate the paddy lands but no any economical solution is obtained. The National Science Foundation project to find out the feasibility of using natural hydraulic forces to increase water table to keep the acid sulphate forming minerals at bay and to cultivate rice in these paddy lands. Water table fluctuation in relation to water level in the drainage channel was studied over one year and there was found a very high correlation (r2=0.985) indicating a possibility of increasing water table by heading up water in the channel. Simulated pot experiment showed that increasing water table to 15 cm below soil surface allows rice to grow effectively, showing plant survival of 112 (53%) compared to 28 (15%) plants in control. Recorded plant height of Bg. 357 variety was 35 cm compared to 22 cm in different treatments and control, respectively. Soil pH also increased to a value closer to 6.0 in the treatment which is conducive for rice cultivation. However, the low values of plant survival and plant heights were due to unusual extreme low rainfall in 2020/21 Maha season compared to 10 years’ average. SAARC J. Agric., 20(2): 211-221 (2022)

Flood hazard assessment in a mountainous river basin in Thessaly, Greece, based on 1D/2D numerical simulation

• Flood inundation and hazard maps, under steady and unsteady flow conditions based on GIS and 1D/2D flow model usage, were generated. • Proposed methodology was based on a comparison between different transform methods. • Flood hazard maps creation is necessary for the positioning and planning of appropriate flood protection projects. • Comparison between 1D/2D numerical results. Floods are amongst the greatest natural hazards in the world. In the last decade, many flood events have been observed and recorded in Greece, which have had a direct effect on river ecosystem consistency. Flood hazard assessment is a critical parameter for flood hazard areas identification and for taking relevant mitigation measures to prevent the hazard. Therefore, the study and evaluation of streams’ hydraulic behaviour is necessary for flood management. The aim of this research work is to present a substantial methodology for flood hazard management based on GIS and hydrological/hydraulic numerical models. Flood inundation and flood hazard maps in a stream area under steady and unsteady flow conditions, using one–dimensional and two–dimensional flow models were generated, as an extension of the European Directive 2007/60/EC. For unsteady flow simulations, a hydrograph was used, based on the available rainfall data of the flood occurrence period. The simulation under steady flow conditions was performed for return periods of 100 and 1000 years. Numerical results of one–dimensional and two–dimensional numerical models were adequately compared with available field measurements providing the reliability of the current methodology.

Flow structure and grain motion assessments of large river widening in a physical model using ultrasonic Doppler velocity measurements

Local river widening aims to reduce the flood risk and enable the self-morphodynamic development of the river. However, a large amount of transported sediments settles due to the flow velocity reduction in the widening. Assessing the flow and the grain motion is therefore a key factor to the sustainability of a local river widening project. The grain motion depends on the ratio between tractive forces and resisting forces, which can be evaluated through the local shear stress. The most common method to estimate shear stress in uniform flows is to determine the shear velocity based on the logarithmic distribution of velocity over depth. This involves knowing the velocity profile and in turn the flow structure. In the present study, morphodynamic tests are conducted to explore the hydrodynamics and the grain motion of a local river widening in the framework of the 3rd correction of the Rhone River, the largest flood protection project in Switzerland so far. The ultrasonic velocity profiler method is used to measure velocity profiles at two selected cross-sections. The obtained velocity profiles allow for the assessment of local shear stress on the mobile riverbed. The results show a non-uniform distribution of the flow and the shear stresses. The flow conditions at the preferential channel are more favorable to grain motion compared to those at the river’s edges.Graphical abstract

Customising flood damage functions to estimate the carbon footprint of flood‐related home repairs

AbstractFlood damage functions are important tools used to estimate potential damage to the built environment from various types of flood‐related hazard events (e.g., hurricanes, riverine flooding). Oftentimes these damage estimates are used to determine the feasibility of flood protection or mitigation projects or to plan for future disasters. While existing standardised functions are used to estimate potential economic loss for residential buildings, functions can be customised to assess the environmental impacts of flood damages for specific building designs. This study presents a methodology for customising functions to estimate the carbon footprint of flood‐related building repairs. Unlike regular home repairs, which are based on material life expectancy, flood repairs are dependent on the severity of the flood hazard (i.e., flood depth) and probability of hazard occurrence within the lifespan of a building. To demonstrate the methodology, customised functions are developed for a case study home design in Saint Petersburg, Florida.

The Smart Rivers approach: Spatial quality in flood protection and floodplain restoration projects based on river DNA

AbstractMany river rehabilitation projects have been implemented in the past 30 years, strengthening the natural dynamics and ecology of river systems, while reconciling the functions of flood protection, navigation, sediment extraction, and cultural identity. Still, the planning and design of floodplain projects is subject to debate on how to best follow the “natural” characteristics of specific river stretches, the “DNA of the river.” Unlike many other approaches of integrated river management, this approach entails a design strategy for spatial quality in river floodplain development projects at local and regional level, where the current discharge characteristics of the upstream river basin are taken as given. Starting point is the landscape ecological basis of the river, defining the characteristic (hydro‐morphological) processes and geomorphological/geological structures in each stretch of the river and floodplain area. An in‐depth characterization of these structures and processes helps design floodplains that can accommodate the various river management and development objectives. Often economically strong functions, like flood protection, can be partnered with weaker ones, such as ecosystem restoration. To safeguard spatial quality and sustainability in these integrated projects, the governance aspect is essential. Therefore the Smart Rivers approach addresses both substantial aspects (the “DNA of the River”) as well as procedural and governance elements (called the “Quality Relay”). The principles of the approach are applicable to project design along regulated rivers in densely populated areas all over the world.This article is categorized under: Water and Life > Conservation, Management, and Awareness

A Prospective Study for the Mitigation of the Climate Change Effects: The Case of the North Aegean Region of Greece

One of the biggest challenges of our time is climate change. Every day, at different places of the world, the planet sends alarming messages about the enormous transformations it is experiencing due to human-based activities. The latter are responsible for changing weather patterns that threaten food production, energy production and energy consumption, the desertification of land, the displacement of people and animals because of food and water shortages due to the reductions in rainfall, natural disasters and rising sea levels. The effects of climate change affect us all, and if drastic measures are not considered in a timely manner, it will be more difficult and costly to adapt to the aforementioned effects in the future. Considering this context, the aim of this work is to implement a prospective study/structural analysis to the identified sectors of a regional plan of adaptation to climate change so as to promote the resilience of the region against the negative phenomena generated by the climate crisis. This was achieved in two steps: first, we identified the relationships between the strategic sectors of the plan and organized them in order of importance. Second, we assessed the effectiveness of several public policies oriented towards a city’s resilience according to their impact upon the strategic sectors of the plan and the co-benefits generated by their implementation for society. The results highlight that the most essential sectors for the mitigation of climate change are flood risk management, built environment, forest ecosystem management, human health, tourism and rise in sea level. As a consequence, the most important measures for the resilience of the North Aegean Region against climate change are the ones related to the preparation of strategic master plans for flood protection projects.

The implementation of spatial management as a factor supporting flood protection

This publication presents the issues related to cadastre and real estate management in flood protection. Cadastral data supported by other additional data is the basis for taking action in situations of natural hazards. A real estate cadastre is an important element in the implementation of a real estate acquisition plan. It allows for preliminary assessment of the negative impact of the project, change of the concept and, as a result, expropriation and compensation regulation. In parallel with the activities related to the acquisition of real estate, it is possible to regulate the legal status of other properties. In this publication, the analysis is based on the document entitled "Plan of obtaining real estate and resettlement for the Flood Protection Project in the Odra and Vistula basin, Component 3B: Protection against Sandomierz flood and Tarnobrzeg, Contract 3B.3, flood protection Tarnobrzeg - stage 1 (Wisła 1) ". This area is the research material of actions changing the forms of land management in order to increase the safety of areas exposed to floods. The effects of carrying out this project were an important part of the work, including restrictions in the use, loss of real estate. The implementation of a flood protection project may have a negative impact on the economic status of people living in the areas where the activities were planned. These may be restrictions on the use of real estate, in particular the loss of a part or the whole of the property as a result of expropriation. Ultimately, such actions may result in the resettlement of residents. As a part of the study, the compensation for particular entities was described in detail. The results of surveys confirming the lack of a negative impact on the economic situation of people affected by the project implementation were presented.

Water Treatment Plant Flood Protection Project Boosts Resilience

Water Treatment Plant Flood Protection Project Boosts Resilience

What lies beneath? A decade of underground construction in Hong Kong

Over the past decade Hong Kong has seen a rapid expansion in the use of underground space for Civil Engineering infrastructure projects (Fig. 1). Forty-eight kilometres of rail tunnel has been or is in the process of being constructed with associated shafts (Fig. 2) for access and ventilation and mined caverns for stations (Fig. 3). The catalyst for this expansion may be due to the integration of the Hong Kong Special Administrative Region with China, which commenced in 1997 (with the handing back of Hong Kong and the New Territories to China) and has accelerated over the last decade in line with the global aspirations of China. This integration has been the catalyst for three new major road border-crossing projects (Deep Bay Link; Hong Kong to Macau Bridge; and Liantang/Heung Yuen Wai crossing) and connection into the mainland express rail link (Hong Kong High Speed Rail Project) (Fig. 1). The population has also risen over this period from c. 6.9 million in 2005 to c. 7.3 million in 2016 (tradingeconomics 2016) fueling, in part, the expansion of mass transit rail systems: the Kowloon Southern Link (3 km – complete); the West Island Line (3 km – complete); Sha Tin to Central Link (17 km – under construction); the South Island Line East (7 km – under construction); the Kwun Tong Line extension (3 km – under construction) and the Hong Kong Express Rail Link (26 km – under construction) (Fig. 1). Pressure on valuable land resources has seen the emergence of the innovative use of underground space for: explosives magazines; sewage treatment systems; service reservoirs (Fig. 4); urban drainage and flood protection projects (Fig. 5); and new road networks, such as the Central–Wan Chai Bypass (Fig. 6). Fig. 1. Simplified outline map of the Hong Kong SAR showing the location of the projects referred to in this …

Rawcliffe Bridge flood defence improvements scheme

The £1·6 million Rawcliffe Bridge project forms part of the Environment Agency’s Flood Protection Project between the Aire and Calder Canal and the Dutch River in Yorkshire. The unique Trenchmix system has been successfully used to construct a 2·2-km-long and 3- to 6·5-m-deep low permeability cut-off barrier as part of the flood defence upgrade works. Atkins identified the potential for this technique at the site with Bachy Soletanche Limited joining the project team to offer specialist design and construction expertise for the Trenchmix solution. This collaborative approach helped to refine the specification and optimise the design, which ensured that the complex ground conditions and hydrogeological risks were managed effectively. This paper describes the Trenchmix process and presents the key components of the scheme: understanding the geology of the site and the complex ground and groundwater conditions; selection of an appropriate solution to address the risk of uplift and piping failure; the binder dosage trials in order to determine the cementitious contents required to achieve the required permeability and strength; and the quality assurance testing required to demonstrate compliance with the end-product specification.

Flash flood mitigation modeling — case study small Carpathians

Flash floods are becoming a phenomenon that troubles people more and more often in many Slovak under-mountain regions and society needs to deal with these extreme natural events. This article is showing an example of mathematical modeling of flood protection measures in Small Carpathians region. To secure flood protection, detention reservoirs have been proposed, because of their automatic function that is important due to rapid progress of flash floods. As a base for this project a previous work that attempted to reconstruct the flood has been used. HEC-RAS 4.1.0 software package was used for numerical modeling, which includes flood mitigation calculation. Six variants of proposed detention reservoirs were created and checked by a design flood wave that was created according to rainfall with recurrence period of 100 years. All of the proposed detention reservoirs have exact proportions needed to secure flood protection including height of the dam, length of the dam in crest, type and dimension of outlet and dimensions of emergency spillways. The modeling included flood wave passing during several situations - normal function of detention reservoirs, blocked outlet and dam break. This study should be considered as a base for future flood protection project. An extensive terrain survey has been performed in frame of this project.

Climatic and Environmental Changes Affecting Communities in Atlantic Canada

Small rural coastal communities located in Atlantic Canada are vulnerable to the effects of climate and environmental changes. Major storms have impounded the coastline, causing much physical damage and affecting the socioeconomics of these communities that are composed of an aging population. The current study relays findings based on interviews completed in 2011–2012, following the 2010 winter storms in Atlantic Canada. It portrays the physical and social–ecological impacts affecting 10 coastal communities located in the provinces of Québec, New Brunswick, and Prince Edward Island. Semi-structured interviews held in these provinces are the basis for the contributions of this research. The findings reveal physical changes related to coastal erosion from high-wave impacts and storm surge causing flooding of the coastal zone. Also considered are strategies preferred and actually implemented by residents, such as building of protection walls, although undesirable. Due to funding constraints, however, many of these large-scale flood protection projects are not possible without governmental support. Instead, it is suggested that development be controlled and some respondents in this study upheld that relocation be used to alleviate the situation. Finally, more work is required to improve emergency planning. Better concerted short- and long-term responses need to be coordinated by local authorities and higher up in the government in order to ensure the sustainability of these coastal communities.

Hazard Degrees Assessment of Flash Floods, Applying Multi-Criteria Analysis, Gulf of Aqaba Basins, Sinai, Egypt

Flash flood disasters have a significant impact and cause immense damages to lives and infrastructure. This study will assess the risk of flash floods in Gulf of Aqaba Basins (GAB), Sinai Peninsula. Watershed Modeling System (WMS) package was used to automatically delineate the drainage network and determine the hydro-morphological parameters of 33 GAB sub basins via the 90 m Digital Elevation Model files. These data were statistically analyzed applying Multi Criteria Analysis (MCA) technique to create flash flood hazard scale with and without outliers. Based on the resulted hazard scale MCA technique, it was found that 4% of the studied basins with high hazard degree (class five) while moderately high hazardous basins (class four) represent 32%. Class three contained 29% of the studied basins (moderate hazardous). While the moderately low hazardous basins (class two) contained 18% and the rest belongs to low hazardous degree. It is highly recommended to put into consideration this scale before investing in any flash flood protection projects in the study area.

Greening flood protection through knowledge processes: lessons from the Markermeer dikes project in the Netherlands

Greening flood protection (GFP) is increasingly recognized as an adaptive and flexible approach to water management that is well suited to addressing uncertain futures associated with climate change. In the last decade, GFP knowledge and policies have developed rapidly, but implementation has been less successful and has run into numerous barriers. In this paper, we address the challenge of realizing green flood protection goals by specifically considering knowledge in the decision-making of a Dutch flood protection project in Lake Markermeer. In this project, an ecological knowledge arrangement and a traditional flood protection knowledge arrangement are compared and their interactions analysed. The analysis provides insight into the specific difficulties of implementing GFP measures and identifies ways to realize GFP goals. The primary challenge is twofold: First, a self-reinforcing cycle of knowledge production and decision-making in the flood protection domain inhibits the introduction of innovative and multifunctional approaches such as GFP; second, the distribution of power is severely unbalanced in terms of ecological enhancement and flood protection, favouring the latter. Implementation of GFP requires structural change and the integration of ecological and flood protection knowledge and policy. Potentially rewarding routes towards this integration are the exploration of shared interests in GFP and the creation of mutual dependency between knowledge arrangements. The case study and the insights it provides show that GFP is far from mainstream practice and that implementation requires serious effort and courage to break with historical practices.

Regional flood frequency analysis: comparison of L-moment and conventional approaches for an Indian catchment

A realistic estimation of flood magnitude for a given return period is essential for successful operation and economical design of pivotal hydraulic structures such as dams, reservoirs and spillways, bridges, small culverts, urban drainage systems, flood plain zoning, economic evaluation of flood protection projects, etc. The flood frequency analysis is generally used for flood estimation, entirely based on the assumption that the floods are random and the floods in future are supposed to bear similar statistical properties that have occurred in the past. If adequate data are available at-site flood frequency analysis is used, otherwise regional flood frequency analysis (RFFA) is preferred for flood estimation. The RFFA for various small and medium catchments of India with different approaches have been carried out and reported in the literature. The focus of the present study is to carry out the RFFA using different approaches i.e. conventional method and L-moment and comparing the results for the Krishna and Penner subzone 3(h) of India. It was found that the values of growth factors obtained by the conventional method are higher than those of L-moment methods, thus leading to conservative estimate of the peak floods.