Calculate volume and weight of river rock needed for landscaping, drainage, and decorative applications.
Last updated: March 2026
River rock (also called river stone) consists of smooth, rounded stones formed by water erosion over millions of years. Unlike angular gravel, river rocks have naturally polished surfaces and varied shapes, making them ideal for both functional and aesthetic landscaping.
Common uses: Drainage systems, decorative mulch alternatives, pathways, stream beds, water features, and landscape design. River rock improves drainage, prevents soil compaction, and requires minimal maintenance.
Density: River rock typically weighs approximately 1.325 metric tons per cubic yard (or ~2,650 lbs per cubic yard), accounting for packing and moisture.
River rock for a 20 ft × 12 ft pathway (3 inches deep):
River rock is used for decorative landscaping, drainage layers under gravel, stream beds, water features, pathways, and soil stabilization. It's popular because of its aesthetic appeal and minimal maintenance.
Typically 2-4 inches (5-10 cm) for decorative purposes. For drainage applications, use 3-6 inches. Add landscape fabric underneath to prevent weed growth and stone sinking.
River rock requires more processing due to its smooth, rounded nature and larger individual stones. It's harvested from riverbeds and is less available than crushed gravel.
Use landscape fabric or edging around the perimeter. Larger river rocks (2-4 inches) are less prone to spreading than smaller stones.
Yes! River rock is ideal for wet areas, stream beds, and drainage systems. It improves water flow and won't compact or deteriorate from moisture.
River rock lasts 10+ years if installed properly with landscape fabric. Replace only when spreading occurs or rocks migrate. Top-dress annually to maintain appearance.
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