What is a fundamental requirement for retaining walls to function properly?

For retaining walls to function properly, the incorporation of weep holes and batter is essential. Weep holes are small openings that allow groundwater to escape from behind the wall. This drainage is crucial for relieving hydrostatic pressure, which can otherwise cause the wall to fail due to the buildup of water. Without these drainage methods, water can accumulate and exert significant pressure, potentially leading to structural issues or even collapse.

Batter refers to the practice of setting the wall back at a slight angle toward the earth it retains. This design helps improve stability by ensuring that the weight of the soil acts more directly on the wall, enhancing its ability to resist lateral forces. Both weep holes and batter work together to ensure effective management of water and structural integrity, making them fundamental requirements for retaining walls.