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Real-Time Operation of Reservoirs during Flood Conditions Using Optimization-Simulation with One- and Two-Dimensional Modeling
Published in Saeid Eslamian, Faezeh Eslamian, Flood Handbook, 2022
Hasan Albo-Salih, Larry W. Mays, Daniel Che
Flooding is the inundation of land downstream of a river and/or reservoir system by the overflow and rise of water level resulting from extreme rainfall, dam breach, or snowmelt, exceeding the capacity of channels of the river system, lake, or the way in which it runs. Figure 13.1 is a schematic of a simple river-reservoir system with reservoir inflows and reservoir releases. The flooding downstream of the reservoir and the flooding within the reservoir are dependent on the reservoir inflow and the reservoir releases. The combined flow of several tributaries can cause even more flooding along rivers and their floodplains. Despite the extensive studies that many previous researchers have performed to analyze the floods and the management of flow, many flooding problems still occur causing tremendous devastation in life and properties in both the short and the long terms. As of late, new approaches and systems created using the GIS techniques, allow more productive storage and processing of information and joint examination of various datasets.
Introduction
Published in Khalid Elnour Ali Hassaballah, Land Degradation in the Dinder and Rahad Basins, 2021
Over the past decades, identification of the adverse consequences of both human and natural impacts on rivers, combined with an increase in overall environmental awareness, guided to many initiatives for river restoration as part of river basin management programs. Some river restoration studies intended to enhance the water quality (Jordan et al., 1990) while others intended to enhance the ecological integrity of river systems (RRP, 1993). No matter what the driving force are, there is a developing scientific knowledge related to theories, methods and effective applications of river ecosystem restoration being applied over the world (e.g. Brookes and Shields, 1996; Connelly and Knuth, 2002; Giller, 2005; Wohl et al., 2005; Kondolf, 2006; Palmer et al., 2010; Bernhardt and Palmer, 2011). The role of streamflow and the river channel morphology in defining the structure of river ecosystems received little consideration until the early 1980s (Newbury, 1984; Nowell and Jumars, 1984). Maddock (1999) emphasized that upcoming studies on the growth of physical habitat assessments must attempt to integrate and combine the wide range of spatiotemporal scales that affect the ecosystem functioning and hence the human wellbeing.
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Published in Reem Fikri Mohamed Osman Digna, Optimizing the Operation of a Multiple Reservoir System in the Eastern Nile Basin Considering Water and Sediment Fluxes, 2021
Reem Fikri Mohamed Osman Digna
A river basin system consists of water source components and in-stream and off-stream demand components (McKinney et al., 1999). In addition to natural and physical processes, the river basin is characterized by development projects and management policies. River system planning and management is usually a multi-objective problem, with many objectives being in conflict (M. Karamouz, Szidarovszky, F.,, 2003). The conflicts in river system planning and management arise when the water demands of different sectors are supplied from one river system and river flow is less than in-stream and off-stream water requirements. Infrastructures such as reservoirs are thus vital to organize and allocate the water for different water users.
A complex balance: assessing perspectives on decommissioning large dams to restore river ecosystems
Published in Water International, 2023
Joshua Matanzima, Teboho Mosuoe-Tsietsi
The restoration of river systems could also mean that the socio-cultural and economic activities – such as religion, riverine cultivation, food from aquatic organisms and transportation – reliant on river ecosystems can be revived. With regards to religion, in some contexts communities attach religious significance to rivers. For instance, in the Kariba case, the Zambezi River, before its damming, was endowed with sacred islands, rapids and pools that were the abode of water spirits which were important to the people’s everyday lives (Matanzima, 2022a). When the river flow was disrupted by the construction of the Kariba Dam, the surrounding communities lost access to the river and, thus, to its religious significance. In terms of transportation, the restoration of a river ecosystem can mean that communities separated by dams may have easier access to each other again. However, despite the positive environmental, financial and public safety impacts that may be associated with the removal of dams, there are also arguments against the decommissioning of dams.
Remote sensing and GIS techniques to monitor morphological changes along the middle-lower Vistula river, Poland
Published in International Journal of River Basin Management, 2021
Fluvial morphology is driven by internal and external factors like water discharge, woody debris and sediment transport, as well as channel, sandbars and islands migration, or floodplain and banks erosion and accretion (see, among many others, Abbe & Montgomery, 2003; Gurnell et al., 2012; Latrubesse et al., 2005). Changes of river geometry and alterations of the channel path can be correlated to natural drivers such as the amount and type of sediments feeding the river system, or the local hydrological regime (Schumm, 1969). Nowadays, the increased anthropic pressure on alluvial rivers worldwide is accelerating these natural processes by changing the liquid and solid inputs in a faster manner, acting both in the channel (dam construction, channel diversion, mining, river engineering works, etc.) and on the hillslopes (e.g. Klimek, 1987; Ortega et al., 2014; Surian & Rinaldi, 2003; Wellmeyer et al., 2005). Ultimately, the relationships between the fluvial hydrological, morphological, biogeochemical and ecological processes results altered (Allen & Pavelsky, 2018). Indeed, in most of the large and intermediate watercourses worldwide, the human presence results predominantly in shaping the environment, generally involving detrimental effects (Kesel, 2003; Nones, 2019; Yao et al., 2011).
System dynamics for water resource sustainability issues: assessing the impact of river restoration plans in the Upper-Middle Ciliwung river basin, Indonesia
Published in International Journal of River Basin Management, 2021
River restoration aims to (1) restore natural river conditions; (2) restore river functions to support biodiversity, recreation, flood management, and landscape development; (3) improve river system resilience; and (4) create a framework for river utilization in a sustainable, multifunctional manner (The River Restoration Centre [RRC], 2011). Some restoration projects have failed because of the gap between the restoration plans and the expected results of a restoration project. Water resource decision makers need to assess the efficiency and effectiveness of restoration plans over a long period of time.