Drain Rock vs River Rock
Both look similar, but they solve different problems. Drain rock is a functional drainage aggregate. River rock is a decorative topping. On most jobs you use both — drain rock inside the drain, river rock as the visible layer.
Drain Rock
- Washed and screened
- Angular or rough — locks in place
- Sold for flow rate, not looks
River Rock
- Smooth, water-tumbled
- Sold for appearance
- Not ideal for high-flow drainage
| Spec | Drain Rock | River Rock |
|---|---|---|
| Primary use | Drainage | Decoration |
| Shape | Angular / rough | Smooth / rounded |
| Washed? | Yes | Usually |
| Common sizes | 3/4", 1", 1 1/2" | 3/8"–2", 2"–4", 4"–8" |
| Density | 1.35 t/yd | 1.35 t/yd |
Verdict
For French drains, dry wells, and behind retaining walls: drain rock. For dry creek beds, landscape topping, and decorative drainage swales: river rock. Use both together for the best look and function.