WETMAAP Technique 2
Red River - Element 1

Technique 2: Manual GIS
Element 1: Making Feature Overlays

Materials:

1:24,000 scale 1980/1992 Shreveport East, LA, USGS Topographic Quadrangles

(3) 11"x 17" clear film overlay

drafting tape

Colored marker pens: Blue, Black, Green

Exercise:

1. Use 1:24,000 scale 1980/1992 Shreveport East, LA, USGS Topographic Quadrangles

2. Use clear film 11"x 17"overlay.

3. Tape clear film overlay on top of 1:24,000 scale map. Tape at the top edge.

4. Use the Blue pen.

5. Use the Blue pen to make four "corner marks" (tick mark _) on the overlay, one at each corner of the study site.

6. Trace the river banks of the Red River in Blue on the overlay.

7. At the bottom of the overlay (in blue) draw a short horizontal line and label beside it "1992 River Channel."

Hint: Use of a symbol with a short description beside it is a "key," or means of identifying selected features.

8. Remove the "1992 River Channel" overlay.

9. Use a second 11"x 17"clear film overlay.

10. Tape clear film overlay on top of 1:24,000 scale map. Tape at top edge.

11. Use the Black pen.

12. Use the Black pen to make four "corner marks" (tick mark) on the overlay, one at each corner of the study site.

13. Trace the Caddo Parish/Bossier Parish boundary with a dashed Black line on the overlay.

14. At the bottom (in black) draw a short horizontal line the same length as the black line and label it "Parish Boundary.”"

15. Remove the "Parish Boundary" overlay.

16. Use the third 11" x 17" clear film overlay.

17. Tape clear film overlay on top of the 1:24,000 scale map. Tape the top edge.

18. Use the Green pen.

19. Use the Green pen to make four "corner marks" (tick mark _) on the overlay, one at each corner of the study site.

20. Outline all woodland vegetation areas in Green on the overlay.

21. At the bottom (in green) make a small polygon and label it "Woodland" Do not remove this overlay.

Hint: Combining several single "key" items creates a "legend." Every map should have a legend

22. Tape the "1992 River Channel" and "Parish Boundary" overlays one on top of each other, over the "Woodland" overlay. Use the four corner marks to line-up ("register") the overlays on top of each other.

Hint: Tape one overlay at the bottom edge and the other overlay at the left or right edge. By attaching the overlays at opposite edges, you can flip the overlays up and down in various alignment. You have created a manual GIS.