How to Dig a Wet Trench

Trenches are used in irrigation to positively affect landscaping and to allow water to escape from a property when heavy rain or flooding occurs. Trenches built for the latter purpose are called French drains. Trenches for plants and gardens are very simple and shallow, typically covering a short circumference around the area you intend to water. French drains, however, are more expansive, deeper and take more work because they serve a different purpose than normal trenches. By creating a French drain, or trench with an underlying pipe that re-directs water, you protect the top layer of soil. If your lawn is over-saturated, it can potentially damage this top layer of soil, flood gardens, planted trees and shrubs, and even flood the home.

Things You'll Need

• Shovel
• 6-feet-long, 4-inch by 4-inch piece of wood
• Gloves
• Gravel
• Perforated PVC drainage pipe
• Sod

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Instructions

1. • 1

     Dig a 6-inch-wide, 24-inch-deep trench extending from the highest part of the property to the lowest, in a U-shaped form. The bottom of the trench can be flat or contoured to the property's natural contours, like fences.

   • 2

     Compact soil at the bottom of the trench with a 4-inch by 4-inch piece of wood.

   • 3

     Pour 2 inches of gravel on top of the trench soil.

   • 4

     Lay perforated PVC pipe throughout the trench. Keep the part of the pipe with the holes facing down.

   • 5

     Cover the PVC pipe with a layer of gravel extending an inch short of the surrounding soil.

   • 6

     Cover the gravel with a thin lining of sod.