Coastal Structure and Dune Crest Inventory and Overtopping Potential

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Data Description and Usage

This viewer maps the extent of coastal engineering structures (e.g., seawalls, bulkheads, jetties, etc.) and coastal sand dune crests along the coastlines of communities in York, Cumberland, and Sagadhoc Counties, from Kittery to the Bath/Phippsburg area. The viewer also provides an analysis of the vulnerability of coastal engineering structures and coastal sand dunes to overtopping by potential storm events by displaying the relationship between the elevations of existing coastal engineering structures and protective sand dunes in reference to the 100-year (1% water level) base flood elevations (BFEs) from preliminary FEMA Flood Insurance Rate Maps. Understanding this relationship may help guide adaptive management of coastal infrastructure and the pursuit of green infrastructure approaches, such as dune restoration, in response to storms and sea level rise.

Data Disclaimer

These data are meant to help inform decisions at the local, regional, and state-level. Users must assume responsibility in determining the usability of this data for their purposes. Metadata is included for all of the downloadable layers and should be reviewed for more specifics on how these data were created. Neither the Maine Geological Survey nor the Department of Agriculture, Conservation and Forestry, nor its employees or agents: (1) make any warranty, either expressed or implied for merchantability or fitness for a particular purpose, as to the accuracy or reliability of the information shown on the map; nor are they (2) liable for any damages, including consequential damages, from using the map or the inability to use the map.

Video Tutorial

Frequently Asked Questions

The frequently asked questions provide more information about how the data layers were created, what they should be used for, usage limitations and general information on coast structure and dune crest overtopping in Maine.

Data Download

The structure and dune crest map layers can be downloaded as shapefiles for use in any GIS software to perform further spatial analysis.


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