Best Available Science - FAQ's

Why did the Virginia General Assembly adopt new shoreline laws & policy?

New policies were approved in 2011 due to growing scientific evidence that shoreline hardening with bulkheads and revetments has serious adverse effects on the entire estuarine ecosystem. These impacts include reduced shallow water habitat quality, reduced sediment supply to nourish beaches and tidal wetlands, and preventing wetland migration to suitable elevations as sea level continues to rise.

Why is my City, County or Town not on the list of Locality Specific Portals?

Locality portals are available for all jurisdictions in Virginia’s Coastal Zone, as defined by the Virginia Coastal Zone Management Program.  Some of the smaller cities and most of the incorporated towns are included in the closest City or County portal.  Contact us if you cannot locate any information for your coastal locality.

Why isn't the aerial photograph in the map viewer current for my location?

The default image you see in the background is from the ESRI WorldView database. This imagery is for display purposes only because it is a uniform scale throughout the region. The data presented in the viewer and the data used in the models are NOT derived from this image.  The data are derived from the MOST RECENT image sources available. See the metadata file(s) in each locality’s Comprehensive Map Viewer under Information/Help for specific information on dates.

What do I need to view the maps? 

The interactive maps are best viewed on large tablet or desktop screens, not small mobile devices.  An internet web browser with a high-speed internet connection works best.  Make sure your browser allows pop-ups for some applications.  Silverlight is required for the sea-level rise inundation tool. GIS software is not required, but if you have it you can download GIS data to use with other applications.

Where can I find GIS data to download? 

GIS data can be downloaded from each Locality Portal for the shoreline & tidal marsh inventories plus output from the Shoreline Management Model.  The entire available shoreline & tidal marsh inventory for Virginia with all localities mapped together is also available.    

How accurate is the data and where can I view information about where the data came from?

More specific information about the original data sources is provided in each locality’s metadata.  The metadata files can be found in each locality’s Comprehensive Map Viewer under Information/Help.  The metadata is also included in the GIS Data for each locality. 

What is the Shoreline Management Model? 

It is a GIS model that determines the preferred approach for erosion control based on mapped shoreline conditions at the time of the analysis. The model follows decision tree logic to evaluate site characteristics such as bank condition, presence of tidal marshes, beaches and riparian forest, nearshore water depth, wave exposure (fetch), and the location of primary structures (e.g. homes). The model recommendations reflect the Commonwealth's preferred approach for using living shoreline treatments wherever possible to achieve adequate erosion control. See more information about the Shoreline Management Model, including the logic flow diagram and definitions of the shoreline best management practices. 

Where can I find the Tidal Marsh Inventory?

The most recent tidal marsh inventory can be viewed in each locality’s Comprehensive Map Viewer by checking the box next to Tidal Marsh under Map Contents.   The GIS data for the tidal marsh inventory can be downloaded from each Locality Portal under GIS Data Downloads.   Historic tidal marsh inventory reports are available in pdf format under each locality’s shoreline & tidal marsh inventory publications. 

Who can I contact for more information about CCRMPs?

[[wetlan-webmaster, Contact Us]] for assistance or more information about the contents, data, models, maps, or publications in the CCRMPs.  We will direct your question to the appropriate person who will get back to you as soon as possible.