Pea Gravel vs River Rock

Both pea gravel and river rock are smooth, rounded stones — but they differ in size, cost, drainage, and best applications. Here is a direct comparison to help you pick the right one.

Quick comparison

Factor	Pea Gravel	River Rock
Size	3/8 inch (pea-sized)	1–5 inches
Shape	Round, smooth	Round, polished
Cost (bulk)	$30–$55 / cu yd	$45–$130 / cu yd
Drainage	Good	Excellent
Stability	Low (shifts)	Moderate
Best for	Paths, playgrounds, mulch replacement	Drainage, dry creeks, pool surrounds

Pea gravel — best uses

Playground ground cover — soft, cushioning, safe for falls
Garden paths — good drainage, comfortable on bare feet
Dog runs — does not compact or get muddy
Vegetable garden mulch replacement — keeps weeds down without decomposing
Patio base filler — fills gaps between stepping stones

River rock — best uses

Dry creek beds — large stones mimic a natural stream look
French drain topping — improves drainage channel appearance
Pool surrounds — smooth surface, comfortable underfoot
Erosion control on slopes — heavy enough to stay put in rain
Foundation drainage — directs water away from house footings

How much do you need?

Both materials are measured in cubic yards. Use this formula:

Volume (cu yd) = Length (ft) × Width (ft) × Depth (in) ÷ 324

Typical depths: 2–3 inches for decorative coverage, 4–6 inches for drainage.

Use the Gravel Calculator to get exact quantities and ton estimates.

Coverage per ton

Material	Coverage at 2” deep	Coverage at 3” deep
Pea gravel	~100 sq ft / ton	~65 sq ft / ton
River rock (small, 1”)	~80 sq ft / ton	~55 sq ft / ton
River rock (large, 3–5”)	~60 sq ft / ton	~40 sq ft / ton

Coverage varies by exact size and bulk density.

Can you mix them?

Yes — pea gravel and river rock are sometimes layered. River rock on top for aesthetics, pea gravel below for drainage. For French drains, larger river rock around the pipe and smaller pea gravel backfill on top is a common combination.

Frequently Asked Questions

What is the difference between pea gravel and river rock?

Pea gravel is small (3/8 inch), uniform, rounded stones typically used for paths, playgrounds, and garden beds. River rock is larger (1–5 inches), polished, and used for drainage, dry creek beds, and decorative borders.

Which is cheaper — pea gravel or river rock?

Pea gravel is generally cheaper at $30–$55 per cubic yard bulk. River rock costs $45–$130 per cubic yard depending on size and finish. Both are sold by the ton at landscape supply yards.

Is pea gravel good for drainage?

Pea gravel drains well, but river rock (larger stones) drains faster. For French drains and deep drainage trenches, river rock or crushed stone is preferred. Pea gravel works well for surface drainage on paths and patios.

Does pea gravel shift underfoot?

Yes — pea gravel is loose and moves underfoot, which some find uncomfortable. River rock is more stable for walkways because the larger stones interlock better. For high-traffic paths, consider compacted crushed gravel instead.

Can I use river rock around a pool?

Yes. River rock is a popular pool surround because the smooth, round stones are comfortable underfoot and do not scratch bare feet. Use a weed barrier underneath to keep it clean.