WETMAAP Skill 2
Lake Pontchartrain - Martello Castle Element 3

Extension
Skill 2: Scale Determination
Element 3: Linear Measurement of Change

Materials:

        1:24,000 scale Martello Castle Topographic Map

        1978 NWI Map

        1988 NWI Map

        1995 Aerial Photograph

        ruler

        calculator

        Reference Manual

Exercise: Measure the change in width of the MRGO

1. Find what you consider to be the widest area of the MRGO on the 1995 aerial photograph.

2. Identify two points on the opposite sides of the MRGO channel at it widest area. Measure distance across the cannel.

3. Identify (as best as you can) two points on opposite sides of the channel in the vicinity of those identified on the 1995  aerial photo, the NWI maps, and the topographic map. Measure (as best as you can), the distance across the channel:

                        Distance in Inches Distance in Map Feet

                        Measurement with ruler

                Hint: The scale of the 1995 aerial photo must be determined using Skill 2, Element 2.

        4. Has the width of the MRGO increased over time?

        5. If the MRGO was originally dredged at 500 feet wide,

                a. How many feet has it increased in width?

                b. What is the percent increase?