~ Topographic Maps ~
What is a topo map?
- A Topo Map shows elevation above sea level.
- Brown colored Contour Lines are lines of equal elevation above sea level.
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Topo Maps are color coded:
BROWN: Contour Lines of Elevation
WHITE: Area of No Vegetation
GREEN: Vegetation (Forests, Grasslands)
BLUE: Water (Sea, Ocean, Lake, River, Pond)
BLACK: Man-Made Features (Buildings, Roads, Mines)
RED: Significant Manmade Features (Highway, Government Area)
PINK: Densely Populated Urban Area
Note the colors on the topo map below.
BELOW: TOPOGRAPHIC MAP OF CONCORD, MASSACHUSETTS
Click here: Maps on Line - Concord, MA
~ TOPOGRAPHIC MAP SYMBOLS ~
Click here: Take the Topo Map Symbol Quiz
Contour Lines show elevation above sea level.
Index Contour Lines are shown in bold.
QUESTION: What are the elevations of points A through D?
CHALLENGE QUESTION: Can you figure out the elevation of points A throuth J?
Surveyors use "Benchmarks" to mark elevation.
Who Creates Topo Maps? SURVEYORS
Surveyor's Rod:
Modern Surveyor - GPS Satellite
Groovy Colored Topo vs. Black and White Topo
Use the topographic map below to answer the question.
QUESTION: Throughout the area shown in the map, a thunderstorm dropped about 3 inches of rain in less than two hours. Which point on the map would be in the greatest danger of flooding?
A) point A
B) point B
C) point C
D) point D
FYI: Compared to points B,C and D, Point A is at the lowest elevation on the topographic map above. Water flows downhill due to gravity. Brown contour lines show elevation. Notice that Point A is only 18 meters above sea level. It is also on the river, and when there is rain, the banks can oveflow onto the floodplain. Points C and D are located on a hill (concentric circles) and are higher in elevation. Point B is on a tributary stream, but is higher in elevation than Point A. So, "A" is the correct answer. Point A is in the greatest danger of flooding.
Click here: How to read a Topographic Map / Activity
Click here: View another sample question on this topic
