Foley: Mapping and navigation are key SAR tools
We teach and practice basic navigation skills with our members several times each year, including several field exercises. In order to achieve our SAR objective we are often tasked with traveling cross country over unfamiliar mountain terrain, more often than not during the night. Join search and rescue if you want to see Colorado by headlamp! The ability to navigate by compass, read and orient a map, follow a bearing and keep track of location is basic training. Map and compass navigation is still used, although more and more field navigation is done by GPS. Every field team will have at least one GPS unit available.
Even though our team GPS units have a baseline topographic map on them we will often supply the field team with a hard copy map. We have a multi-copy library of USGS topographic maps (which are no longer being printed) that we don’t use very often. More likely, we will print the pertinent section of a map for field use utilizing mapping software. The maps will be quick printed before leaving home by one of the team leaders or we can print maps with a portable printer if our Mobile Command Vehicle has been deployed.
Recently, we have been sending a .jpg or .pdf file of the map via text or email to team members. These maps will have subject location and planned route details or other pertinent incident data embedded. This “electronic” map can be useful, but is not as good as a hard copy paper map for actual navigation. You can’t write or draw on it easily, either. Sometimes these quickly produced and electronically distributed maps are enough to get the job done.
Mapping is also extensively used by the overhead team at Incident Command (IC). Planning for a search and rescue operation relies heavily on mapping in order to be organized, efficient and effective. Initially, maps will be used to plot key information about the incident including subject location (if known), clues or last known position (LKP). IC will then determine the best location for the command post, staging area and team insertion points. A map, along with local knowledge, will be used to figure access and egress routes for field teams. If the situation is a search for a missing person a whole other level of mapping comes into play involving missing person behavior, search theory and search tactics.
Mapping was always done on what is called a map board which is simply a topo map with an acetate overlay. Special markers are used to draw on the overlay so as not to ruin the base map. This method works but some of the problems include smearing ink, hand drawn symbols and lines and the tedious method for plotting accurate coordinates. Inevitably, the area of concern was near a map corner so more than one topo map had to be cobbled together. Sharing and storing acetate overlays is problematic.
This low tech solution is still in use, but is being replaced by computer mapping software which allows map files to be manipulated, zoomed, have symbols and markers inserted at precise coordinates and are easily changed or corrected. Overlay files can be added which provide current road and trail information, ownership boundaries and other geographic data. Data can be uploaded from field team GPS units providing exact mapping of their route. Computer maps are seamless, even over large distances, and can be correlated with satellite images for even more detail. Electronic map files with all the embedded data can be easily shared, printed and filed for future reference.
One of the features of computer mapping software (or Google Earth) is the ability to view satellite images of terrain in three dimensions. This capability can give SAR managers the ability to look at terrain problems from various points of view right from the computer work station.
A recent example is the rescue of snowshoer Jeff Petersen last week. IC was able to visualize the terrain for the rescue, even though it was night time, providing the field team with valuable insight relative to their egress route after they reached Petersen. A decision was made for the team to descend the steep ridge to the north instead of retracing their track back to the summit of Berthoud Pass.
As a tools for solving SAR hurdles mapping and navigation come a long way in just the last 10 years.
Greg Foley is a member of Grand County Search and Rescue and has been a mountain rescue volunteer for 36 years. He can be reached by email at firstname.lastname@example.org. The GCSAR website can be found at grandcountySAR.com or on Facebook/GCSAR.
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