No / This evidence review was commissioned as part of the Joint Research Programme project ‘Working Together to Adapt to a Changing Climate: Flood and Coast’ (2018 to 2021). The project is a response to concerns about the impacts of climate change and the likelihood of significantly higher levels of risk to communities due to increased flooding (including inland) or coastal erosion. It aims to produce new learning about, and enhanced guidance for, community engagement practice in situations where this might be particularly challenging, for example, in situations where there is a low likelihood of building or maintaining flood defences in the medium to long term. / Environment Agency / The publisher requests that no file be uploaded. However, the latest version of the full file is available on the Government website on the link above.

Floodplain inundation often provides water quality benefits by trapping sediment and biogeochemically transforming other pollutants. Hydrologic floodplain connectivity is a measure of water exchanges and interactions between the main channel and the floodplain via surface (inundation) and subsurface (groundwater) connections. Using an automated model combining GIS and numerical analysis software, this study examined floodplain inundation patterns and measured floodplain connectivity for the Mahantango Creek watershed (Pennsylvania, USA). Connectivity was quantified by developing a metric that included inundation area and duration. Long-term hydrographs at each reach in the watershed were developed via QPPQ (Flow-Percentile-Percentile-Flow) methodology using regional regression analysis to calculate the ungauged flow duration curves (FDC). Inundation area (normalized to stream length) was found to increase with drainage area, suggesting larger streams have more area available for biogeochemical activity. Annual connectivity increased with drainage area, suggesting larger streams, having higher connectivity, should be the focus of individual reach restoration projects due to higher potential for water quality benefits. Across the watershed as a whole, however, the total annual connectivity across first order streams was greater than higher order streams, suggesting the collection of small streams in a watershed may have a stronger effect on outlet water quality. Connectivity was consistently higher during the non-growing season, which was attributed to higher flows. Despite higher connectivity during the non-growing season, increased floodplain biological activity may be negated by low temperatures, reducing microbial activity. Correlations between land use and connectivity were also found, emphasizing dynamics between flow, channel morphology, and floodplain inundation. / Master of Science

Restoring hydrologic connectivity between the channel and floodplain is a common practice in stream and river restoration. Floodplain hydrology and hydrogeology impact biogeochemical processing and potential nutrient removal, yet rigorous field evaluations of surface and groundwater flows during overbank floods are rare. We conducted five sets of experimental floods to mimic floodplain reconnection. Experimental floods entailed pumping stream water onto an existing floodplain swale, and were conducted throughout the year to capture seasonal variation. Each set of experimental floods entailed two replicate floods occurring on successive days to test the effect of varying antecedent moisture. Water levels and specific conductivity were measured in surface water, shallow soils, and deep soils, along with surface flow into and out of the floodplain. Total flood water storage increased as vegetation density increased and or antecedent moisture decreased. Hydrologic flow mechanisms were spatially and temporally heterogeneous in surface water, in groundwater, as well as in exchange between the two and appeared to coexist in small areas. Immediate propagation of hydrostatic pressure into deep soils was suggested at some locations. Preferential groundwater flow was suggested in locations where the pressure and electrical conductivity signals propagated too fast for bulk Darcy flow through porous media. Preferential flow was particularly obvious where the pressure signal bypassed an intermediate depth but was observed at a deeper depth. Bulk Darcy flow in combination with preferential flow was suggested at locations where the flood pressure and electrical conductivity signal propagated more slowly yet arrived too quickly to be described using Darcy's Law. Finally, other areas exhibited no transmission of pressure or conductivity signals, indicating a complete lack of groundwater flow. Antecedent moisture affected the flood pulse arrival time and in some cases vertical connectivity with deeper sediments while vegetation density altered surface water storage volume. Understanding the variety of exchange mechanisms and their spatial variability will help understand the observed variability of floodplain impacts on water quality, and ultimately improve the effectiveness of floodplain restoration in reducing excess nutrient in river basins. / Master of Science

Recent hurricanes have made it clear that housing is the single greatest component of all losses in terms of economic value and buildings damaged. Housing damage resulting from floods has increased in the United States, despite local, state and federal encouragement to mitigate flood hazards and regulate development in flood-prone areas (Atreya, 2013). The two primary causes of these increased costs are: (1) a rise in the occurrence and strength of the extreme weather events, and (2) increased development and value of property in physically vulnerable areas. The overlap of the above two factors resulted in tremendous losses of property in Staten Island and other coastal communities along the Atlantic Coast. Hurricane Sandy was a reminder of how vulnerable such areas could be. After hurricane Sandy, damaged properties experienced higher than usual housing sales and changed property values. This research, seeks to improve the current state of knowledge about housing market following a major disaster through examining single-family housing sales and prices in Staten Island, New York. The housing price recovery rate was much slower for the properties that sustained damage, and the impacts lasted for at least four years after the storm. Researchers studying housing recovery have utilized a variety of indicators like financial characteristics, government policies, social parameters, damage, housing characteristics, etc. to capture the dimensions of recovery. In Sandy's case damage was the major influencing parameter, and it completely changed the housing dynamics of the affected coastal regions. Housing market, in terms of damage, restoration, and recovery, is a fundamental indicator of disaster resilience. Every community is different and so are the effects of disasters on residential markets. This study clearly highlights this point and underscores the importance of using contextual methods and data sets in conducting the research. / Master of Urban and Regional Planning / Recent hurricanes have made it clear that housing is the single greatest component of all losses in terms of economic value and buildings damaged. Housing damage resulting from floods has increased in the United States, despite local, state and federal encouragement to mitigate flood hazards and regulate development in flood-prone areas (Atreya, 2013). The two primary causes of these increased costs are: (1) a rise in the occurrence and strength of the extreme weather events, and (2) increased development and value of property in physically vulnerable areas. The overlap of the above two factors resulted in tremendous losses of property in Staten Island and other coastal communities along the Atlantic Coast. Hurricane Sandy was a reminder of how vulnerable such areas could be. After hurricane Sandy, damaged properties experienced higher than usual housing sales and changed property values. This research, seeks to improve the current state of knowledge about housing market following a major disaster through examining single-family housing sales and prices in Staten Island, New York. The housing price recovery rate was much slower for the properties that sustained damage, and the impacts lasted for at least four years after the storm. Researchers studying housing recovery have utilized a variety of indicators like financial characteristics, government policies, social parameters, damage, housing characteristics, etc. to capture the dimensions of recovery. In Sandy’s case damage was the major influencing parameter, and it completely changed the housing dynamics of the affected coastal regions. Housing market, in terms of damage, restoration, and recovery, is a fundamental indicator of disaster resilience. Every community is different and so are the effects of disasters on residential markets. This study clearly highlights this point and underscores the importance of using contextual methods and datasets in conducting the research.

How can architects let their buildings interact with the water while protecting occupants from the potential danger? The two intents are very different and often compete with one, either protection or recreation, as the primary program in one project. Water draws people, everyone likes being near water. People visit waterfalls and the beach just to experience moving water, they go boating and kayaking just to be on the water. Water views and access are considered an amenity that drive up prices in buildings. Whenever possible architects should strive to connect their architecture and water and to let occupants interact with the water. However, water can be dangerous too. Overfull rivers wash away roads and cars. Floods inundate entire cities, and hurricanes devastate huge islands. In addition to catastrophic damage sea levels are rising around the world causing damage and rendering low lying land uninhabitable. Architects must protect against these dangers. If designed correctly buildings can offer shelter from storms and resist rising water of all kinds. For my thesis I decided to study how to reconcile these two conflicting approaches to water. / Master of Architecture

Urban flooding presents a significant challenge to cities worldwide, resulting in loss of life and economic damage. Factors such as urbanization, climate change, and extreme weather events compound the vulnerability of urban areas to flooding, with rapid urbanization emerging as a primary driver of increased flood risk. In response to this pressing issue, this thesis embarks on a transformative exploration, advocating for a paradigm shift in urban stormwater management through the lens of "Hydro-Urbanism." Central to this concept is recognizing stormwater as a valuable resource rather than a mere liability. By implementing targeted strategies to curb runoff, detain stormwater, and replenish groundwater, cities can mitigate the adverse impacts of urban flooding while enhancing resilience and livability. Through a comprehensive review of existing literature and analysis of case studies, this research explores the efficacy of diverse stormwater management techniques in alleviating urban flooding and fostering sustainable urban development. In addition to technical aspects, the study delves into the socioeconomic dimensions of Hydro-Urbanism, highlighting the significance of community engagement and participatory planning in creating resilient and inclusive urban environments. Focused on Hyderabad city in Telangana, India, this project lies at the intersection of cultural heritage and modernity, confronting significant challenges posed by urban flooding amidst rapid urban expansion. By reframing the narrative around water from vulnerability to resilience and opportunity, the project aims to harness the power of stormwater as a catalyst for change. A tailored typology-based approach seeks to nurture a future where cities and water coexist harmoniously, protecting urban areas from flooding and fostering a more harmonious relationship between urban communities and the natural world. / Master of Science / Urban flooding, characterized by the inundation of urban streets, buildings, and infrastructure, arises when rainwater overwhelms drainage systems or water bodies overflow due to heavy rainfall or storms. It is a significant challenge faced by cities globally, leading to property damage, transportation disruptions, and risks to public safety. In response to the pressing issue of urban flooding, this project adopts a novel approach called "Hydro-Urbanism," emphasizing the interconnection between water and urban landscapes and aiming to transform how cities manage stormwater resources. Unlike traditional methods that view stormwater as a problem to be mitigated, Hydro-Urbanism recognizes stormwater as a valuable resource that can be harnessed for various purposes. It seeks to establish a symbiotic relationship between urban environments and water, wherein stormwater is managed strategically to mitigate flooding risks and enhance urban resilience while improving the quality of urban life. Amid rapid urbanization, exemplified vividly in cities like Hyderabad in the Telangana state of India, the balance between expanding urban sprawl and natural ecosystems has become increasingly fragile. Here, the challenge of managing stormwater looms large, threatening public safety, infrastructure integrity, and economic stability. Nevertheless, what if we could flip this narrative? What if stormwater could be a resource instead of being a menace? Focused on Hyderabad, a city at the crossroads of tradition and modernity, this project proposes a typology-based approach tailored to its unique urban fabric. By harnessing the potential of stormwater, the project aims to pave the way for a more resilient and adaptive urban future. Ultimately, the goal is to foster a harmonious coexistence between urban communities and stormwater resources, ensuring cities' long-term viability and well-being in the face of environmental uncertainties.

The purpose of this study was to determine the effects of amendments (control, (1x) compost, (2x) compost, (TS) topsoil, and 1x+TS) and microtopography (level, pit and mound) on three parameters (plant species composition, above-ground characteristics of Taxodium distichum, and plant root characteristics) of vegetation growing at a created tidal freshwater swamp in Virginia. None of the soil treatments met the traditional vegetation criteria for federal wetland jurisdictional determination, which only considers dominant species. When the same criteria were used for all of the species, the control, 1x, and 2x treatments met jurisdictional criteria. Considering these findings, vegetative criteria should be re-evaluated for young created wetlands. Compost addition produced the highest proportion of obligate wetland species (30%) while topsoil additions created the lowest proportion of wetland obligates (11%) and the highest proportion of upland plants. The 1x treatment generated the greatest species evenness and lowest weighted average (2.57). Topsoil treatments had the lowest diversity and evenness. Therefore, compost amendment is recommended to increase hydrophytes without compromising evenness and diversity. Bald cypress in pits were taller, had larger trunk diameter and basal trunk swelling than trees growing at higher elevations. Roots growing in mounds were more numerous with greater length than roots at lower elevations. Root length and count were highest for the control soil treatment. Amended treatments may have had lower rooting values because nutrient supply was adequate. Overall, incorporating microtopography and compost during wetland creation had a positive effect on vegetative function in this system. / Master of Science

<div>Multicore architectures employ multiple processing cores that work together for greater processing power. Shared memory, symmetric multiprocessor (SMP) systems are ubiquitous. All software must be explicitly designed to support SMP processing, including operating systems. XINU is a simple, lightweight, elegant operating system that has existed for several decades and has been ported to many platforms. However, XINU has never been extended to support multicore processing. This project incrementally adds SMP support to the XINU operating system. Core kernel modules, including the scheduler and memory manager, have been successfully extended without overhauling or completely redesigning XINU. A multicore methodology is laid out for the remaining kernel modules.</div><p></p>

Natural disasters have become more severe and frequent than previous assessments with global warming. The increasing risk of natural disasters presents different groups of populations with diverse vulnerabilities, particularly those underrepresented social groups which need specific support before, during, and after extreme disasters. Hence, it is highly desired to examine vulnerability quantitatively and qualitatively across different social groups in risk to natural disasters. This dissertation study aims to investigate the measure of social vulnerability to two types of climate change-related natural disasters: sea-level-rise floodings and wildfires. In the study of sea-level-rise floodings, high-risk flooding areas are first identified for a coastal city. Then, we measure social vulnerability index (SVI) using a new SVI metric to identify vulnerable social groups which should be paid more attention for coastal flooding disaster mitigation. Compared to existing SVI methods, the new SVI leverages principal component analysis and analytic hierarchy process to achieve a better social vulnerability analysis. In the study of wildfires, we focus on the understanding of minority vulnerabilities and their disparities to wildfires over time and space. Minority vulnerabilities are analyzed with spatial clustering methods including Local Moran’s I and Getis-Ord Gi*. The vulnerability disparity is measured based on a reference point from which the quantity separates a minority group on a particular place. Both location quotient and location amplitude index are used to quantitively measure the vulnerability disparity among different minorities. Lastly, in addition to the “direct” impact of disasters on vulnerable population, this dissertation study also conducts vulnerability analysis to failed infrastructure (e.g., power systems) due to disasters, i.e., the “indirect” impact of disasters on different social groups. Recently, scheduled power outages known as Public Safety Power Shutoff (PSPS) are becoming increasingly common to mitigate threats of wildfires to power systems. However, current PSPS decision making processes do not consider the unequal distribution of various social groups, particularly those who are more vulnerable to the power outage. This study investigates the measure of social vulnerability in high-risk fire areas to PSPS, which will help decision makers to better determine the efficiency of a PSPS event for wildfire mitigation.

Floodplain lakes are strongly regulated by river connectivity because floodwaters exert strong influence on the water balance, the physical, chemical and biological limnological conditions, and the influx of contaminants. The Peace-Athabasca Delta (PAD) in northern Alberta (Canada) is a hydrologically complex landscape and is an important node in the upper Mackenzie River Drainage Basin. The ecological integrity of the PAD is potentially threatened by multiple environmental stressors, yet our understanding of the hydroecology of this large floodplain remains underdeveloped. Indeed, ever since the planning and construction of the WAC Bennett Dam (1960s), concerns have grown over the effects of upstream human activities on the lakes of the PAD. More recently, concerns over the health of the PAD have intensified and come to the fore of national and international dialogue due to water abstraction and mining and processing activities by the rapidly expanding oil sands industry centred in Fort McMurray Alberta. Currently, widespread perception is that upstream human activities have reduced water levels and frequency of flooding at the PAD, which have lowered nutrient availability and productivity of perched basin lakes, and have increased supply of pollutants from oil sands. However, these perceptions remain based on insufficient knowledge of pre-impact conditions and natural variability. Current and past relations between hydrology and limnology of PAD lakes are mostly undocumented, particularly during the important spring freshet period when the effects of river flood waters are strongest. Similarly, knowledge of the deposition of oil-sands- related contaminants in the PAD remains insufficient to determine whether anthropogenic activities have increased the deposition of important oil-sands-related contaminants such as polycyclic aromatic compounds (PACs) relative to natural processes. Such knowledge gaps must be filled to achieve effective monitoring, policy and governance concerning impacts of industrial development and the protection of human and environmental health within the PAD and Mackenzie drainage basin. This thesis examines the effects of river flooding (and the lack of) on water clarity, nutrients, chemistry, phytoplankton abundance, epiphyton community composition and the deposition of polycyclic aromatic compounds (PACs) in lakes of the Peace-Athabasca Delta. To determine the role of flooding on contemporary epiphytic diatom communities (an abundant and diverse guild of primary producers in PAD lakes), a field experiment was conducted examining the community composition and abundance of epiphytic diatoms in four PAD lakes. Two of these four lakes had received floodwaters that spring and two had not. Epiphytic diatom communities in each lake were sampled during the peak macrophyte biomass period (summer) from two macrophyte taxa (Potamogeton zosteriformis, P. perfoliatus var. richardsonii) and from polypropylene artificial substrates previously deployed that spring. A two-way analysis of similarity (ANOSIM) test identified that epiphytic diatom community composition differed between lakes that flooded and those that did not flood. From the use of similarity percentage (SIMPER) analysis, diatom taxa were identified that discriminate between flooded and non-flooded lakes. The relative abundance of ‘strong flood indicator taxa’ was used to construct an event-scale flood record spanning the past ~180 years using analyses of sedimentary diatom assemblages from a closed-drainage lake (PAD 5). Results were verified by close agreement with an independent paleo-flood record from a nearby flood-prone oxbow lake (PAD 54) and historical records. Comparison of epiphytic diatoms in flooded and non-flooded lakes in this study provides a promising approach to detect changes in flood frequency, and may have applications for reconstructing other pulse-type disturbances such as hurricanes and pollutant spills. Additionally, this study demonstrates that artificial substrates can provide an effective bio-monitoring tool for lakes of the PAD and elsewhere. To improve our understanding of the hydrolimnological responses of lake in the PAD to flooding, repeated measurements over three years (2003-05) were made on a series of lakes along a hydrological gradient. This allowed the role of river flooding to be characterized on limnological conditions of lakes and to identify the patterns and timescales of limnological change after flooding. River floodwaters elevate lake water concentrations of suspended sediment, total phosphorus (TP), SO4 and dissolved Si (DSi), and reduce concentrations of total Kjeldahl nitrogen (TKN), DOC and most ions. River flooding increases limnological homogeneity among lakes, because post-flood conditions are strongly affected by the river water properties. After floodwaters recede, limnological conditions become more heterogeneous among lakes in response to diversity of local basin influences (geology, slope, vegetation, depth, fetch, and biological communities and processes), and limnological changes occur at two distinct timescales. In the weeks to months after flooding, water clarity increases as suspended sediments and TP settle out of the water column. In the absence of flooding for many years to decades, evaporative concentration leads to an increase in most nutrients (TKN, inorganic N, and dissolved P), DOC and ions. Contrary to a prevailing paradigm, these results suggest that regular flooding is not required to maintain high nutrient concentrations. In light of anticipated declines in river discharge, limnological conditions in the southern Athabasca sector will become increasingly less dominated by the short-term effects of flooding, and resemble nutrient- and solute-rich lakes in the northern Peace sector that are infrequently flooded. To determine the roles of the Athabasca River and atmospheric transport as vectors for the deposition of PACs in the PAD, sediment cores spanning the last ~200 years were collected from three lakes within the delta. A closed-drainage basin elevated well above the floodplain (PAD 18) was selected to determine temporal patterns of change in PAC concentration due to atmospheric deposition and within-basin production of PACs. Known patterns of paleohydrological changes at the other two lakes (PAD 23 and 31) were used to assess the role of the Athabasca River in delivering PACs to the Athabasca Delta during the ~200 year. Well- dated sediment core samples were analysed for 52 alkylated and non-alkylated PACs (method EPA 3540/8270-GC/MS). Sediments deposited in the non-flood prone lake (PAD 18) contained lower concentrations of total PACs compared to sediments deposited during flood-prone periods in the other study lakes, and were dominated by PACs of a pyrogenic rather than bitumen origin. Multivariate analysis of similarity tests identified that the composition of PACs differs between sediments deposited during not flood-prone and flood-prone periods. Subsequent Similarities Percentage (SIMPER) analysis was used and identified seven PACs that are preferentially deposited during flood-prone periods. These seven PACs are bitumen-associated, river-transported and account for 51% of the total PACs found in oil-sands sediment. At PAD 31, which has been flood-prone both before and since onset of Athabasca oil sands development, identified no measureable differences in both the proportion and concentration of the river-transported indicator PACs in sediments deposited pre-1940s versus post-1982. Our findings suggest that natural erosion of exposed bitumen along the banks of the Athabasca River and its tributaries is the main process delivering PACs to the Athabasca Delta, and that the spring freshet is a key period for contaminant mobilization and transport. Such key baseline environmental information is essential for informed management of natural resources and human-health concerns by provincial and federal regulatory agencies and industry, and for designing effective long-term monitoring and surveillance programs for the lower Athabasca River watershed in the face of future oil sands development. Further monitoring activities and additional paleolimnological studies of the depositional history of PACs and other oil-sands- and non-oil-sands-related contaminants is strongly recommended. Overall, results of this research identify that river flooding exerts strong control on physical, chemical and biological conditions of lakes within the PAD. However, contrary to prevailing paradigms, the PAD is not a landscape that has been adversely and permanently affected by regulation of the Peace River and industrial development of the oil sands along the Athabasca River. Instead, data from contemporary and paleolimnological studies identify that natural processes continue to dominate the delivery of water and contaminants to the delta. Regular and frequent flooding is not essential to maintain the supply of nutrients and productivity of delta lakes, which has been a widespread paradigm that developed in the absence of objective scientific data. Instead, nutrient concentrations rise over years to decades after flooding and lake productivity increases. During the thesis research, novel approaches were developed and demonstrated to be effective. Namely, new artificial substrate samplers were designed for aquatic biomonitoring that accrue periphyton and can identify the occurrence of flood events. Also, paleolimnological methods were employed to characterize the composition and concentration of PACs supplied by natural processes prior to oil sands industrial activity, which serves as an important benchmark for assessing industrial impacts. These are effective methods that can be employed to improve monitoring programs and scientific understanding of the factors affecting this world-renowned landscape, as well as floodplains elsewhere.