Those little openings near the bottom of a well-built retaining wall aren't decoration and they aren't sloppiness. They're the reason the wall is still vertical.
The physics, in plain English
A retaining wall is sized to hold back soil. But clay soaks up rain like a sponge, and saturated soil pushes with dramatically more force than dry soil — the water itself adds hydrostatic pressure across the whole back face of the wall. A wall built for dry dirt, holding wet clay, is a wall carrying a load nobody designed it for. Clay never gets tired. Walls do.
The drainage system, back to front
Gravel backfill. Directly behind the wall goes free-draining gravel instead of native clay. Water passes through it instead of building pressure against the concrete.
Drain pipe. At the base of that gravel, a perforated pipe collects the water and carries it out to daylight — somewhere planned, not "wherever."
Weep holes. Openings through the wall face near the bottom, the pressure-relief valves of the system. Water that reaches the wall gets out through it instead of pushing on it.
Compacted backfill in lifts. The soil above the drainage zone goes back in thin, compacted layers — loose-dumped backfill settles, holds water in pockets, and drags on the wall.
Why this gets skipped
Every part of the system is invisible when the job is done. Two walls can look identical the day they're finished; only one of them has somewhere for the water to go. Guess which bid was cheaper.
It's the same story as every slab we pour: the work that matters most is the work that gets buried. So we photograph the footing, the gravel, the pipe, and the weep holes before the backfill goes in — and text it to your phone. Proof, not promises.
