Colin R. Thorne

University of Nottingham | Notts · School of Geography

Lateral connectivity between rivers and terrestrial landscapes is critical for both river and landscape health. Due to widespread anthropogenic degradation of riverscapes, river management is aiming to connect rivers to floodplains, riparian zones, and wetlands, putting a spotlight on lateral connectivity. However, there is currently no consensus o...

Stream restoration is a proposed climate adaptation tool; however, outcomes of floodplain restoration on stream temperature have been debated. Despite a growing number of studies that investigated water temperature in restored streams, few have quantified temperature variations in new habitat types created by restored hydrogeomorphic processes to e...

River channels, riparian and floodplain forms and dynamics are all influenced strongly by biological processes. However, the influence of macroinvertebrates on entrainment and transport of river sediments remains poorly understood. We use an energy‐based approach to explore the capacity of benthic animals to move surficial, gravel‐bed particles in...

Blue-Green Cities manage flood risk by recreating more naturally oriented water cycles in urban areas through the restoration of natural drainage channels, reduction in impervious surfaces and implementation of Blue-Green Infrastructure (BGI - for example, swales, wetlands, green roofs) to enhance infiltration, attenuation and surface storage of wa...

Streams systems draining upland landscapes provide valuable ecosystem services, but they are vulnerable to incision and channelization caused by anthropogenic disturbance. Restoring a degraded stream to its pre‐disturbance condition by reconnecting the channel to its historical floodplain aims to recover lost hydro‐morphological processes and funct...

Improvements in simulating and communicating the evolutionary trajectory of river morphology in response to environmental forcing over multi‐decadal timeframes would foreshadow the development of “foresight competency” in river management, whereby resource managers could strategically plan toward the most preferred of several plausible futures. Of...

Catchment floods are more challenging due to intensive urbanization and climate change. Enlightened by the Low Impact Development (LID), China initiated the Sponge City Program (SCP) to transform Urban Flood Management (UFM) to be more environmentally friendly in 2013. The China National Government (CNG) has subsidized municipal SCP facilities to e...

This manual provides information for understanding, assessing, and addressing interactions between river functions and transportation infrastructure. The manual adopts a holistic approach by illustrating not only the effects of rivers on roads and bridges, but also the effects of roads and bridges on rivers and their floodplains. Recognizing these...

Flooding of the town of Forres, Scotland prompted the implementation of a flood alleviation scheme (FAS) featuring a low earth‐fill dam constructed upstream of the town to create a flood retention area, limiting peak discharges entering the urban area. Flow through the dam is controlled by a weir, and it was recognised that if coarse sediment, larg...

A maturing body of evidence suggests that anthropogenic impacts on river-wetland corridors (RWCs) are greater and more widespread than previously recognized. Partly, this stems from the difficulty of differentiating between legacy anthropogenic impacts and channel evolution resulting from natural disturbances. Here, we apply the geomorphic grade li...

Background Historically, wildfire regimes produced important landscape‐scale disturbances in many regions globally. The “pyrodiversity begets biodiversity” hypothesis suggests that wildfires that generate temporally and spatially heterogeneous mosaics of wildfire severity and post‐burn recovery enhance biodiversity at landscape scales. However, riv...

The channel of the Lower Mississippi River is primarily the product of natural flows acting on the floodplain materials over centuries and millennia to form an alluvial stream. Channel geometry analysis is possible for the Lower Mississippi River thanks to the existence of historical, comprehensive, and annual hydrographic surveys of the river. Dur...

A maturing body of evidence suggests that anthropogenic impacts on river-wetland corridors may be greater and more widespread than previously recognized. We applied the Geomorphic Grade Line (GGL) method to define pre-Anthropocene valley surfaces within segments of the 42-kilometer Entiat River Valley (ERV) of the North Cascade Mountains, USA. We d...

Responsibility for flood risk management (FRM) is increasingly being devolved to a wider set of stakeholders, and effective participation by multiple FRM agencies and communities at risk calls for engagement approaches that supplement and make the best possible use of hydrologic and hydraulic flood modelling. Stakeholder engagement must strike a co...

Urban flooding is a key global challenge which is expected to become exacerbated under global change due to more intense rainfall and flashier runoff regimes over increasingly urban landscapes. Consequently, many cities are rethinking their approach to flood risk management by using green infrastructure (GI) solutions to reverse the legacy of hard...

River-wetland corridors form where a high degree of connectivity between the surface (rheic) and subsurface (hyporheic) components of streamflow creates an interconnected system of channels, wetlands, ponds, and lakes. River-wetland corridors occur where the valley floor is sufficiently wide to accommodate a laterally unconfined river planform that...

Rapid urbanization has sharply increased the pressure of urban water issues (e.g., urban flooding and water pollution) in the Chinese megacities during last three decades. Sustainable urban water management approaches, such as Nature Based Solutions (NBS) and Low Impact Developments (LIDs), have successfully delivered long-term benefits to cities i...

In the original article, there was a mistake in the legend for [...]

Growing urban populations, changes in rainfall patterns and ageing infrastructure represent significant challenges for urban water management (UWM). There is a critical need for research into how cities should adapt to become resilient to these impacts under uncertain futures. UWM challenges in the Ebbsfleet Garden City (UK) were investigated via a...

• Anthropogenic litter (solid manufactured waste) is an understudied but pervasive element of river systems worldwide. Its physical structure generally differs from natural substrates, such as gravel and cobbles (hereafter rocks). Consequently, anthropogenic litter could influence ecological communities in urban rivers by providing novel habitats....

Urban flooding has become a serious issue in most Chinese cities due to rapid urbanization and extreme weather, as evidenced by severe events in Beijing (2012), Ningbo (2013), Guangzhou (2015), Wuhan (2016), Shenzhen (2019), and Chongqing (2020). The Chinese "Sponge City Program" (SCP), initiated in 2013 and adopted by 30 pilot cities, is developin...

A primary goal of river restoration is to reestablish lost ecological functions. Yet the impact of restoration on diatom assemblages and algal biomass in a stream is rarely addressed in the scientific literature reporting the outcomes of restoration projects aimed at improving riverine habitat. To investigate the potential for using benthic diatoms...

Blue‐Green Infrastructure (BGI) is recognized as a viable strategy to manage stormwater and flood risk, and its multifunctionality may further enrich society through the provision of multiple cobenefits that extend far beyond the hydrosphere. Portland, Oregon, is an internationally renowned leader in the implementation of BGI and showcases many bes...

Blue-Green Infrastructure (BGI) ponds have an important function of alleviating flood risk and provide water quality improvements among other multiple benefits. Characterisation of sediments and suspended particulate matter (SPM) is understudied, but is indispensable for assessing the ponds' functioning because of their role in biogeochemical cycli...

Managing urban flood risk is a key global challenge of the twenty-first century. Drivers of future UK flood risk were identified and assessed by the Flood Foresight project in 2002–2004 and 2008; envisaging flood risk during the 2050s and 2080s under a range of scenarios for climate change and socio-economic development. This paper qualitatively re...

Achieving urban flood resilience (UFR) at local, regional and national levels requires a transformative change in planning, design and implementation of urban water systems. Flood risk, wastewater and stormwater management should be re-envisaged and transformed to: ensure satisfactory service delivery under flood, normal and drought conditions, and...

River management based solely on physical science has proven to be unsustainable and unsuccessful, evidenced by the fact that the problems this approach intended to solve (e.g., flood hazards, water scarcity, and channel instability) have not been solved and long‐term deterioration in river environments has reduced the capacity of rivers to continu...

A 2.5‐km³ debris avalanche during the 1980 eruption of Mount St. Helens buried upper North Fork Toutle River valley and reset the fluvial landscape. Since then, a new drainage network has evolved. Cross‐sectional surveys repeated over nearly 40 years at 16 locations along a 20‐km reach of river valley document channel evolution. We analyze spatial...

The foundations of river restoration science rest comfortably in the fields of geology, hydrology, and engineering, and yet, the impetus for many, if not most, stream restoration projects is biological recovery. Although Lane's stream balance equation from the mid‐1950s captured the dynamic equilibrium between the amount of stream flow, the slope o...

Portland, Oregon, USA, demonstrates many best practice examples of sustainable stormwater management that embrace the Blue‐Green ideal of reconfiguring the urban water cycle to more closely resemble the natural water cycle. For more than a decade, the City of Portland has invested widely in Blue‐Green infrastructure (BGI) to help reduce the number...

Sustainable drainage systems and 'blue-green' infrastructure provide a range of environmental, economic and social benefits in addition to managing water quantity and quality. Recognition of the multi-functionality of these systems and their multiple benefits could lead to joint efforts to deliver infrastructure that meets the strategic objectives...

Surface water flooding is currently viewed as the most serious water-related issue in many of the China’s large cities due to rapid urbanization, land-use change and the process of rapid socio-economic development. In 2014, the People’s Republic of China established the concept of the ‘Sponge City’, which will be used to tackle urban surface-water...

Flood and water management governance may be enhanced through partnership working, intra- and cross-organisational collaborations, and wide stakeholder participation. Nonetheless, barriers associated with ineffective communication, fragmented responsibilities and ‘siloed thinking’ restrict open dialogue and discussion. The Learning and Action Allia...

Thirty-seven years post-eruption, erosion of the debris avalanche at Mount St. Helens continues to supply sediment to the Toutle-Cowlitz River system in quantities that have the potential to lower the Level of Protection (LoP) against flooding unacceptably, making this one of the most protracted gravel-bed river disasters to date. The Portland Dist...

Flooding is a very costly natural hazard in the UK and is expected to increase further under future climate change scenarios. Flood defences are commonly deployed to protect communities and property from flooding, but in recent years flood management policy has looked towards solutions that seek to mitigate flood risk at flood-prone sites through t...

Sustainable Drainage Systems (SuDS) and Blue-Green infrastructure (BGI) provide a range of environmental, economic and social benefits in addition to managing water quantity and quality. Recognition of the multifunctionality of SuDS and BGI, and the specific benefits that may accrue to different beneficiaries, may facilitate partnership working tow...

In this study, a recently revised version of the channel evolution model, named the Stream Evolution Model (SEM), was applied to the upper North Fork Toutle River disrupted by the deposition of a 2.5-km3 debris avalanche during the catastrophic eruption of Mount St. Helens in 1980. The results show that, in the first few years following the eruptio...

This paper examines the feasibility of a basin‐scale scheme for characterising and quantifying river reaches in terms of their geomorphological stability status and potential for morphological adjustment based on auditing stream energy. A River Energy Audit Scheme (REAS) is explored, which involves integrating stream power with flow duration to inv...

There is a recognised need for a fundamental change in how the UK manages urban water and flood risk in response to increasingly frequent rainfall events coupled with planned urban expansion. Approaches centred on ‘living with and making space for water’ are increasingly adopted internationally. Nonetheless, widespread implementation of Blue-Green...

The evolution of the Yellow River delta is characterized by heavy sediment load, rapid seaward migration, frequent avulsions, and intense anthropogenic disturbances. Evolution of the delta channel following avulsions is very complex and has not yet been thoroughly understood. In the research presented by this paper, we conducted comprehensive analy...

Advancing stakeholder participation beyond consultation offers a range of benefits for local flood risk management, particularly as responsibilities are increasingly devolved to local levels. This paper details the design and implementation of a participatory approach to identify intervention options for managing local flood risk. Within this appro...

A Blue-Green City aims to recreate a naturally-oriented water cycle while contributing to the amenity of the city by bringing water management and green infrastructure together. The Blue-Green approach is more than a stormwater management strategy aimed at improving water quality and providing flood risk benefits. It can also provide important ecos...

Blue-Green Infrastructure (BGI) and Sustainable Drainage Systems (SuDS) are increasingly recognised as vital components of urban flood risk management. However, uncertainty regarding their hydrologic performance and lack of confidence concerning their public acceptability create concerns and challenges that limit their widespread adoption. This pap...

River channel sediment dynamics are important in integrated catchment management because changes in channel morphology resulting from sediment transfer have important implications for many river functions. However, application of existing approaches that account for catchment‐scale sediment dynamics has been limited, largely due to the difficulty i...

The Sanmenxia Dam built in 1960 in the middle reach of the Yellow River has experienced severe sedimentation problems, not only in the reservoir area itself but also extending hundreds of kilometers in the backwater region. Morphological responses in the middle Yellow River and its tributary, the Wei River, upstream of the dam have generally lagged...

Between December 2013 and February 2014, an extreme storm surge, a series of intense storms, and the cumulative effects of heavy and persistent rainfall caused widespread flooding throughout the UK, prompting renewed public and scientific debates on who, or what, might be to blame. The public divided fairly evenly into two diametrically opposed gro...

In the UK a research consortium has been funded to develop new strategies for managing urban flood risk as part of wider, integrated urban planning intended to achieve environmental enhancement and urban renewal in which multiple benefits of Blue-Green Cities are rigorously evaluated and understood. This approach is very much part of the resilience...

A Blue-Green City aims to recreate a naturally-oriented water cycle while contributing to the amenity of the city by bringing water management and green infrastructure together. The Blue-Green approach is more than a stormwater management strategy aimed at improving water quality and providing flood risk benefits. It can also provide important ecos...

Extensive new pipeline systems proposed to transport natural gas and oil throughout North America will potentially result in thousands of new stream crossings. The watercourses encountered at these crossings will range from small, ephemeral headwater streams to large, perennial mainstem rivers; from dynamic gravel-bed streams to stable bedrock chan...

The ‘project risk screening matrix’ derives from a broader effort to assist US government agency staff in reviewing proposed stream management and restoration projects more efficiently and effectively. The River Restoration Analysis Tool (RiverRAT) developed through this effort provides a thorough, comprehensive and auditable approach to review and...

For decades, Channel Evolution Models have provided useful templates for understanding morphological responses to disturbance associated with lowering base level, channelization or alterations to the flow and/or sediment regimes. In this paper, two well‐established Channel Evolution Models are revisited and updated in light of recent research and p...

The US Army Corps of Engineers has constructed numerous river engineering structures in and along the Middle Mississippi River. River training and bank stabilization measures include pile dikes, stone dikes, bendway weirs, chevrons, and revetments. Concerns have long been voiced about the effects of these structures on flood stages. Recent debate c...

The Jamuna River is the downstream continuation of the Brahmaputra in Bangladesh. It is one of the largest sandbed braided rivers in the world and every year it erodes thousand hectares of mainland floodplain, rendering tens of thousands of people landless and/or homeless. Understanding the morpho- dynamics of this river and its responses to the va...

The assessment of flood risk is now widely recognised to need research and data on both the probability and the consequences of flooding; the research reported here concentrates on the latter data input. Building on the UK Foresight Future Flooding project, this paper describes the development of future scenarios through which to assess possible fu...

The Taihu Basin, situated on the south side of the Yangtze delta, is a large flood-prone area that has urbanised rapidly. The risk of flooding is set to increase in future because of continued economic development and the impacts of climate change. Scenario analysis has been adopted to help understand the potential impacts of long-term change on fl...

In this study continuous wavelet transforms are used to explore spatio-temporal patterns of multi-scale bank line retreat along a 204 km reach of the Jamuna River, Bangladesh. A sequence of eight bank line retreat series, derived from remotely-sensed imagery for the period 1987–1999, is transformed using the Morlet mother wavelet. Bank erosion is s...

Spatial and temporal variation in river bank erosion rates in a British upland catchment was quantified over a 2 year period using a network of erosion pins. Potential causal mechanisms and site-specific controls of this erosion were examined through bivariate analyses and significance testing. Problems with existing process-inference methodologies...

The river reach is a pervasive term within contemporary river research and applications. Yet, despite its prevalence, there is a notable lack of consistency in its definition. This paper identifies the presence of two broad types of reach definition within the academic literature, operational and functional, and argues that a functional definition...

A general framework for modelling morphological responses to perturbation is proposed, based on the underpinning principle that the rates of morphological response in alluvial channels are initially high and then decrease through time as the system relaxes following disturbance. The framework includes three morphological response models, each devel...