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Watering A Slope: Not To An Uphill Battle

This article explains how to measure slope. A landscape with a slope of over 10% will require special planning to avoid an unwanted runoff. A way around this is to create flat terraces held in place by retaining walls. You will need to set low precipitation devices at the correct angle for areas with no structural changes. Click here to learn more about how to install an irrigation spray or rotor

Supplies Needed To Measure A Sloped Terrain:

  • Spirit or line level
  • String
  • Tape measure
  • Stake or screwdriver
  • Assistant (it is much easier with an additional set of hands)

Steps To Learn How To Measure Slope:

  1. Attach a string to either a stake or a screwdriver.
  2. At the highest point of the ground plant the stake with the string (or screwdriver) into the soil. If you have an assistant they can walk to the bottom of the slope with the remainder of the string.
  3. Hold the string tight and level by using a line level.
  4. The leftover string will fall towards the ground and attach a weight to the string to form a solid 90-degree angle.
  5. Measure the length of the string from the high point to the assistant’s hands. Then measure the height from the string in the assistant’s hands to the ground.
  6. To find the percentage of slope simply divide the rise (the measured height) by the run (the measured length) and multiply by 100.
  7. If the measurement is less than 10% there is no need to show it on your design plan.
  8. If it is over 10% you can show this on your design plan by shading it in with diagonal lines.
  9. Large sloped areas can be measured by picking a smaller (more manageable) area by eye that has the same general angle and using the same methods as shown to determine the slope.

Determine The Percentage Of Slope:

Use this equation to learn how to measure slope.

Divide the measure of height by the measure of the length and multiply by 100.

Example above: 2 รท 14 x 100 = 14.3%