Margery Overton
Education
Ph.D. Civil Engineering Duke University 1981
M.S. Civil Engineering Duke University 1978
B.S. Civil Engineering Duke University 1976
Area(s) of Expertise
Dr. Overton is interested in coastal processes, beach and dune erosion, coastal hazard identification and response strategies to improve the resilience of coastal environments. Modeling and analysis of both short term and long term impacts due to storms and sea level rise.
Publications
- Formation of a barrier island breach and its contributions to lagoonal circulation , ESTUARINE COASTAL AND SHELF SCIENCE (2021)
- Land cover changes on a barrier island: Yearly changes, storm effects, and recovery periods , APPLIED GEOGRAPHY (2021)
- Vulnerability Indicators for Coastal Roadways Based on Barrier Island Morphology and Shoreline Change Predictions , NATURAL HAZARDS REVIEW (2021)
- Storm-driven erosion and inundation of barrier islands from dune-to region-scales , COASTAL ENGINEERING (2020)
- Natural and anthropogenic-induced changes in a tidal inlet: Morphological evolution of Oregon Inlet , GEOMORPHOLOGY (2019)
- Observation and modeling of the evolution of an ephemeral storm-induced inlet: Pea Island Breach, North Carolina, USA , Continental Shelf Research (2018)
- Beach Management Practices and Occupation Dynamics: An Agent-Based Modeling Study for the Coastal Town of Nags Head, NC, USA , BEACH MANAGEMENT TOOLS - CONCEPTS, METHODOLOGIES AND CASE STUDIES (2017)
- Spatial and temporal variability in dune field: Pea Island, North Carolina , Shore & Beach, Coastal Observations (2016)
- Guest Editorial: Coastal Dunes Essential to a Resilient Coast , Shore & Beach (2014)
- Least cost path extraction of topographic features for storm impact scale mapping , Journal of Coastal Research (2012)
Grants
In August 2012, a new terminal groin permit associated with the new Basnight Bridge was signed. As with the original (1989) Oregon Inlet Terminal Groin permit, the new permit requires NC DOT to monitor the adjacent beach in order to determine whether or not there is adverse impact of the presence of the terminal groin, including a determination of whether sediment loss is greater than that predicted by the historical rates. In addition, NC DOT has proposed coastal and biological monitoring in support of the NC 12 Transportation Management Plan (NC 12 TMP) alternative (as discussed in the B-2500 ROD) and a review of the historical rate used for a basis comparison. The monitoring associated with the NC 12 TMP is needed in order to determine the location and extent of future phases of the B-2500 project. This study will gather and analyze the data that is needed to satisfy the requirements of both 1) the new terminal groin permit and 2) the coastal monitoring program component of the NC 12 TMP. The present proposal includes the following program elements: 1) data collection by NC DOT, 2) monitoring of the existing Oregon Inlet terminal groin, 3) mapping and modeling of coastal habitat changes, 4) TMP coastal monitoring, including development of vulnerability indicators related to the island morphology, and 5) integration of physical and biological monitoring data from NC DOT with the morphological indicators. An annual report will be developed detailing the program tasks and annual results, including a comparison with baseline conditions.
In August 2012, a new terminal groin permit associated with the new (currently under construction) Bonner Bridge was signed. As with the original (1989) Oregon Inlet Terminal Groin permit, the new permit requires NC DOT to monitor the adjacent beach in order to determine whether or not there is adverse impact of the presence of the terminal groin, including a determination of whether sediment loss is greater than that predicted by the historical rates. In addition, NC DOT has proposed coastal and biological monitoring in support of the NC 12 Transportation Management Plan (NC 12 TMP) alternative (as discussed in the B-2500 ROD) and a review of the historical rate used for a basis comparison. The monitoring associated with the NC 12 TMP is needed in order to determine the location and extent of future phases of the B-2500 project. This study will gather and analyze the data that is needed to satisfy the requirements of both 1) the new terminal groin permit and 2) the coastal monitoring program component of the NC 12 TMP. The present proposal includes the following program elements: 1) data collection by NC DOT, 2) monitoring of the existing Oregon Inlet terminal groin, 3) mapping and modeling of coastal habitat changes, 4) TMP coastal monitoring, including development of vulnerability indicators related to the island morphology, and 5) integration of physical and biological monitoring data from NC DOT with the morphological indicators. An annual report will be developed detailing the program tasks and annual results, including a comparison with baseline conditions.
Our goal is to improve simulations of coastal flooding in regions where the beach morphology is highly dynamic during a storm event. The feedback between waves, surge and morphology must be better linked, specifically through the extension and coupling of state-of-the-art numerical models. Although most morphology models are limited in their geographic extents, we will extend and apply a process-driven model to represent erosion and breaching at larger scales. And, although most wave, surge and morphology models are coupled with one-way communication, we will develop an automated system to map information in both ways. This research will produce modeling technologies that will benefit coastal communities within North Carolina, and we will share these technologies and findings with stakeholders. Simulations of wave propagation and flooding (and specifically the simulations from our models) are used in North Carolina and elsewhere for building design, the establishment of flood insurance rates, and real-time decision support during storm events. These predictions will be strengthened via the proposed tight coupling with a beach morphology model. The resulting modeling system will better represent the nearshore response to storm impacts.
The purpose of this research is to develop dune construction guidelines for overtopping, for projects where a constructed beach berm affects the maximum runup elevation. Many local communities planning a beach and dune nourishment program find that the distance between established infrastructure (e.g., roads, buildings, etc.) and the active shoreline limits the horizontal extent of a project. In these cases, it is critical to design the dune such that it can resist overtopping and mitigate damage to that infrastructure. Most current methods to assess runup elevation (e.g., Holman 1986, Stockdon et al. 2006) are dependent on the beach slope and wave height, but do not incorporate the effects of a constructed berm width. This likely over-predicts the runup elevation which would lead to an overdesigned (and more expensive) dune; such a dune might not even be feasible to construct in an area where the distance of the infrastructure to the shoreline is small. In those situations where space is limited, a ����������������starter dune��������������� which will resist overtopping while it is allowed to grow naturally can be designed. It is hypothesized based on previous work (de Waal and van der Meer 1992) that an equivalent beach slope can be developed incorporating the effects of the berm and used in empirical formulations to assess runup. This project will test this hypothesis using measured wave, high water mark (runup limit), and nearshore profile slope data collected prior to and after beach and dune nourishment in the Town of Kitty Hawk, North Carolina. XBeach modeling will also be performed and calibrated with field data to assess runup and overtopping with different berm width and elevation scenarios. Project partners include the Town of Kitty Hawk, the consulting firm that designed and is managing the beach and dune nourishment project for the town, CB&I, the USACE Field Research Facility, and North Carolina State University Department of Civil, Construction, and Environmental Engineering. Primary deliverables include dune construction guidelines for overtopping, for projects where a constructed beach berm affects the maximum runup elevation. These guidelines will be communicated in three ways: 1) a workshop to be conducted with town representatives, 2) a presentation at the ASBPA National Coastal Conference in Fall 2017 and 3) a peer-reviewed publication communicating results to the larger research community.
The Department of the Interior (DOI) is establishing a network of geographically dispersed DOI Regional Climate Science Centers (Regional Centers). Regional Centers will be based at host organizations that have suitable facilities, partnerships, and science capabilities, and will involve multiple active collaborators. Regional Centers will house up to twelve (12) USGS and DOI employees and will work in close partnership with the host institution with the goal to understand high priority science needs and to develop science information and tools that can help land, water, fish and wildlife, and cultural heritage resource managers develop strategies for responding to climate change. Objectives are to 1) Provide land, water, fish and wildlife, ocean, coastal, and cultural heritage resource managers with the tools and information to develop and execute strategies for successfully adapting to and mitigating the impacts of climate change. 2) Provide modeling and forecasting information and tools, integrate physical climate models with ecological models, assess climate change vulnerabilities, forecast changes, and develop standardized approaches. 3) Provide funding for researchers through cooperative agreements that involve climate change science as a major component.
The purpose of this ongoing project (1989 to present) is to monitor and evaluate the shoreline response north and south of the Oregon Inlet due to the construction of the terminal groin built to protect Bonner Bridge at the north end of Pea Island. Phase one of the study was to establish the 'historical erosion rates' for the study area since the change in dredging operations in the inlet in 1984 and before the March 1989 storm. Phase two of the study (ongoing since 1989), was to implement the monitoring program as per the permit requirement to determine position of the shoreline from aerial photography at a two month interval and to evaluate the response of the shoreline in the context of the historical erosion rates. The monitoring agreement specified the triggers and actions if the observed erosion exceeded the historic values over spatial and temporal scales of concern. This monitoring effort continues in support of the new permit for the Oregon Inlet Terminal Groin which was issued in August 2012. As part of the construction of the new Bonner Bridge, Phase three of the project has been established and is underway to monitor an expanded project area and set of metrics in order to inform decision making with respect the NC 12 corridor. This scope has been added to the ongoing terminal groin monitoring project in anticipation of future design and planning need for the NC12 transportation corridor.
The purpose of this ongoing project (1989 to present) is to monitor and evaluate the shoreline response north and south of the Oregon Inlet due to the construction of the terminal groin built to protect Bonner Bridge at the north end of Pea Island. Phase one of the study was to establish the 'historical erosion rates' for the study area since the change in dredging operations in the inlet in 1984 and before the March 1989 storm. Phase two of the study (1989 through 2012), was to implement the monitoring program as per the permit requirement to determining position of the shoreline from aerial photography at a two month interval and to evaluate the response of the shoreline in the context of the historical erosion rates. The monitoring agreement specified the triggers and actions if the observed erosion exceeded the historic values over spatial and temporal scales of concern. This monitoring effort continues in support of the permit for the Oregon Inlet Terminal Groin. With the negotiation of the permit for the construction of the new Bonner Bridge, monitoring requirements for an expanded project area and for additional metrics have been defined. This scope has been added to the ongoing terminal groin monitoring project in anticipation of future design and planning need for the NC12 transportation corridor.
The purpose of this ongoing project (1989 to present) is to monitor and evaluate the shoreline response north and south of the Oregon Inlet due to the construction of the terminal groin built to protect Bonner Bridge at the north end of Pea Island. Phase one of the study was to establish the 'historical erosion rates' for the study area since the change in dredging operations in the inlet in 1984 and before the March 1989 storm. Phase two of the study (1989 through 2012), was to implement the monitoring program as per the permit requirement to determining position of the shoreline from aerial photography at a two month interval and to evaluate the response of the shoreline in the context of the historical erosion rates. The monitoring agreement specified the triggers and actions if the observed erosion exceeded the historic values over spatial and temporal scales of concern. This monitoring effort continues in support of the permit for the Oregon Inlet Terminal Groin. With the negotiation of the permit for the construction of the new Bonner Bridge, monitoring requirements for an expanded project area and for additional metrics have been defined. This scope has been added to the ongoing terminal groin monitoring project in anticipation of future design and planning need for the NC12 transportation corridor.
The dynamic evolution of landforms under stress can lead to catastrophic loss of either functionality or of mass itself. This project will examine the dynamics of landforms undergoing a transition from one state to another (e.g., barrier island collapse, wetland loss, dune erosion) in order to determine critical defining features of the resilient natural and developed landforms. This descriptive dynamic will be translated into design parameters for restoration of protective or beneficial landforms (e.g., beaches, dunes, barrier islands, wetlands). In addition, this analysis will be used to provide improved metrics for communicating hazard and risk as well as incorporating hazard and risk into land use plans. This project lies at the interface between Coastal Hazards Science and Planning for Resilience focus areas and has the potential to provide insights to the Hazards, Human Behavior and Economic Resilience focus area.
The purpose of this proposal is to establish a graduate research fellowship program to train students to be future leaders in the area of engineering of resilient civil infrastructure systems for coastal regions considering natural hazards. This program will be conducted in coordination with the ongoing DHS Center of Excellence on Natural Disasters, Coastal Infrastructure and Emergency Management.
The purpose of this ongoing project (1989 to present) is to monitor and evaluate the shoreline response north and south of the Oregon Inlet due to the construction of the terminal groin built to protect Bonner Bridge at the north end of Pea Island. Phase one of the study was to establish the 'historical erosion rates' for the study area since the change in dredging operations in the inlet in 1984 and before the March 1989 storm. Phase two of the study (1989 through 2012), was to implement the monitoring program as per the permit requirement to determining position of the shoreline from aerial photography at a two month interval and to evaluate the response of the shoreline in the context of the historical erosion rates. The monitoring agreement specified the triggers and actions if the observed erosion exceeded the historic values over spatial and temporal scales of concern. This monitoring effort continues in support of the permit for the Oregon Inlet Terminal Groin. With the negotiation of the permit for the construction of the new Bonner Bridge, monitoring requirements for an expanded project area and for additional metrics have been defined. This scope has been added to the ongoing terminal groin monitoring project in anticipation of future design and planning need for the NC12 transportation corridor.
The purpose of this ongoing project (1989 to present) is to monitor and evaluate the response of a six mile stretch of shoreline just south of the terminal groin constructed to protect the bridge at the north end of Pea Island. The purpose of phase one was to establish the 'historical erosion rates' for the study area since the change in dredging operations in the inlet in 1984 and before the March 1989 storm. The continuing phases of the project consist of determining position of the shoreline from air photography every two months and evaluating the response of the shoreline in the context of the historical erosion rates.
LiDAR surveys of coastal regions over the past 15 years have generated time series of elevation data at unprecedented resolutions. For the first time, this type of data is available as a regional, multi-year time series, providing an opportunity for transition from traditional, static representation of topography to terrain abstraction as a 3D dynamic layer.To analyze dynamics of terrain in a continuous space-time domain we propose to model it using voxel models representing elevation dynamics, space-time gradients, and fastest change trajectories. The space-time cube approach is new for representation and analysis of terrain evolution. Effective visualization for this type of data has yet to be developed. Our preliminary experiments indicate the potential but need more work to be fully effective. Advanced visualization has the potential to improve our understanding and communication of complex patterns of terrain evolution at the level that will not only guide future research but also provide critical information for decision-making and on coastal impacts of climate change.
The purpose of this ongoing project (1989 to present) is to monitor and evaluate the response of a six mile stretch of shoreline just south of the terminal groin constructed to protect the bridge at the north end of Pea Island. The purpose of phase one was to establish the 'historical erosion rates' for the study area since the change in dredging operations in the inlet in 1984 and before the March 1989 storm. The continuing phases of the project consist of determining position of the shoreline from air photography every two months and evaluating the response of the shoreline in the context of the historical erosion rates.
There are three primary tasks for this proposal: 1) the establishment of a comprehensive monitoring program (along a six mile section of the coast) to determine the effectiveness of the terminal groin and revetment, 2) the analysis of the data from the monitoring program and 3) the preparation of the existing data to determine an "historical rate of erosion" for the study area shoreline in conjunction with the Department of Interior representative. This proposal is designed to provide NCDOT with a monitoring program at Oregon Inlet. This research will enable NCDOT to draw upon the existing database for the section of shoreline in the determination of the changes at the terminal groin and revetment built at Oregon Inlet.
Quantifying and understanding geomorphologic change in the coastal environment has long presented challenges to the coastal engineer, scientist and manager. Recent advances in mapping technologies (e.g., LIDAR, RTK-GPS), provide three dimensional (3D), spatial-temporal data of coastal areas with unprecedented detail and accuracy. The increasingly available spatially and temporally robust remotely sensed data products create opportunities to capture and examine the 'dynamic-state and evolutionary trends' in coastal change, the fundamental characteristic of a coastal state indicator. CSI Coastal state indicators are "a reduced set of parameters that can simply, adequately and quantitatively describe the dynamic-state and evolutionary trends of a coastal system? (Davidson et al. 2007). A well developed CSI will support fundamental management and policy decisions by communicating complex, evolving phenomena in meaningful, yet simplistic terms. This proposal seeks to 1) develop a tool set focused on merging data sets into a compatible time series to enable time series analysis, 2) quantify essential geomorphic parameters, 3) develop 3D hazard indicators (or CSIs) and 4) determine decadal volumetric change. Where possible, the influence of anthropogenic factors such as development patterns and management strategies, as well as natural forcing functions, on geomorphic change will be explored. The application of these tools will be applied to selected critical locations to illustrate their utility. This effort supports NC Sea Grant strategic initiative in Coastal Hazards in providing fundamental data analysis capabilities for the evaluation of the latest long-tem and storm related prediction methodologies for hazard identification and management strategies.
There are three primary tasks for this proposal: 1) the establishment of a comprehensive monitoring program (along a six mile section of the coast) to determine the effectiveness of the terminal groin and revetment, 2) the analysis of the data from the monitoring program and 3) the preparation of the existing data to determine an "historical rate of erosion" for the study area shoreline in conjunction with the Department of Interior representative. This proposal is designed to provide NCDOT with a monitoring program at Oregon Inlet. This research will enable NCDOT to draw upon the existing database for the section of shoreline in the determination of the changes at the terminal groin and revetment built at Oregon Inlet.
There are three primary tasks for this proposal: 1) the establishment of a comprehensive monitoring program (along a six mile section of the coast) to determine the effectiveness of the terminal groin and revetment, 2) the analysis of the data from the monitoring program and 3) the preparation of the existing data to determine an "historical rate of erosion" for the study area shoreline in conjunction with the Department of Interior representative. This proposal is designed to provide NCDOT with a monitoring program at Oregon Inlet. This research will enable NCDOT to draw upon the existing database for the section of shoreline in the determination of the changes at the terminal groin and revetment built at Oregon Inlet.
There are three primary tasks for this proposal: 1) the establishment of a comprehensive monitoring program (along a six mile section of the coast) to determine the effectiveness of the terminal groin and revetment, 2) the analysis of the data from the monitoring program and 3) the preparation of the existing data to determine an "historical rate of erosion" for the study area shoreline in conjunction with the Department of Interior representative. This proposal is designed to provide NCDOT with a monitoring program at Oregon Inlet. This research will enable NCDOT to draw upon the existing database for the section of shoreline in the determination of the changes at the terminal groin and revetment built at Oregon Inlet.
There are three primary tasks for this proposal: 1) the establishment of a comprehensive monitoring program (along a six mile section of the coast) to determine the effectiveness of the terminal groin and revetment, 2) the analysis of the data from the monitoring program and 3) the preparation of the existing data to determine an "historical rate of erosion" for the study area shoreline in conjunction with the Department of Interior representative. This proposal is designed to provide NCDOT with a monitoring program at Oregon Inlet. This research will enable NCDOT to draw upon the existing database for the section of shoreline in the determination of the changes at the terminal groin and revetment built at Oregon Inlet.