How to Get Clay Soil to Drain

Clay soil is very fine and compacts easily, blocking water movement.

Clay soil is composed of fine particles which are easily compacted and waterlogged. High traffic areas are especially susceptible to compaction and flooding. Even if topsoil is aerated and porous, hardpan, an extremely dense and compacted layer of earth beneath topsoil, exists in some clay rich regions. This layer can prevent water from draining. The removal of excess water does not require a complex drainage system. Provide waterlogged soils with much needed underground reservoirs by creating French drains or soakaways.

Things You'll Need

• Garden spade
• Geotextile (fabric liner)
• Broken brick, stone or gravel
• Drainage pipe

Instructions

1. Locate an area of your lawn or garden prone to flooding.

2. Remove the turf or sod.

3. Dig a hole that is 6 feet deep and 3-by-3 feet wide.

4. Line the hole with geotextile fabric liner.

5. Fill the hole with 3 feet of gravel or broken masonry.

6. Fold the fabric over the gravel.

7. Wedge a drainage pipe into the wall of the trench. Angle the pipe slightly toward the gravel. The pipe should be no more than 2 feet from the ground's surface.

8. Backfill the hole.

9. Replace the turf or sod.

Tips & Warnings

• Use a lightweight, corrugated plastic pipe. A light pipe won't sink in the dense soil and the plastic will not leach corrosive chemicals. In case of debris build up these pipes are easily replaced.

• Dense clay soils benefit from trench-style soakaways. The 6-foot depth remains but extend the length.

• Check soakaways and pipes annually. Redigging is necessary as silt can pile up.

• Check with your utility company and local ordinances prior to digging. Underground utility lines pose hazards.

References

• Home Extensions: The Complete Handbook; Paul Hymers; 2007; pg. 74