River Meanders--theory of Minimum Variance

River Meanders--theory of Minimum Variance
Author: Walter Basil Langbein
Publisher:
Total Pages: 24
Release: 1966
Genre: Hydrology
ISBN:

The geometry of a meander is that of a random walk whose most frequent form minimizes the sum of the squares of the changes in direction in each unit length. Changes in direction closely approximate a sine function of channel distance. Depth, velocity, and slope are adjusted so as to decrease the variance of shear and the friction factor in a meander over that in an otherwise comparable straight reach of the same river.

Theoretical Morphodynamics: River Meandering

Theoretical Morphodynamics: River Meandering
Author: Giovanni Seminara
Publisher: Firenze University Press
Total Pages: 260
Release: 2024-04-05
Genre: Technology & Engineering
ISBN:

This monograph discusses the mechanics of Meandering Rivers with the help of the mathematical and modeling tools built up in the previous monograph of the same Authors (monograph 1 of the present series). After introducing the reader to the ubiquitous character of meandering streams, we discuss the hydrodynamics of curved channels with fixed beds and banks. Next, we extend the analysis to account for the mobile character of the bed and show that it gives rise to the alternate sequence of riffles and pools that characterize river meanders. Allowing for the erodible character of the river banks then allows to build up a rational theory of meander formation able to explain most of the features observed in nature: meander growth, migration, skewing, multiple loops, cutoffs and meander belts.

River Mechanics

River Mechanics
Author: Pierre Y. Julien
Publisher: Cambridge University Press
Total Pages: 460
Release: 2002-08-19
Genre: Science
ISBN: 9780521529709

This textbook offers a thorough analysis of rivers from upland areas to oceans. It scrutinizes select methods underlining both theory and engineering applications, emphasizing the mechanics of flood wave propagation and sediment transport in rivers. The text covers fundamental principles, engineering analysis, and engineering design, with problems, examples, and case studies throughout. Channel stability and river dynamics are examined in terms of river morphology, lateral migration, aggradation, and degradation. Detailed treatments of riverbank stabilization and engineering methods are provided, while separate chapters cover physical and mathematical models. This essential text presents both the theory and design of measures to reduce flood impact and bank erosion, to improve navigation, and to increase water supply to cities and irrigation canals. Over 100 exercises and nearly twenty case studies make this book an invaluable learning tool for students, and researchers and practitioners will find it a concise resource on the mechanics of rivers.

A Systems Approach for River and River Basin Restoration

A Systems Approach for River and River Basin Restoration
Author: Theodore Endreny
Publisher: MDPI
Total Pages: 204
Release: 2021-05-27
Genre: Technology & Engineering
ISBN: 3039436317

Communities increasingly find that the water quality, water levels, or some other resource indicator in their river basins do not meet their expectations. This discrepancy between the desired and actual state of the resource leads to efforts in river basin restoration. River basins are complex systems, and too often, restoration efforts are ineffective due to a lack of understanding of the purpose of the system, defined by the system structure and function. The river basin structure includes stocks (e.g., water level or quality), inflows (e.g., precipitation or fertilization), outflows (e.g., evaporation or runoff), and positive and negative feedback loops with delays in responsiveness, all of which function to change or stabilize the state of the system (e.g., the stock of interest, such as water level or quality). External drivers on this structure, together with goals and rules, contribute to how a river basin functions. This book reviews several new research projects to identify and rank the twelve most effective leverage points to address discrepancies between the desired and actual state of the river basin system. This book demonstrates that river basin restoration is most likely to succeed when we change paradigms rather than try to change the system elements, as the paradigm will establish the system goals, structure, rules, delays, and parameters.

River and Coastal Engineering

River and Coastal Engineering
Author: Ramakar Jha
Publisher: Springer Nature
Total Pages: 408
Release: 2022-08-03
Genre: Science
ISBN: 3031050576

This book deals with important topics of current interest, such as climate change, floods, drought, and hydrological extremes. The impact of climate change on water resources is drawing worldwide attention in these days; water resources in many countries are already stressed and climate change along with burgeoning population, rising standard of living, and increasing demand are adding to the stress. Further, river basins are becoming less resilient to climatic vagaries. Fundamental to addressing these issues is hydrological modelling which is covered in these books. Further, integrated water resources management is vital to ensure water and food security. Integral to the management is groundwater and solute transport. The books encompass tools that will be useful to mitigate the adverse consequences of natural disasters. This book is useful for those working in river and coastal engineering. River Engineering is important for fluvial hydraulics, sediment transport, morphometry, desilting, trap efficiency, silting and desilting process. Coastal engineering includes storm surge forecast, optimization of harbour, wave modelling, and shoreline changes.