scholarly journals NATURE-BASED COASTAL PROTECTION USING LARGE WOODY DEBRIS

2020 ◽  
pp. 8
Author(s):  
Jessica Wilson ◽  
Ioan Nistor ◽  
Majid Mohammadian ◽  
Andrew Cornett ◽  
Pauline Falkenrich ◽  
...  
Keyword(s):  
Large Scale ◽  
Woody Debris ◽  
Field Investigation ◽  
Large Woody Debris ◽  
Coastal Protection ◽  
Systematic Research ◽  
Field Investigations ◽  
Extensive Field ◽  
Study Methodology ◽  
Run Up

In British Columbia (BC), Canada, and Washington State, USA, anchored Large Woody Debris (LWD) have been extensively used with the specific aim of reducing erosion and limiting wave run-up. Despite its frequent usage, there is currently limited peer-reviewed literature on the design or efficacy of coastal protection using LWD. This paper presents the results of the first systematic research project on this topic, which involved (1) extensive field investigations of existing anchored LWD projects, and (2) large-scale experimental wave modeling of simulated LWD on a gravel beach. The full paper will present an overview of the study methodology, field investigation and experimental modeling results, and provide initial design guidance for the use of coastal protection using anchored LWD.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/ktjVWGfXylk

scholarly journals Nature-Based Coastal Protection by Large Woody Debris as Compared to Seawalls: A Physical Model Study of Beach Morphology and Wave Reflection

Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2020
Author(s):  
Pauline Falkenrich ◽  
Jessica Wilson ◽  
Ioan Nistor ◽  
Nils Goseberg ◽  
Andrew Cornett ◽  
...  
Keyword(s):  
Large Scale ◽  
Wave Reflection ◽  
Woody Debris ◽  
Large Woody Debris ◽  
Wall Structure ◽  
Future Research ◽  
Coastal Protection ◽  
Suitable Alternative ◽  
Beach Morphology ◽  
The North

Anchored Large Woody Debris (LWD) is increasingly being used as one of several nature-based coastal protection strategies along the north-western coasts of Canada and the US. As an alternative to conventional hard armoring (e.g., seawalls), its usage is widely considered to be less harmful to the coastal ecosystem while maintaining the ability to protect the beaches against wave attack and erosion. The effects of seawalls on beaches have been extensively studied; however, the performance and efficacy of LWD and its potential as a suitable alternative to seawalls (and other shoreline protection structures) are still understudied in current research. This paper presents and compares the effects of a conventional vertical seawall with two different LWD structures on beach morphology and wave reflection through large-scale physical modeling in a wave flume at a 1:5 scale. An assessment of techniques used to measure beach morphology and an assessment of model effects were included in the study. It was found that the wave reflection could be reduced by using a single log instead of a wall structure, while changes in the beach morphology response largely depended on the type of the LWD structure. A stacked log wall showed near-identical behavior as a conventional seawall. Visible model effects from the experiments, including the effect of the flume sidewalls on the beach morphology, were quantified and analyzed to inform future research.

scholarly journals Comparison of Large Woody Debris Prototypes in a Large Scale Non-flume Physical Model

2018 ◽  
Vol 40 ◽  
pp. 05010
Author(s):  
Brian Perry ◽  
Colin Rennie ◽  
Andrew Cornett ◽  
Paul Knox
Keyword(s):  
Physical Model ◽  
Flood Control ◽  
Large Scale ◽  
Woody Debris ◽  
Water Levels ◽  
Mitigation Strategies ◽  
Large Woody Debris ◽  
Debris Accumulation ◽  
The Impact ◽  
The City

Due to excessive rainfall in June of 2013, several rivers located in and near the City of Calgary, Canada experienced significant flooding events. These events caused severe damage to infrastructure throughout the city, precipitating a renewed interest in flood control and mitigation strategies for the area. A major potential strategy involves partial diversion of Elbow River flood water to the proposed Springbank Off-Stream Storage Reservoir. A large scale physical model study was conducted to optimize and validate the design of a portion of the new project. The goals of the physical model were to investigate diversion system behaviors such as flow rates, water levels, sediment transport and, debris accumulation, and optimize the design of new flow control structures to be constructed on the Elbow River. In order to accurately represent the behavior of debris within the system due to flooding, large woody debris created from natural sources was utilized in the physical model and its performance was compared to that of debris of the same size fabricated from pressed cylindrical wood dowels. In addition to comparing the performance of these two debris types, the impact of root wads on debris damming was also investigated. Significant differences in damming behavior was shown to exist between the natural debris and the fabricated debris, while the impact of root wad on damming affected the dam structure and formation. The results of this experiment indicate that natural debris is preferred for studies involving debris accumulation.

scholarly journals Triggering Influence of Seasonal Agricultural Irrigation on Shallow Loess Landslides on the South Jingyang Plateau, China

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1474 ◽  
Author(s):  
Rui-Xin Yan ◽  
Jian-Bing Peng ◽  
Qiang-Bing Huang ◽  
Li-Jie Chen ◽  
Chen-Yun Kang ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Large Scale ◽  
Field Investigation ◽  
Agricultural Irrigation ◽  
The South ◽  
Field Investigations ◽  
Static Liquefaction ◽  
Loess Landslides ◽  
Developmental Characteristics ◽  
Agricultural Areas

Since large-scale agricultural irrigation began in the 1980s, 92 landslides have occurred around the South Jingyang Plateau during the past 40 years. The geological disaster and soil erosion have caused numerous casualties and substantial property loss. In this work, several field investigations are carried out to explore the soil erosion and mechanical mechanism of these irrigated shallow loess landslides on the South Jingyang Plateau. (1) We investigated the spatial distributions, types and developmental characteristics of loess landslides. (2) We surveyed and monitored seasonal agricultural irrigation features and groundwater changes in the area since the 1980s and found that irrigation is a significant factor influencing groundwater changes, soil erosion and even causing landslides to occur. (3) Based on the field investigation, the occurrence of these irrigated shallow loess landslides was generalized, and it was found that the core process was due to the liquefaction of softening zone. We carried out a static liquefaction test and verified that the natural loess was prone to liquefaction. (4) The three main reasons for shallow loess landslides in the South Jingyang Plateau were discussed. This study provides a valuable reference for achieving an understanding of the relationship between seasonal agricultural irrigation and the occurrence of loess landslides in the area as well as similar irrigated agricultural areas.

scholarly journals THE JAVA TSUNAMI MODEL: USING HIGHLY-RESOLVED DATA TO MODEL THE PAST EVENT AND TO ESTIMATE THE FUTURE HAZARD

2011 ◽  
Vol 1 (32) ◽  
pp. 25 ◽  
Author(s):  
Widjo Kongko ◽  
Torsten Schlurmann
Keyword(s):  
Sand Dunes ◽  
Accretionary Prism ◽  
Mitigation Measures ◽  
Coastal Protection ◽  
Observation Data ◽  
Maximum Magnitude ◽  
Inundation Area ◽  
Extensive Field ◽  
Run Up ◽  
Tsunami Model

This study is to validate the tsunami model with extensive field observation data gathered from the 2006 Java tsunami. In the relevant study area, where highly-resolved geometric data were recently made available and other related post-tsunami field data have been collected, the tsunami maximum run-up onto land and its marigram have been simulated and evaluated. Several plausible tsunami sources are proposed to adequately mimic the 2006 Java tsunami by including the influence of low rigidity material in the accretionary prism as well as its single-multi fault source type’s effect. Since it has a significant role on tsunami excitation, this parameter and other assumptions are then employed to study an estimated set of reasonable maximum magnitude earthquake-tsunami scenario and projected inundation areas for probable future tsunami on the South Java coastline. In a final step tentative technical mitigation measures are proposed and assessed to deal with adequate coastal protection issues by means of soft (greenbelt, etc.) and hard engineering (sand dunes, etc.) approaches. Their effectiveness in terms of reducing inundation area is assessed and general recommendations for coastal planning authorities are dealt with.

Restoring barrier habitat in Louisiana to compensate for natural resource injuries: Shell Island and Chenier Ronquille Barrier Restoration Projects

Shore & Beach ◽  
2020 ◽  
pp. 65-71
Author(s):  
Whitney Thompson ◽  
Christopher Paul ◽  
John Darnall
Keyword(s):  
Gulf Of Mexico ◽  
Natural Resource ◽  
Large Scale ◽  
Barrier Island ◽  
Deepwater Horizon ◽  
Coastal Protection ◽  
Restoration Project ◽  
Island Restoration ◽  
Barataria Basin ◽  
Outer Coast

Coastal Louisiana received significant funds tied to BP penalties as a result of the Deepwater Horizon incident. As it is widely considered that the State of Louisiana sustained most of the damage due to this incident, there has been a firm push to waste no time in implementing habitat restoration projects. Sustaining the land on the coast of Louisiana is vital to our nation’s economy, as several of the nation’s largest ports are located on the Gulf coast in Louisiana. In addition, the ecosystems making up the Louisiana coast are important to sustain some of the largest and most valuable fisheries in the nation. Funded by BP Phase 3 Early Restoration, the goals of the Natural Resource Damage Assessment (NRDA) Outer Coast Restoration Project are to restore beach, dune, and marsh habitats to help compensate spill-related injuries to habitats and species, specifically brown pelicans, terns, skimmers, and gulls. Four island components in Louisiana were funded under this project; Shell Island Barrier Restoration, Chenier Ronquille Barrier Island Restoration, Caillou Lake Headlands Barrier Island Restoration, and North Breton Island Restoration (https://www. gulfspillrestoration.noaa.gov/louisiana-outer-coast-restoration, NOAA 2018). Shell Island and Chenier Ronquille are critical pieces of barrier shoreline within the Barataria Basin in Plaquemines Parish, Louisiana. These large-scale restoration projects were completed in the years following the Deepwater Horizon incident, creating new habitat and reinforcing Louisiana’s Gulf of Mexico shoreline. The Louisiana Coastal Protection and Restoration Authority (CPRA) finished construction of the Shell Island NRDA Restoration Project in 2017, which restored two barrier islands in Plaquemines Parish utilizing sand hydraulically dredged from the Mississippi River and pumped via pipeline over 20 miles over levees and through towns, marinas, and marshes to the coastline. The National Marine Fisheries Service (NMFS) also completed the Plaquemines Parish barrier island restoration at Chenier Ronquille in 2017 utilizing nearshore Gulf of Mexico sediment, restoring wetland, coastal, and nearshore habitat in the Barataria Basin. A design and construction overview is provided herein.

scholarly journals Universal Masking to Control Healthcare-Associated Transmission of SARS-CoV-2

2021 ◽  
pp. 1-24
Author(s):  
Eliza R. Thompson ◽  
Faith S. Williams ◽  
Pat A. Giacin ◽  
Shay Drummond ◽  
Eric Brown ◽  
...  
Keyword(s):  
Large Scale ◽  
Infection Prevention ◽  
Index Patient ◽  
Field Investigation ◽  
Point Prevalence ◽  
Control Measures ◽  
Prevention Measures ◽  
Infection Control Measures ◽  
Va Health Care System ◽  
Healthcare Associated

Abstract Objective: To assess extent of a healthcare-associated outbreak of SARS-CoV-2 and evaluate effectiveness of infection control measures, including universal masking Design: Outbreak investigation including 4 large-scale point-prevalence surveys Setting: Integrated VA Health Care System with 2 facilities and 330 beds Participants: Index patient and 250 exposed patients and staff Methods: We identified exposed patients and staff and classified them as probable and confirmed cases based on symptoms and testing. We performed a field investigation and assessment of patient and staff interactions to develop probable transmission routes. Infection prevention interventions implemented included droplet and contact precautions, employee quarantine, and universal masking with medical and cloth facemasks. Four point-prevalence surveys of patient and staff subsets were conducted using real-time reverse-transcriptase polymerase chain reaction for SARS-CoV-2. Results: Among 250 potentially exposed patients and staff, 14 confirmed cases of Covid-19 were identified. Patient roommates and staff with prolonged patient contact were most likely to be infected. The last potential date of transmission from staff to patient was day 22, the day universal masking was implemented. Subsequent point-prevalence surveys in 126 patients and 234 staff identified 0 patient cases and 5 staff cases of Covid-19, without evidence of healthcare-associated transmission. Conclusions: Universal masking with medical facemasks was effective in preventing further spread of SARS-CoV-2 in our facility in conjunction with other traditional infection prevention measures.

scholarly journals Assessment of Numerical Methods for Plunging Breaking Wave Predictions

2021 ◽  
Vol 9 (3) ◽  
pp. 264
Author(s):  
Shanti Bhushan ◽  
Oumnia El Fajri ◽  
Graham Hubbard ◽  
Bradley Chambers ◽  
Christopher Kees
Keyword(s):  
Solitary Wave ◽  
Wave Breaking ◽  
Large Scale ◽  
Turbulence Models ◽  
Navier Stokes ◽  
Wave Crest ◽  
Breaking Wave ◽  
Rans Turbulence Models ◽  
Run Up ◽  
Better Than

This study evaluates the capability of Navier–Stokes solvers in predicting forward and backward plunging breaking, including assessment of the effect of grid resolution, turbulence model, and VoF, CLSVoF interface models on predictions. For this purpose, 2D simulations are performed for four test cases: dam break, solitary wave run up on a slope, flow over a submerged bump, and solitary wave over a submerged rectangular obstacle. Plunging wave breaking involves high wave crest, plunger formation, and splash up, followed by second plunger, and chaotic water motions. Coarser grids reasonably predict the wave breaking features, but finer grids are required for accurate prediction of the splash up events. However, instabilities are triggered at the air–water interface (primarily for the air flow) on very fine grids, which induces surface peel-off or kinks and roll-up of the plunger tips. Reynolds averaged Navier–Stokes (RANS) turbulence models result in high eddy-viscosity in the air–water region which decays the fluid momentum and adversely affects the predictions. Both VoF and CLSVoF methods predict the large-scale plunging breaking characteristics well; however, they vary in the prediction of the finer details. The CLSVoF solver predicts the splash-up event and secondary plunger better than the VoF solver; however, the latter predicts the plunger shape better than the former for the solitary wave run-up on a slope case.

scholarly journals Sustainable Spatial Energy Planning of Large-Scale Wind and PV Farms in Israel: A Collaborative and Participatory Planning Approach

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 551
Author(s):  
Sofia Spyridonidou ◽  
Georgia Sismani ◽  
Eva Loukogeorgaki ◽  
Dimitra G. Vagiona ◽  
Hagit Ulanovsky ◽  
...  
Keyword(s):  
Large Scale ◽  
Wind Farms ◽  
Field Investigation ◽  
Participatory Planning ◽  
Energy Planning ◽  
Environmentally Sustainable ◽  
Selection Processes ◽  
Planning Framework ◽  
Planning Approach ◽  
Near Future

In this work, an innovative sustainable spatial energy planning framework is developed on national scale for identifying and prioritizing appropriate, technically and economically feasible, environmentally sustainable as well as socially acceptable sites for the siting of large-scale onshore Wind Farms (WFs) and Photovoltaic Farms (PVFs) in Israel. The proposed holistic framework consists of distinctive steps allocated in two successive modules (the Planning and the Field Investigation module), and it covers all relevant dimensions of a sustainable siting analysis (economic, social, and environmental). It advances a collaborative and participatory planning approach by combining spatial planning tools (Geographic Information Systems (GIS)) and multi-criteria decision-making methods (e.g., Analytical Hierarchy Process (AHP)) with versatile participatory planning techniques in order to consider the opinion of three different participatory groups (public, experts, and renewable energy planners) within the site-selection processes. Moreover, it facilitates verification of GIS results by conducting appropriate field observations. Sites of high suitability, accepted by all participatory groups and field verified, form the final outcome of the proposed framework. The results illustrate the existence of high suitable sites for large-scale WFs’ and PVFs’ siting and, thus, the potential deployment of such projects towards the fulfillment of the Israeli energy targets in the near future.

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