Pea Gravel in Wisconsin: 3/8 Inch Rounded Stone for Places People Walk

The decision most people are actually making is softer than it sounds: what goes on the ground between the cabin and the dock, or under the swing set, or along the path to the shed. Something that drains fast after a summer storm, does not need renewing every spring the way bark does, and is comfortable to stand on. Pea gravel is usually the answer to that question, and it is usually the wrong answer to the different question of what to do about water under the ground.

The material is small, smooth and naturally rounded, about 3/8 inch, in tans, creams, grays and browns with the odd red. The rounding is what makes it pleasant underfoot and what makes it roll.

Rounded 3/8 inch stone underfoot, and what it looks like at the lake

• Pieces are water-worn rather than crushed, so there are no sharp edges to sit on, kneel on or go barefoot over.
• The color mix is varied rather than uniform, which suits the informal edges most properties up here have and hides dust between rains.
• It moves under a foot. A layer of it is comfortable to stand on and slightly loose to walk on, which is fine for a path and awkward for a wheelbarrow.
• Water goes straight through it. After a thunderstorm the surface is walkable while the lawn is still squelching.
• It does not fade, rot or need replacing on a cycle. What it does over the years is collect leaf litter and grit, which is the whole of its maintenance story.

Paths, play areas and dog runs that dry out fast after a storm

• Garden paths and the route between a cabin and a dock, where a soft, fast-draining surface beats turf that gets worn to mud.
• Play areas under swings and climbers, where rounded stone is kinder than anything crushed.
• Patio spaces and seating areas with a loose, informal finish.
• Dog runs, where the surface has to drain and be rinsed off rather than grow anything.
• Shore strips and the ground around a pond, giving a walkable margin between water and lawn.
• Ground cover in beds and around foundation plantings, where the point is a neat, stable surface rather than growing conditions.

Why pea gravel is the wrong answer to a wet basement or a farm lane

• It does not fix water below the surface. A soft spot, a wet basement wall or a spring seep needs a trench with an outlet, built with Drain Rock, and the pea gravel goes on top afterwards if you want it to.
• It is not a driveway. Rounded 3/8 inch stone rolls out from under a tire, rides to the edges and never firms up. A lane wants a compacted 3/4" Traffic Bond base with a driveway surface over it.
• It is not a paver bed. Pavers set on rounded stone move, because rounded pieces have nothing to lock against.
• On a slope steeper than very gentle it creeps downhill with every rain and every set of boots.
• Where a plow runs, it gets thrown into the lawn. Keep it away from the edge of anything that gets cleared in January.

How deep to lay it, and what goes underneath

• Two inches over a prepared base for a decorative ground cover, three inches for anything that gets walked on regularly.
• A play area wants more depth than a path, and the depth is there to cushion rather than to cover, so measure that one on its own terms.
• The base matters more than the stone. Strip the sod, cut down so the finished gravel sits level with the surrounding grade, and lay woven fabric before anything goes in.
• Give it a rigid edge. Steel or aluminum edging, a timber, or a mortared stone border all hold through a Wisconsin winter. Thin plastic roll edging lifts with the frost and the line goes with it.
• Deeper is not better. An overfull path is a path you sink into, and the surplus ends up in the grass.

Yardage for two splash pockets, a low wall drain and a shore strip

Length times width times depth in inches divided by 12, then divided by 27, gives cubic yards. This site's calculator lists pea gravel at about 2,800 lb per cubic yard, which is 1.40 tons per yard.

• Example, two splash pockets under downspouts, each 5 ft by 4 ft at 3 inches, so 40 square feet together: 40 x 0.25 = 10 cubic feet, divided by 27 = 0.37 cubic yards, times 1.40 = about 0.5 tons.
• Example, a chip drain behind a 24 ft low garden wall, 8 inches wide and 3 ft high: 24 x 0.67 x 3 = 48 cubic feet, divided by 27 = 1.8 cubic yards, times 1.40 = about 2.5 tons. For a taller structural wall, angular 3/4" Crushed Stone is the better backfill, because it holds its arrangement under load.
• Example, a shore strip 25 ft long and 6 ft wide at 3 inches: 150 square feet x 0.25 = 37.5 cubic feet, divided by 27 = 1.4 cubic yards, times 1.40 = about 1.9 tons.

A cubic yard covers about 162 square feet at 2 inches and 108 square feet at 3 inches. Those are approximations and the weight is a published average. The pea gravel calculator will take the measurements and hand back a tonnage, with a small extra allowance added by default so a path does not run out three feet short.

Screenings, 3/8 inch chips and River Rock alongside pea gravel

Work out the yardage, then set a quantity and a date on this page. Delivery is arranged at checkout by ZIP code, so choose a dump spot with clear access, ideally on a tarp and as close to the work as a truck can sensibly get.