Surveyors, Snowshoes, and a Rugged PDA!

You don’t usually pack snowshoes for a survey project, but John Stewart and his 14-person crew had to when they performed a biological inventory in waist-high snow on the north face of Utah’s Monroe Mountain.

Stewart and crew, working for Cirrus Ecological Solutions, were on the 11,000-foot-high mountain in Fishlake National Forest to perform surveys that would be used by the U.S. Forest Service to determine whether and how to authorize 120 miles of seismic oil and gas explorations near Henries Hollow. Seismic studies involve setting off controlled explosives and monitoring the resulting shock waves with geophones strung out over miles of terrain, and the Forest Service wanted to avoid disturbing sensitive species where those lines crossed public lands. As part of their project, Stewart and his crew laid out transects for their biological survey based on these seismic lines.

Preparing for the survey

Fig. 1: The Archer Field PC with a Universal Extended Cap.

The crew used eight Juniper Systems Archer Field PCs (junipersys.com), each equipped with a Universal Extended Cap housing a GPS receiver (Fig. 1). These Windows Mobile 5 devices were used to inventory bird species designated "sensitive" by the U.S. Forest Service. To prepare for the survey, predetermined "sampling points" (i.e., specific locations where the data would be collected) were laid out along the survey transects using ESRI ArcGIS 9.2 (esri.com) on Cirrus’ office computer. Each of the Field PCs used on the project was loaded with ESRI’s ArcPad software, which would be used for navigation during the survey and to record inventory data.

For navigation purposes, a base map of USGS 7.5 minute topographic quadrangles was overlaid with shape files of area roads, survey transects, and existing Forest Service survey data. All this was loaded into the GPS-equipped Field PCs running ArcPad before the research crews were deployed.

GPS capability was essential to the survey. Without it, field crews would have to rely on map and compass skills, and likely spend more time finding the sampling point locations. Having topo maps displayed was also crucial to efficiently navigate around complex and hazardous terrain. With GPS, field crew members could eliminate the guess work and navigate to where they were supposed to be quickly and safely.

Helicopters and snow shoes

Fig. 2: Standard equipment for the team included a backpack, snow shoes, radio, tape player, and a Field PC.

Accessing the survey points was difficult because the deep snow pack at the higher elevations being surveyed made many of the roads impassable. To meet schedules, the team used a helicopter to transport the surveyors to the inaccessible areas. Each morning, this aerial "taxi service" dropped the crew off in pairs at the tops of the mountains, along with their backpacks, snow shoes, and other equipment (Fig. 2). At the end of the day, field crews used GPS to find the pick-up zones.

The helicopters were equipped with GPS navigation systems, but the pilots didn’t have project information loaded into them. Instead, Cirrus personnel used their Field PCs to guide the helicopter pilot using ArcPad’s navigation features.

Although a helicopter ferried field crews to the beginning of the survey lines atop Monroe Mountain, the surveyors had to navigate to individual sampling points on their own. That’s where the snowshoes—and the PDAs—came into play.