The physical characteristics of the land determine the usability and potential of the property. By understanding the terrain shape and its features you can avoid properties that might be hard to work and unusable for what you want to do, such those with rough terrain and steep slopes.

On the other hand, you’ll be able to recognize certain advantages and benefits, such as ridges that are suitable for roads, water storage potential, microclimates…

When assessing for topography, we’ll look at:

  • Property size and shape
  • Topography
  • Slope

You’ll want to create a mental image of the terrain that’s surrounding the property and on the property itself. Conducting this online assessment will help you with that, even before you set foot onto the property.



    STEP 1. Locate the property on Google Earth

    • Launch the Google Earth application and zoom in on the property.

    STEP 2: Access the ‘Ruler’ tool

    • Open the ruler from the toolbar and switch to the ‘Polygon’ tab.

    STEP 3: Outline the property shape and size

    • Use the mouse to draw a polygon outlining the property shape.

    • Once you outline its shape read the area size measurement from the ruler tool.




    STEP 1. Locate the property on the Contour Map Creator website

    • Open the website and zoom in on the property.

      Note: Don’t zoom in too much as you’re trying to get the overall picture of the topography surrounding the property as well.

    STEP 2. Draw a sampling area

    • Mark a rectangle by adding two pins onto the maps.

    STEP 3. Get a contour map

    • Adjust the plot options, use level interval of 5m/15ft

    • Click ‘Get Data’, use the sampling tab.

    STEP 4. Import contour into Google Earth

    • Scroll down and press ‘Download KML file’.

    • Once the file is downloaded, open it in Google Earth.


    STEP 1. Locate the property on Google Earth

    • Launch the Google Earth application and zoom in on the property.

    • Enable the newly imported ‘Contours’ kms file in the sidebar under the places bar.

    Step 2. Assess the topography

    The elevation is indicated on topographic maps by contour lines. The spacing between contour lines determines how steep or gradual the change in elevation is in that area.


    • The closer the contour lines, the steeper the slope.


    • Contour lines forming concentric circles


    • Normally forms an hourglass shape


    • U-shaped contour lines indicate a ridge and point downstream toward lower elevation


    • V-shaped contour lines indicate a valley. The sharper the V shape, the more pronounced the valley. The tip of the V lines points toward higher elevation or upstream


    • Closed contour lines that have tick marks pointing toward low ground



    STEP 1. Locate the property on Google Earth

    • Launch the Google Earth application and zoom in on the property.

    STEP 2. Draw a straight line

    • Try to move around and zoom in to get a feel for the slope orientation so you can see what’s the best direction to slice through it.
    • (1) Click ‘Add Path’ tool on the Google Earth toolbar and (2) draw a straight line across the property.
    • (3) Once you’re finished with drawing the line, give your path a name and click ‘OK’.

    STEP 3. Show elevation profile

    • Go to the sidebar and under ‘My Places’ find the name of the path you just drew, right click on that and press ‘Show elevation profile’.

    STEP 4. Assess the slope

    • Hold your mouse over the elevation profile, it will show a red arrow on the map marking the location, and also display the height above sea level and gradient at that point.

    Type #1 Risk Assessment:

    Two things indicate you might be entering type #1 error territory when it comes to topography, namely narrow valleys and steep slopes. Narrow valleys are susceptible to flash floods and steep slopes to landslides, but the slope steepness will also determine and limit the use of the land. Any slope steeper than 18% is best left for forests.

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