Erosion of Coastal Beaches and Dunes During the Highest Water Level on Record in Southern Maine, USA (Data Files)

Authors

Katelyn DeWater, University of New EnglandFollow
Matthew Pittsley, University of New EnglandFollow
Johanna Birchem, University of New EnglandFollow
Ruth Ellis, University of New EnglandFollow
Tyler Janik, University of New EnglandFollow
Paige-Marie Merrill, University of New EnglandFollow
William Kochtitzky, University of New EnglandFollow

Document Type

Data

Publication Date

Winter 2-25-2025

Abstract

Maine experienced its highest water level ever recorded on January 13, 2024, just two days after another winter storm with an even higher storm surge on a smaller tide. In this study, we aimed to quantify the impact of these storms along five shorelines in York County, Goose Rocks Beach in Kennebunkport, Fortunes Rocks, Middle, Biddeford Pool, and Hills, in Biddeford, and Camp Ellis, Ferry, and Bayview beaches in Saco. We used aerial and unoccupied aerial vehicle (UAV/drone) imagery to analyze the changes in area and volume of dunes and sand along the beaches before, after, and during recovery due to the storms. We hand-digitized the dunes in QGIS for each orthomosaic in the dataset from 2021 to 2024. For Saco, we used the State of Maine South Coast/Coastal Orthoimagery from June 2021 as the baseline imagery. All other orthoimagery (both baseline and post-storm surveys) was generated from UAV surveys collected by authors in 2023 and 2024. Dunes were attributed to either primary, sparse, patchy, or planted vegetation based on the optical density of dune grasses; we also classified dunes by structures along the beach, such as cored by seawalls or riprap. To quantify changes in dune volume, digital elevation models (DEMs) generated from the 2023 and 2024 UAV surveys were used along with dune polygons in zonal statistics. The dune geopackage layer is available here (orthomosaics, DEMs, processing reports, and supplementary tables are available under Additional Files):

• ‘Dunes’ contains digitized dunes for each survey at the beaches: Bayview, Saco, Camp Ellis, Hills, Fortunes, and Goose Rocks, ME for their respective survey dates.

Comments

The main file is a file of geopackage dune data. Both orthoimagery and DEMs (all are .tif) from each beach and survey period, along with Metashape reports from the processing of this imagery and supplementary tables detailing UAV imagery, are available below under Additional Files. The geopackage (.gpkg) and .tif files can be viewed in any GIS software such as QGIS or ArcGIS. Files are projected in UTM 19N (EPSG: 32619).

Attributes (in dune geopackage):

• Beach Name: Bayview, Saco, Camp Ellis, Hills, Fortunes, GRB

• Area (m2)

• Vegetation Type: Primary (dense vegetation over an area that is between beach and upland), Sparse (vegetation over an area either in front of primary vegetation or other coastline features that has a low vegetation density, appears like tufts of grass scattered with noticeable sand area in between), Patchy (has dense patches scattered throughout with sandy areas, mostly seen on GRB where it is difficult to differentiate between primary and sparse vegetation), Planted (areas that have had dune grasses planted)

• Coastline Type: Dune or Dune Cored (with seawall or riprap behind or through the dune)

• Specific Coastline Type: Dune, Behind Riprap (full area of dune lays behind a riprap wall), Riprap Cored (riprap in front of, through all of, or through a section of polygon), Behind Seawall (full area of dune lays behind a seawall), Seawall Cored (seawall in front of, through all of, or through a section of polygon)

• Date: Contains date of survey for each polygon (YYYYMMDD or YYYY, depending on the beach and survey).

Details for Additional Files:

Files include all orthoimagery and DEMs for each beach date and survey period. All imagery is in meters and was processed in Agisoft Metashap Professional; processing reports are also available here. The supplementary table (.xlsx) file includes additional information for imagery including resolution and tide information at the time of collection.

Recommended Citation

DeWater, Katelyn; Pittsley, Matthew; Birchem, Johanna; Ellis, Ruth; Janik, Tyler; Merrill, Paige-Marie; and Kochtitzky, William, "Erosion of Coastal Beaches and Dunes During the Highest Water Level on Record in Southern Maine, USA (Data Files)" (2025). Geographic Information Systems Data Projects. 3.
https://dune.une.edu/gis_data/3