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This study aims to provide a review for scour in complex rivers and streams with coarser bed material, steep longitudinal bed slopes and dynamic environments, in the interest of the safety and the economy of hydraulic structures. The knowledge of scour in such geographical complexities is very crucial for a comprehensive understanding of scour failures and for establishing definitive criteria to bridge this major research gap.

The existing available literature shows significant work done in case of silt, sand and small sized coarser bed material but any substantial work for bed material of gravel size or above is lacking, resulting in a wide gap. Though some researchers have attempted to explore possibilities of refining the existing models by adding pier size, shape, sediment non-uniformity and armouring effects, which otherwise have been given a miss by the various researchers, including the pioneer in the field Lacey–Inglis (1930). But still, a rational model for scour estimation in such complex conditions for global use is yet to come. This is because all the parameters governing the scour have not been studied properly till date as is evident from the globally available literature and is witnessed in the field too, in recurrent failure of hydraulic structures especially bridges.

The researchers presume that the finer materials move only as a result of erosion. However, in actual field conditions, it has been observed that the large-sized stones also roll down and cause huge erosion along the river bed and damage the hydraulic structures, especially in the steep river/stream beds along hilly slopes. This fact has been overlooked in the models available globally and has been highlighted only in the current work in an attempt to recognize this major research gap. A study carried out on a number of streams globally and in Jammu and Kashmir, India also, has shown that in steep river and stream beds with bed material consisting of gravel size or greater than gravel, large scour holes ranging from 1 m to 5 m were created by furious floods, and due to other unknown forces along the channel path and near foundations of hydraulic structures.

To the best of the authors’ knowledge, this work is purely original.

This is a modified version of the 2022 George Herbert Mead Lecture that I delivered at the Annual Meeting of the National Communications Association in New Orleans, LA. Drawing upon ethnographic research with Mississippi River pilots, I outline the strengths and weaknesses of Mead's conceptualization of “mind” as a means to develop the “great cooperative community” he envisioned. I argue that although we possess the cognitive capacity to take the attitude of a multitude of others, even during complex and evolving scenarios, there are also material incentives for some groups to impede the emergence of the mind via the construction of “closed-networks.” I identify one example of a closed-network – professional associations – to demonstrate how and why they attempt to prevent outsiders from role-taking with members of their group. Although the persistence of closed networks hampers Mead's vision of a more co-operative society, it is only by understanding the origins of such barriers to mind that we can address the root causes of their construction.

This article aims to show how communities with severe river flooding can develop sustainable flood plans that remediate environmental problems caused by previous river straightening and other structural flood controls.

The article builds on a case study of the nationally recognized Napa River Flood Protection Project (USA), which incorporates an ecological living river strategy and builds on strong community participation to restore a river and its floodplain. After discussing the drawbacks of structural flood control measures, and especially of river straightening, reviews the contents of the Napa Flood Project and the public participation process necessary for its design, approval and implementation.

The key lessons learned from Napa's flood project are that: undoing past structural works is difficult but feasible; ecological criteria can and should be used to design modern flood projects; involvement of a wide and diverse group of stakeholders is crucial to developing and implementing an environmentally sustainable flood management project; and the US Army Corps of Engineers can work with communities and depart from its typical, structural flood control approaches.

Information on straightened rivers is extremely limited. Furthermore, this study focuses on flood planning for US rivers, and may therefore be less useful elsewhere in the world where the frequency of river straightening may differ.

This case study provides a critique on river straightening, which is a poorly documented but fairly frequent approach to flood control. This article helps to fill gaps in the knowledge of how communities can, and are, addressing environmental concerns associated with flood controls and river straightening.

The Indus, Mekong, and Ganges River deltas, which have created one of the world’s largest delta and submarine fan system, currently contribute a major fraction of freshwater to East and South Asia. All these deltas are those regions in the world that face major challenges in their water sector due to population growth, urbanization, industrialization, sea-level rise, and salinity intrusion into inland and water bodies, all aggravated by climate change. Among them, salinity intrusion is currently one of the key issues that directly and indirectly cause water insecurity in East and South Asia, which ultimately hamper livelihood, agricultural production, and social interference. Hence, this chapter gives a comprehensive description on the nature and extent of the salinity problem, its adverse effects on livelihood and water sector, and then the focus goes to current and future sustainable water resource management within the delta to finally move on to conclusion and suggestions.

Governor Robert F. Casey made his first state visit to Homestead, Pennsylvania the day after his inauguration in January 1987 to announce a package of plans for restoring economic vitality to metropolitan Pittsburgh in the wake of steel's collapse. Earlier urban renewal had involved large-scale demolition of older downtowns for conversion to commercial and industrial use, but state and local officials now emphasized a two-pronged redevelopment approach largely modeled on the success of the postwar suburbs. The closure of the Monongahela River (Mon) Valley's mammoth steel mills opened large swaths of land and prompted calls for planned riverfront manufacturing and retail districts similar to those sites sprouting up at suburban interchanges. A second and related effort involved schemes to build new highways tying aging communities in the river valleys to both Pittsburgh and new suburban growth areas, such as the sprawling “edge city” of Monroeville less than 10miles away. Indeed, Casey had a special project in mind for revitalizing the iconic Homestead – construction of the long-delayed Mon/Fayette Expressway that would parallel the river south of Pittsburgh. “This is another big step [to] help bring businesses and jobs into the region,” the governor later declared. “No longer is this valley a forgotten valley” (as cited in Basescu, 1989, p. 1).

The paper introduces a lesser-known cultural landscape along the sacred Bhagirathi-Hooghly river in the Indian city of Kolkata, with particular reference to its built and natural heritage. The narratives cover the cultural and ecological qualities of the unique “ghat-scape” (riverfront pavilions with steps descending into the river) and their contemporary urban challenges. It also explores the suitability of the Historic Cultural Landscape (HCL) tools, or their adapted versions, in managing this exceptional landscape.

The paper is structured under six discrete sections covering the inventory and assessment, interpretation and evaluation and possible roadmap for the ecological restoration of the riverfront cultural landscape. Primary and secondary studies were conducted to understand the related challenges and opportunities. The authors then examined the application of the HCL tools based on a conceptual framework and identified the alternative approaches suitable for its restoration. Finally, a successfully restored ghat environ is taken as a model and reviewed against the most potent approach in addressing the eco-cultural criticalities.

The paper argues in favour of a paradigm shift from riverfront “development” to riverfront “restoration” with particular emphasis on the ghat-architecture. Three eco-cultural restoration alternatives were derived out of the HCL principles. A practical case study found that a community-led approach positively influences restorative actions, cultural heritage management and long-term sustainability.

The HCL tools comprising planning, regulatory systems, financial designs and community engagement have been explored for the first time in the context of the unique riverfront “ghatscape” of Kolkata. An under-discussed topic, it has been brought to the centre stage to gain new insights into the Indian cultural landscape heritage. An HCL-based new approach in their management came forth through a review of a successful case study.

This study aims to assess how small check dams built across rivers in India’s drylands can revitalize rivers during dry season and mitigate local climate change consequences. The surface- and groundwater resources are increasingly under pressure throughout India. The imminent climate change consequences will further aggravate the crisis and this paper has addressed this difficult issue.

This study was conducted in India’s dryland districts, namely, Dahod in Gujarat and Jhalawar and Banswara in Rajasthan state, to assess the impacts of small dams. Data on dams, sustainability, groundwater levels and benefits to farmers were systematically collected to analyze advantages offered by check dams with reference to climate change mitigation.

The study shows that 356 check dams built during 1990-2012 across the tribal drylands of India, with a cost of USD 17 million, benefited over one million people from farming communities. The dams also increased groundwater levels in villages, revived rivers during dry season and increased forest growth along rivers, ultimately mitigating local climate change-imposed negative consequences.

Data on small dams are limited in India, as public have no access to such data because the work is done mainly by local contractors.

The check dams, the role of which is highlighted here, are simple, eco-friendly and cost-effective. If it is adopted across the vast drylands of India and elsewhere, it has the potential to increase agricultural output; guarantee food security; enhance groundwater resources; and, above all, mitigate local climate change consequences.

If check dams are built in large numbers across India, it has the potential to increase agricultural output; guarantee food security; enhance groundwater resources; and, above all, mitigate climate change.

The highlighted results and discussion will guide scientists, politicians and policymakers to make informed decisions to combat India

s future climate change consequences.

Rivers flowing through the land are a source of life. They have different importance and functions such as for drinking, sailing, irrigating crops, generating electricity, sightseeing, fishing, and so on. In addition, animals like amphibians, birds, and mammals also live and propagate near the river environment. Therefore, rivers are ecosystems for some animals and plants that are special, rare, or on the brink of extinction (Water Resources Agency, Ministry of Economic Affairs, 2006).