Data Downloads

While browsing or searching through the DataMIL Catalog, a "Download" button will be displayed next to each entry that has an attached data file. These files are usually small in size (less than 50 MB) and be downloaded easily.Metadata entries for large datasets will have other types of buttons to direct you to locations for data download.

Most data served from DataMIL are distributed as compressed, archived files in the .7z format. These are analogous to .zip files but are created with the 7zip program instead of WinZip. 7zip differs from WinZip in that it is more efficient, supported on multiple platforms (Windows, Mac, Linux), and free and open source. Download 7zip now!.

Some data sets are too large to create single data files for easy downloads. For the Delaware aerial imagery as well as the recent statewide LIDAR DEM data, individual tiles (1.7km x 1.7km) were created to distribute the final products. The Tiled Data Distribution site offers a Google Maps-based interface that allows you to download this data for any location within Delaware with a single click.

All tiled data served from DataMIL are compressed using 7zip. (More info about 7zip on the Tiled Data Distribution site.) Each 7z archive contains multiple files associated with that dataset. The table below lists the basic specifications for each data set distributed piecewise as tiles.

The Map Production Lab is where you can browse all of the layers of the Delaware Spatial Data Framework. On the MapLab interface, you'll see a button labeled "Extract Data." This tool will extract any vector-based data layers visible in the MapLab. The extraction works by clipping all visible vector layers to the current map extent, converting the layers to shapefiles, zipping all of the files into one WinZip archive for download.

The speed of the process depends on the number and type of layers included but usually takes 10 - 20 seconds to complete.

All of the data displayed on the DataMIL MapLab, as well as historic aerial imagery, are available via web mapping services. DataMIL supports ArcIMS Image and Feature services and WMS services. ArcIMS Feature services include only vector data while ArcIMS Image and WMS services include both vector and raster. For WMS, DataMIL recommends using version 1.1.1 for all requests.

The "datamil_gos" service contains nearly all data sets as displayed in the MapLab and is our recommended service when needed a map with multiple layers, or a map containing both vector and raster data. The table below lists all services and layer names served by DataMIL.