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River Rock Calculator

Quick answer: River rock quantity is area × depth, where depth should be about 1.5 to 2 times the stone size so soil does not show. A 25 × 4 ft border with 3 inches of 1 to 2 inch rock is about 0.93 yd³, or roughly 1.3 tons at 1.35 tons per yard. Larger stone needs more depth.

How the estimate works

Larger rounded stones leave bigger gaps, so coverage depends on size. Dry creek beds usually vary in depth, so measure an average. For mixed sizes, the bigger stones set the minimum depth.

Worked example: river rock calculator

Illustrative examples (2026-10-29), not quotes or guarantees.

25 × 4 = 100 ft² × 0.25 = 25 ft³; +5% = 26.25 ft³ ≈ 0.97 yd³ ≈ 1.31 tons.

FAQ

How deep for 2–4 in rock?

Often 4–6 in so the soil is covered.

Fabric under river rock?

See landscape fabric.

River rock vs pea gravel?

See gravel types.

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