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MARPLOT Software

On this sample MARPLOT map, a point object (a hospital) has been drawn on the map and a tricolored ALOHA threat zone estimate is also displayed. The Google Streets basemap is the background image of the map.MARPLOT® is the mapping program for the CAMEO® software suite, which is used widely to plan for and respond to chemical emergencies. 

MARPLOT’s easy-to-use GIS interface allows you to add objects to a map, as well as view and edit data associated with the objects.  You can choose between several background basemap images, and you can customize your map further with annotations and online layers from Web Mapping Services. You can also interact with the map in other ways, such as getting population estimates within an area.  MARPLOT can be run by itself as a general mapping program.  It can also be used interactively with programs in the CAMEO suite to display ALOHA® threat zone estimates on the map or to link map objects to database records in CAMEO Data Manager.

Downloading MARPLOT

Download MARPLOT for Windows (Version 5.1.1, Dec 2017, 176 MB EXE)

Download MARPLOT for Mac  (Version 5.1.1, Dec 2017, 283 MB DMG)

The Windows version can be run on Windows 7, Windows 8.1, and Windows 10 operating systems.  The Macintosh version can be run on Yosemite (10.10), El Capitan (10.11), Sierra (10.12), and High Sierra (10.13) operating systems.  Operating systems not listed here have not been tested and are not supported.

If you already have an older version of MARPLOT: Before installing the new MARPLOT, make a copy of your current MARPLOT Data folder and save it to a backup location. For Windows users, if you install the new MARPLOT version in the same location as your old MARPLOT 5.1 or 5.0.x version, MARPLOT will upgrade to the latest version while also keeping your current data and settings. For Mac users, there is an extra step required in the installation process. Follow the on-screen instructions in the DMG installer to upgrade your data. Note that if you're upgrading from a MARPLOT 4 series version, you need to follow additional instructions before installing the latest MARPLOT 5 version.

Learning More About MARPLOT

For a brief summary of the MARPLOT program and its capabilities, download the MARPLOT fact sheet (PDF). (2 pp, 676 KB, About PDF

The MARPLOT 5 series includes four U.S. boundaries layers and some online Web Mapping Service (WMS) layers. You can add additional object-based layers, WMS layers, and raster map images from other sources; refer to this list of national geospatial data sources for some examples. 

Significant Changes in MARPLOT Version 5.1 and 5.1.1

  • Made improvements to the auto-upgrade process to resolve rare issues some users experienced when upgrading to 5.1 (v 5.1.1)
  • Modified new layer creation process so that layers default to Individual Graphics Mode (v 5.1.1)
  • Updated U.S. Boundaries layers to 2017 data (v 5.1.1)
  • Enhanced threat zone information display in ALOHA popup notes (v 5.1.1)
  • Added ability to move objects to a different layer (if the data fields match) (v 5.1)
  • Added geodatabase files to the list of supported import file types (v 5.1)
  • Enhanced import to provide the option to import layers into folders (v 5.1)
  • Created a new MARPLOT file type (DBZ) that allows folders from the panel to be included in the export file (v 5.1)
  • Modified the new layer function to allow cloning of an existing layer (to use its settings as a template for the new layer) (v 5.1)
  • Added ability to include links to local files on the computer in popup notes and info boxes (v 5.1)
  • Switched to SQLite as the internal database structure (rather than DBF) (v 5.1)
  • Added support for Date and Date-Time fields (v 5.1)
  • Improved time zone options in the Date and Time map extra (as well as the Date/Time data fields) (v 5.1)
  • Revised basemap options, including new Esri basemaps and NOAA nautical charts (v 5.1)
  • Added enhanced support for U.S. National Grid coordinates in export and import (v 5.1)
  • Switched to a new offline basemap tile provider (v 5.1)
  • Enhanced search to allow object popup notes to be included as an option (v 5.1)
  • Added ability to show object popup notes and coordinates in the search results (and therefore also include them in the Copy Table function) (v 5.1)
  • Made improvements to the installers and the data upgrade process for existing users (v 5.1 and v 5.1.1)
  • Added enhancements for program stability and improvements for program speed (v 5.1 and v 5.1.1)
  • Made additional improvements to the program interface and fixed bugs (v 5.1 and v 5.1.1)

Getting Help

You can report software bugs or obtain additional assistance by emailing the RMP Reporting Center (, or by calling the CAMEO help desk at (703) 227-7650 on weekdays from 8 AM to 4:30 PM, Eastern Time.