South Carolina Intertidal Oyster Reef Mapping

DOQQQ Imagery and Oyster Reef Areas

This dataset contains mapped boundaries of intertidal oyster reefs and washed shell deposits found along the SC coast. Reefs were mapped through a combination of automated and manual techniques using 4-band (blue, green, red, near-infrared) digital orthophotos with a theoretical ground resolution of 0. 25 meters. These photos were taken from 2003- 2006 and can be downloaded. The project area covered those sections of the SC coastal zone where oysters had historically been mapped by the SC Department of Natural Resources (SCDNR) in the 1980's. The area spans 122 USGS quarter quadrangles (DOQQs).

Sixty of the mapped DOQQs were ground-truthed by boat to assess accuracy. The remaining DOQQs are currently being verified through 2006-2008 photos taken from low-altitude helicopter flights (see photo below). The initial mapping process has met the overall minimum accuracy requirements of the project (80% correct classification) and was completed through a joint effort between Photo Science Inc. and SCDNR. However, final edits and improvements are still in progress through SCDNR, and this dataset will be updated.

Oyster Strata

A link is listed below for a table that lists accuracy and editing status data by DOQQ. Accuracy scores listed were calculated prior to SCDNR final edits, so these scores should be considered to be the minimum level of accuracy for the edited DOQQs. Areas covered and analyzed by low-altitude helicopter photographs can be considered to have the highest degree of accuracy. DOQQs that have not been edited by SCDNR should be used with caution. Due to variations in image quality and visibility of oysters, some localized areas may not be as accurate as reported values. In particular, some of the oyster flats with sparse or patchy oyster coverage were difficult to map. Instructions and links are provided below for access to the data and associated metadata.

Project Partners include:

Geographic Coordinate System

UTM, Zone 17, Meters, Datum NAD83

File Format Available

ESRI ArcGIS v9.2 Personal GeoDatabase


ArcIMS Service

Accuracy and Editing Status

Available data set is currently provisional and will be updated.

Metadata for this project is available:

Viewing Oyster Bed Data

To view the GIS data, you will need computer mapping software. For users without GIS desktop software, a free desktop viewer from ESRI is available, ArcGIS Explorer. The Resource Center for ArcGIS Explorer from ESIR provides tutorials, Online Help, forum, and related documentation. The TatukGIS Viewer is a free viewer available from TatukGIS.

For other software programs, please consult your particular software's help to determine compatibility with this format and any required software updates and/or plugins.

Download Available Oyster Bed Data

Data is available for download at no cost from DNR's ftp site. Last updated July 2011.

DOQQQ imagery is available at the following link, DOQQQ Imagery.

Access Oyster Bed Data through GIS Service

Data can be accessed through a GIS service: