Written by: Christopher Freeman, RPLS #5701

I initially was referred to a Troop 1171 Scout Leader by Chapter 5 member Stephanie Beckham. She knew the Leader, and the Troop had utilized her property in Limestone County several times for camping and other Scout activities. I arranged to attend a Troop meeting in January to discuss Surveying, demonstrate the use of survey instruments, discuss career opportunities, and offer to assist in a Survey Merit Badge activity if there was interest. By the end of the meeting, 20 Scouts signed up for the Survey Merit Badge.

The exercise was scheduled for mid February. The Scouts arrived on Friday night and set up camp. Two main exercises were to be completed: 1.) a closed traverse in which the Scouts measure the sides and interior angles of a polygon, and 2.) a closed level loop assuming an elevation of one of the aforementioned traverse points.

The exercise commenced at approximately 10:00 a.m. under relatively calm but cold and cloudy conditions, with intermittent light mist. I met the 20 Scouts and 4 adult leaders on site, a clearing surrounded by timber and thick underbrush. The group was divided into 4 survey teams. Instructions were given on field book note keeping, setting up the instruments, turning and recording angles, performing rodman duties with the prism poles for measuring the backsight and foresight distances or holding the level rod during the bench loop. The team utilized a Topcon GTS-226 electronic Total Station and a Sokkia C3i Differential Level.

For the traverse exercise, the teams each turned an interior angle and measured two legs of the polygon from their observation station. A compass reading was taken at the first setup to provide a Basis of Bearing. After moving up to the next station, the new team checked the distance recorded in the field books (donated by long-time TSPS partner Geomatic Resources) by the previous team to ensure no blunder had been recorded. When a team was not actively involved with the measuring at a particular station, they observed the working team, recorded results, and entered sketches in their notes. 

At one point during the chilly morning, firewood was gathered and a fire started, bringing welcome heat to the survey teams. The closed traverse was completed with a Linear Error of Closure of 0.03 feet. The perimeter distance measured was 611.92 feet. The precision for the survey was 1/20,000, a decent survey for first-time surveyors. The area measured was 22,293 square feet.

Upon completion of the traverse exercise, the teams switched gears to run a closed bench loop. After a quick lesson on how to set up the instrument, focusing, reading the rod, and keeping level notes, the teams were ready to go.  Assuming an elevation of 100.00 at Point #1, the teams took turns reading the level rod backsight and foresight readings, and recorded the observations in their field books. Some teams had other team members check the rod reading before finalizing their reading. The teams turned on each of the points, returning to the starting station at Point #1. After a quick tally with the calculator, the results showed that the loop closed flat with the original starting elevation. How about that?! Looks like we may have some future survey talent out here! The Scouts were smart and inquisitive, as well as quick learners.