Water is enemy #1 for all retaining walls, and must be managed with post construction management details as you will see in our water management section on allanblock.com. When water is present in soil behind a retaining wall, it will add significant weight and pressure to the wall which may cause concern. For that reason, routing water away from the wall after—construction and even during construction—is a Best Practice for Segmental Retaining Wall Design and should be done whenever possible.
As read in Chapter 6 of the Allan Block’s Best Practices for SRW Design manual, backfill should be graded to avoid water accumulation behind the wall, or in the reinforced zone at the conclusion of each day’s construction. This may require a temporary berm at the back of the reinforced zone as outlined in 6-11 on the detail below, indicated by the red arrow. This is done to help reduce the amount of water that may accumulate behind the wall, which adds weight and pressure that the wall was not designed for. For more tips on construction, including water management details, visit our Retaining Walls by Allan Block guide or our Design for Water section that outlines post construction recommendations and the potential need to temporarily control water during construction.