Table of Contents
What do the numbers mean on a lake map?
These lines show you how far points come out into the main lake or cove, where humps or ridges are in the main lake and define the main and secondary creek channels. The contour lines are usually indicated in feet, at intervals of 5 to 10 feet apart. Some maps will have elevation numbers.
Where do you find walleye on a contour map?
If you study a lake map, you’ll see spots where contour lines run together. These are steep drops — in some cases almost an underwater wall. Walleyes follow these steep dropoffs in their daily movements.
How do you read water on a topographic map?
A general rule of thumb is that water flow is perpendicular to contour lines. In the case of the isolated hill, water flows down on all sides of the hill. Water flows from the top of the saddle or ridge, down each side in the same way water flows down each side of a garden wall (See arrow on Figure E-2).
How do I find a topographic map in Minnesota?
Find Minnesota topo maps and topographic map data by clicking on the interactive map or searching for maps by place name and feature type. If you know the county in Minnesota where the topographical feature is located, then click on the county in the list above. Every map in the state of Minnesota is printable in full color topos.
What are the features added to a lake map?
Rivers, roads, landmarks, and other geographic features are added to the map, and the map is edited to ensure accuracy. The lake’s surface area, littoral area (area 15 feet or less in depth), volume, mean depth, and shoreline length are calculated.
How is a lake map made?
Once the contours are drawn, the map is captured and stored electronically, or digitized. For lakes sounded using the GPS method, the data collected by the boat during sounding is combined with the data collected from the base station, resulting in data that provides accurate locations.
How do you map a large lake?
For lakes over 2,000 acres, the line of sight technique may be inaccurate due to the inability to see the shoreline across large bodies of water, and dangerous depending on weather conditions. Therefore, a larger boat and GPS equipment are used to map large lakes. For this method, transects are run based on latitude and longitude readings.