Navigating with a Map and Compass

Introduction

            Navigating with a topographic map and a compass requires a lot of preparation and accurate measurements. Today people have the benefit of technology such as the GPS to depend on for navigation; however sophisticated instruments such as this cannot always be relied on. After creating the navigation maps of the priory from last week, the class went to visit the Priory site on the south side of Eau Claire to put the maps to use. The instructor gave each group of three a series of 5 waypoints in UTM coordinates to manually plot on the maps. Each group had to pick the two best maps between the members to use for the navigation exercise—one with the 2 meter contour line interval and the other displaying the 5 meter contour line interval. This report will include a breakdown of the methods and what parts of the maps worked and what parts did not.

Methodology

            One of the most important parts of navigating is making sure the grid coordinates on the maps are in UTM so that distance can be measured when doing the exercise. The study gave the class an opportunity to work in groups of three and navigate to five specific locations in the Priory using a map and compass. This project is laid out in the following methods: gather the navigating materials, plot the points on the map, find compass bearings between each set of waypoints, measure distance between each point, discuss and assign the roles for each group member in the field, go out and collect punches at each waypoint with the group.

            The materials needed in the navigation activity include the following: magnetic compass, 5 meter contour lined map, 2 meter contour lined map, punch card, and the list of waypoints for the assigned course. Since the points provided by the instructor are in UTM, it is essential to have the grid coordinates in UTM on the navigation map. One of the maps that the group picked did not have these coordinates making it useless on the day of the activity. Fortunately all of the other groups had UTM coordinates on their grid and my group was given a usable map for the navigation exercise. The class was also given a refresher on how to use a magnetic compass for navigating in the field.

            Once the materials are gathered for the navigation exercise, the waypoints can be plotted on the map according to their given UTM coordinates (Figure 1). The instructor created 3 courses around the Priory property for each group to go out and punch in at 5 specific locations throughout study area. My group was assigned course 2, which included trekking over different levels of terrain between each point. Since the map that the group used had a 20 meter grid, each member checked to make sure that the points were accurate enough before moving on to the next step.

Figure 1: Plotting Course 2 Points on the Navigation Map

            The third method is to find compass bearings between each set of waypoints on the navigation map. Straight lines were drawn between the points so that the compass can be aligned in the exact direction of the next point on the list. Using the magnetic compass, one can take the direction of travel arrow and align it on the line between a set of points. For example, we took the compass and placed it on the map aligning it with the line between the starting point and the first point on course 2. This method was done for each plotted point on the map. We then had to move the compass house with degree dial until the “N”, which indicates north, points to the top of the navigation map. The top of the map for this study is assumed to be true north and is closely lined up with the tilted vertical gridlines. Once the “N” is pointed to top of the map, the group can look at the index line where it says “read bearing here” and record it so that it can be used to find the next point. These bearings will help us in the field once we get to a specific spot by showing us the direction that we need to face to reach the next point.

            The fourth method is to measure the distance between each point on the map using the scale bar and a piece of paper. We discovered that one of our group members has a consistent pace count of 65 for every 100 meters. Knowing the distances between each point will give us an idea how far we will need to go before looking for the landmark point on our list. The deep snow and rough terrain, which includes steep hills and thick forests, may throw off the consistent pace count making it necessary to add 15-20 steps for every 100 meters.

            The fifth method is designating the roles for each group member while navigating in the field. We had one person (me) manipulate and hold the compass according to the bearings and face in the direction of the point on the map. Since there were many steep hills and fallen trees in the way of each point, a second person (Hannah) was responsible for moving to the landmark in the direction dictated by the person holding the compass (Figure 2). This allowed for each trek between the set of points to be done in segments and ensure better accuracy in the direction of travel. Once our group member reached the landmark in the direction of the compass holder, the other person (Kory) did the pace count to that spot. Kory would add to his pace count until the group reached marker of our next point (Figure 3).

Figure 2: Group Member moving to designated landmark in the distance (dictated by compass holder)

Figure 3: One of the Markers in Course 2

            The last method is to go out with the group to navigate and collect punches at each point on course 2. This required good communication between the members to ensure that we were heading in the right direction and finding ways to overcome obstacles along the way. Both the 2 meter contour and 5 meter contour line maps were utilized in this activity because each included features that were helpful in navigating to the destination points. One map had an aerial basemap under the lines, which made it easy to tell where we were on the property of the Priory and whether or not we were getting close to a plotted point.

Discussion

            Being able to navigate with a topographic map and compass reduces the dependence on technology to do it for us. Although this navigation method is not as easy as it looks, we found that it is fairly accurate and led us to find the points on the map without too many issues. The two meter contour line map was an advantage for us in this exercise because it showed us the type of terrain in our direction of travel. Not only could we see that there was a steep hill in front of us, but the map also confirmed a steep change in elevation ahead. The aerial basemap was also beneficial to finding the location of these points by helping us see if we had to go through a dense forest of evergreen trees or around a large pond. The other advantage of our preparation before going out to field was plotting the distances we needed to travel in 100 meter intervals. This gave us an idea of how far it was to the next point while taking into consideration the pace count of the walker.

            Although there are many advantages to our navigation maps in this exercise, one disadvantage is the difficulty of being able to read the map with the 2 meter contour lines because it also included the aerial map. The next navigation map should have a more transparent the aerial map so that it is easier for even a non-geographer to read and navigate with. Another obstacle we faced while locating the points was trying to maneuver around the ponds near the freeway. Since this land feature was in the direct path of one of our points, we had to go around it and estimate Kory’s pace count once we got to the other side. The last disadvantage was our attempt to move in a straight line through the deep snow and thick forest. Even though it is winter and the trees are not filled with much vegetation, there are many fallen down logs and small trees that got in our way. We were able to overcome this by designating a visible landmark in the distance that connected with our path and have that as a meeting point before moving on.

Conclusion

            The goal of this activity is to be able to navigate using a topographic map and compass at the Priory property in Eau Claire. Although there are faster methods to navigating around an area, this method avoids relying on technology while still being fairly accurate. I have taken a lot out of this experience by learning how to use a magnetic compass and map to reach a specific destination on a large parcel of land.