Virginia Stormwater Act, Tiered Approach for Rural Tidewater Localities: Generation of Watershed Impervious Maps

An amendment to Virginia\u27s Stormwater Management Act was adopted to implement a tiered approach to stormwater management for rural Tidewater localities. To participate a locality is required to have a map showing the boundaries of the locality, with each watershed located partially or wholly within the locality, and the percentage of impervious cover (cover that impedes the natural infiltration of water into the soil) within each watershed. Center staff created maps indicating the initial percent of existing impervious cover present in each watershed for the Middle Peninsula Planning District (MPPDC) localities; Gloucester, Essex, King and Queen, King William, Mathews, Middlesex Counties and the Town of West Point. The watershed maps created illustrate the percent of impervious cover at the start of the tiered stormwater program; the localities are responsible for tracking any additional impervious area going forward

VIMS Marsh Migration final report + metadata sheets

Coastal marsh loss is a significant issue globally, due in part to rising sea levels and high levels of coastal human activity. Marshes have natural mechanisms to allow them to adapt to rising sea levels, however, migration across the landscape is one of those mechanisms and is frequently in conflict with human use of the shoreline. Ensuring the persistence of marshes into the future requires an understanding of where marshes are likely to migrate under sea level rise and targeting those areas for conservation and preservation activities. The goal of this project was to 1) compile existing datasets and information related to marsh migration under sea level rise-driven inundation due to forecasted climate change, topography of bay shorelines, shoreline condition (e.g., erosion rates, hardening, existing natural resources), existing wetland area and potential migration corridors, and other relevant data from around the Chesapeake Bay and 2) develop a methodology that synthesizes the information in a format that can be used to assist with marsh conservation and restoration decisions under multiple sea level rise scenarios (see associated report). This dataset is the resulting data from the methodology development

Impact Assessment and Management Challenges of Key Rural Human Health Infrastructure Under Sea Level Rise

Accelerating sea level rise in Virginia, United States, will significantly increase the flooding threat to low-lying roads, residences, and critical infrastructure as well as raise the water table, allowing saltwater intrusion into well water and threatening the function of septic fields. Although most of the adaptation work in Virginia has focused on urban economic centers, the majority of the coastline is rural and faces different threats and opportunities to address them compared to urban areas due to their reduced economic assets and their reliance on private infrastructure. In this case study, we assess the potential for geospatially quantifying impact to septic systems and adjacent water ways due to sea level rise. The case study found that the data necessary to reliably quantify these impacts on a state-wide scale are lacking and collection of that information needs to be prioritized given the potential for extensive sea level impacts

Synthesis of Shoreline, Sea Level Rise, and Marsh Migration Data for Wetland Restoration Targeting Final Report

Coastal marsh loss is a significant issue globally, due in part to rising sea levels and high levels of coastal human activity. Marshes have natural mechanisms to allow them to adapt to rising sea levels, however, migration across the landscape is one of those mechanisms and is frequently in conflict with human use of the shoreline. Ensuring the persistence of marshes into the future requires an understanding of where marshes are likely to migrate under sea level rise and targeting those areas for conservation and preservation activities. The goal of this project was to 1) compile existing datasets and information related to marsh migration under sea level rise-driven inundation due to forecasted climate change, topography of bay shorelines, shoreline condition (e.g., erosion rates, hardening, existing natural resources), existing wetland area and potential migration corridors, and other relevant data from around the Chesapeake Bay and 2) develop a methodology that synthesizes the information in a format that can be used to assist with marsh conservation and restoration decisions under multiple sea level rise scenarios (see associated report). This dataset is the resulting data from the methodology development

New Guidance to Build Resiliency and Mitigate for Sea Level Rise as Elements of the Chesapeake Bay Preservation Act

The Center for Coastal Resources Management (CCRM), Virginia Institute of Marine Science (VIMS), worked in collaboration with the Virginia Department of Environmental Quality (DEQ) and the Virginia Coastal Policy Center (VCPC) to develop guidance to inform the implementation of Chesapeake Bay Preservation Act (CBPA) regulations promulgated in 2021. The 2021 regulations added provisions to require local governments to consider climate changes, specifically flooding, sea level rise and storms, and the preservation of mature trees in the administration of the CBPA program. Specifically, CCRM developed analytical data using criteria specified in the CBPA regulations, of the National Oceanic and Atmospheric Administration (NOAA) intermediate high sea level rise curve for the year 2050, to project future shoreline and Resource Protection Area (RPA) features

A geospatial modeling approach to assess site suitability of living shorelines and emphasize best shoreline management practices

The Shoreline Management Model (SMM) is a novel geospatial approach used to assess conditions along a shoreline, and recommend best management practices for defended and undefended shorelines. The SMM models available spatial data in order to identify areas where the use of living shorelines would be suitable to address shoreline erosion. The model was developed to support and inform decision-making by shoreline managers responsible for management of shoreline resources, shorefront property owners, and tidal habitat restoration actions. Recommended erosion control strategies are based on scientific knowledge of how shorelines respond to natural conditions and anthropogenic measures used to stabilize shorelines. The SMM uses input variables representing current conditions and recommends a strategy that falls into one of three general categories: living shorelines, traditional approaches, and special considerations. Areas of special consideration are areas where the model may not be able to provide an appropriate recommendation due to ecological, geological, or highly developed conditions. These areas are given recommendations that include the instruction to seek expert advice. Data required to run the model include presence of tidal marsh, beach, submerged aquatic vegetation (SAV), riparian land cover, bank height, nearshore bathymetry, fetch, and shoreline erosion control structures. The model has been calibrated and validated along Virginia’s Chesapeake Bay shoreline, USA. The model results are largely consistent with field recommendations (i.e., shoreline management recommendations made by scientists based on on-site observations during shoreline evaluation visits). The SMM performed with an overall accuracy of 82.5%. The SMM is exportable; the model code can be adapted to other systems. This geospatial model provides a robust screening tool for local and state governments, coastal and environmental planners and engineers, as well as property owners, when considering best management practices, including living shorelines as an alternative for erosion control

Summary Tables: City of Poquoson, Virginia Shoreline Inventory Report

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes)

City of Poquoson, Virginia Shoreline Inventory Report Methods and Guidelines

The data inventory developed for the Shoreline Inventory is based on a three tiered shoreline assessment approach. In most cases this assessment characterizes conditions that can be observed from a small boat navigating along the shoreline. The three tiered shoreline assessment approach divides the shorezone into three regions: the immediate riparian zone, evaluated for land use the bank, evaluated for height, stability, cover and natural protection the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes. The 2001 Inventory for the City of Poquoson was updated using on-screen, digitizing techniques in ArcMap® v10.0 while viewing conditions observed in 2012 online Bing high resolution oblique imagery and 2011 imagery from the Virginia Base Mapping Program (VBMP). These data sources allowed the inventory to be updated without additional field work. Three GIS shapefiles are developed. The first describes land use and bank conditions (poq_lubc_2013). The second reports shoreline structures that are described as arcs or lines (poq_sstru_2013). The final shapefile includes all structures that are represented as points (poq_astru_2013). The shapefiles use a shoreline basemap updated in-house from the VBMP2011 high resolution digital terrain model. The shoreline is re-coded to reflect features and attributes observed. The metadata file accompanies the shapefiles and defines attribute accuracy, data development, and any use restrictions that pertain to dat

Summary Tables: York County, Virginia Shoreline Inventory Report

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes)