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What you need:
  • Transit level
  • Assistant
  • Spirit level
  • Pad of paper
  • Pencil
When used properly, transit levels provide invaluable information on the lay of the land. Before installing pathways, lawns, or planting beds, it's important to identify any low spots that may cause problems with drainage. The first step in using a transit level is setting up the tripod. The spot that the tripod is set up on should have an unobstructed view of all the points you wish to grade. The platform on top of the tripod should be at about the same height as your sternum.
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Make sure the tripod is level before attaching the transit level. Place a small spirit level on the platform on top of the tripod. Adjust the height of the legs until the platform is level.
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Once the tripod is level, place the transit level on the platform. There is a handle under the platform that screws into the bottom of the level. Thread the handle into the base of the transit level and tighten it.
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In order to get reliable data from a transit level, it must be perfectly level. There is a scale at the base of the level that is used to judge the position of the level expressed in degrees. The level must be leveled at 0 degrees and at 90 degrees for the best accuracy.
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In this example, there is a question as to which direction water will drain off of a road. By taking measurements on the left side, the center, and the right side of the road the grade can be determined. This is what you see when you look through the transit level. The value in the center of the crosshairs, in this case 44 inches, is recorded.
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Next a measurement is taken from the center of the road.
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The last measurement is taken from the far right side of the road. The three measurements taken were 44, 44-5/8, and 46-3/4. The higher the number, the lower the point is. By using these measurements, it's determined that water will run from the left side across the center and off the right side. The same process can be used to determine the amount of rise or drop on any piece of land.