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Bags of River Rock for a 6x50 Walkway

How many bags of river rock for a 6x50 walkway: at 3 inches deep you need about 75.0 cubic feet, which is 150 bags of the common 0.5 cubic foot size. If your store sells river rock in 50-pound bags instead, figure about 150 bags, since river rock weighs roughly 100 pounds per cubic foot.

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Bag count by depth

DepthCubic feet0.5 cu ft bags50 lb bags (approx.)
1 in25.05050
2 in50.0100100
3 in75.0150150
4 in100.0200200

How to figure it

  1. Area: 6 × 50 = 300 sq ft.
  2. Volume: 300 × (3 ÷ 12) = 75.0 cu ft.
  3. Bags: 75.0 ÷ 0.5 = 150 bags (round up).

Bags or bulk?

A cubic yard is 27 cubic feet, so 75.0 cubic feet is 2.78 yards, about 3.8 tons. At this size, a bulk delivery usually beats a cart full of bags once you count trips. Compare the bag price × 150 against a bulk quote for 4.1 tons delivered.

About river rock

River rock is smooth, water-worn stone sold in sizes from about 3/4 inch to several inches. Larger sizes cover fewer square feet per ton at the same depth because the voids between stones are bigger.

Before you spread for a walkway

  • Dig and level. Remove sod and set the base slightly below the surrounding grade.
  • Edge it. Steel, plastic or stone edging keeps material in place.
  • Spread in layers. Rake to depth, then rake smooth; rounded stone will not compact.
  • Buy a few extra. Grab 5 to 10 percent more bags for settling and touch-ups.

The volume and tonnage calculator handles other sizes and depths.

When to choose river rock

Works well for:

  • Dry creek beds and drainage swales
  • Decorative borders and planting beds
  • Around downspouts to stop splash erosion

Poor fit for:

  • Walking surfaces
  • Driveways
  • Bases under slabs or pavers

Quick reference numbers

  • Per inch over 100 sq ft: about 0.42 tons of river rock (0.31 cubic yards).
  • Per inch over 1,000 sq ft: about 4.2 tons.
  • Another size for comparison: a 15x30 area at 4 inches takes about 7.5 tons.
  • Weight used here: about 1.35 tons per cubic yard.

Common estimating mistakes

  • Ordering exactly the math. Uneven ground and spillage nearly always need a little more than the flat calculation.
  • Mixing up cubic yards and tons. Yards are volume, tons are weight; convert with the product’s weight per yard.
  • Skipping drainage. Water sitting under any surface softens the base and leads to ruts and potholes.
  • Ignoring the base. A thin surface layer over soft soil fails early no matter how much material is on top.

Questions people ask

How many bags of river rock for a 6x50 walkway?

About 150 bags of 0.5 cubic feet at 3 inches deep.

How many 50 lb bags of river rock for 6x50?

About 150 bags at 3 inches.

How many 0.5 cubic foot bags are in a cubic yard?

54 bags.

How many cubic feet is a 6x50 walkway at 3 inches?

About 75.0 cubic feet.

When does bulk make more sense?

Usually once the job passes about a cubic yard, or when you would need more than a few car trips.

Related guides

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