In retaining wall applications where water is a large concern, a heel drain is often incorporated. The purpose of the heel drain is to pick up any water that migrates from behind the retaining wall structure at the cut, then route the water away from the reinforced mass.
Similar to the toe drain, the pipe may be a rigid pipe with holes at the bottom or a corrugated perforated flexible pipe.
The heel drain should be vented at 100 ft (30 m) intervals along the entire length of the wall and should not be tied into the toe drain system.
For infill soils with a high percentage of sand and/or gravel the heel drain pipe does not need to be surrounded by wall rock. (ref. BP, Chapter 4.2)
Allan Block is working to achieve our industry initiative of Zero Wall Failures. With our Best Practices Manual and experience in the industry we are trying to expand the knowledge base for the design of segmental retaining walls (SRW's) by communicating and educating the professionals in the industry. To see the full Best Practices Manual, visit allanblock.com to download today and keep an eye out for more industry Best Practice recommendations here.