Drain Rock in Idaho
Also known as: 3/4 clean, washed rock
Backfill on an Idaho retaining wall or French drain needs Drain Rock when Palouse or Panhandle soil keeps moisture close to the work.
- Size: 3/4 inch to 1-1/2 inch
- Grading: Washed to remove fines and dust
- Type: Rounded or angular varieties
From $379.00 for 1 ton, delivery included
Larger loads cost less per ton: 500 tons is $21,095.00 ($42.19 per ton). Pick any quantity below for a delivered price.
Free delivery included
Free delivery anywhere in Idaho
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Weekday delivery, earliest Sep 25
“Five tons of drain rock went around the low side of the barn out near Buhl, where runoff used to pool ankle deep every time it snowed hard and thawed fast. Dug the trench myself over a weekend and let gravity do the rest. First real thaw since it went in, and the barn floor stayed dry for the first time since we built the place.”
Gus P. · Verified Buyer
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Everything You Need to Know About Drain Rock
Size and Grading
- Size
- 3/4 inch to 1-1/2 inch
- Grading
- Washed to remove fines and dust
- Type
- Rounded or angular varieties
Project conditions vary sharply from the freely draining alluvial gravel of the Treasure Valley to the water-holding ground of the Palouse and Panhandle. Drain Rock gives a drainage area clean, washed pieces without fines or dust, leaving connected gaps that carry water away through the aggregate. Rounded material fits visible drainage work because it has a natural stone appearance.
Behind a retaining wall, place angular Drain Rock in the backfill zone so it can interlock while supporting an open arrangement under the weight above it. The same clean aggregate is appropriate in French drains and septic leach fields where unrestricted flow is the purpose of the rock section. Matching the variety to the job helps Idaho property owners address ground that does not drain as readily.
Quickly Calculate How Much You Need
Material: Drain Rock
How to Measure
Measure the length and width of your project area in feet
Decide on depth in inches (2" for landscaping, 4" for driveways)
Enter the values above and we'll calculate the tonnage you need
Need help figuring out the right amount? We can help!
Call or text us at our contact form and we'll help you calculate the right quantity for your project.
Not sure how much you need? The River Rock Calculator has depth guides, coverage charts and worked examples for this material.
Common Uses
French Drain Systems
French drains use drain rock to create a path for water. The rock's open voids move water away from foundations, basements, and low areas, reducing the risk of water damage.
Septic System Drainage
For septic leach fields and drain fields, drain rock creates the drainage bed needed for wastewater infiltration. Clean material with uniform sizing supports systems built to health department specifications.
Retaining Wall Backfill
Backfill behind retaining walls needs drainage to release water before pressure builds. Drain rock keeps water moving through the backfill, helping avoid the pressure that can lead to wall failure.
Foundation Drainage
Set drain rock along foundations to carry groundwater away from footings and basement walls. This perimeter drainage reduces moisture infiltration and hydrostatic pressure that may cause cracks and structural damage.
Why Choose Drain Rock
Maximum Water Flow
Washed drain rock has dust and fine material removed, leaving voids for water to travel through freely. Those spaces support effective drainage as soon as the system is installed.
Long-Term Performance
Under load, the angular pieces of drain rock retain open spaces. Unlike rounded aggregate, they resist the settling and compaction that can restrict drainage flow.
Washed and Graded Rock
Drain rock is cleaned and sorted for drainage work requiring engineering specifications. It pairs with perforated pipe, drainage fabric, and the other parts of a drainage system.
Safeguarding Structures
Drain rock directs water away from retaining walls, foundations, and structures. Moving that water helps limit moisture damage and hydrostatic pressure that lead to expensive structural repairs.
Frequently Asked Questions About Drain Rock
Customer Reviews
Barn floor stopped flooding every winter
Five tons of drain rock went around the low side of the barn out near Buhl, where runoff used to pool ankle deep every time it snowed hard and thawed fast. Dug the trench myself over a weekend and let gravity do the rest. First real thaw since it went in, and the barn floor stayed dry for the first time since we built the place.
Gus P. · Buhl, ID · Verified Buyer
Dry well finally does its job
Two tons went toward a dry well at the bottom of the downspout run here in Orofino. Clean, no fines, drained the first big storm we tested it with. Simple fix for a problem that bugged us for years.
Nadia S. · Orofino, ID · Verified Buyer
Big Chunks But Wall Stopped Moving
Our retaining wall behind the shop in Wallace kept leaning a little more every wet season until we finally backfilled it right. We had six tons of drain rock delivered, and the driver worked the tandem carefully down our narrow gravel drive without clipping the fence posts. Most of the load was clean and well graded, but a handful of chunks were bigger than expected, big enough that we had to break a few apart with a hammer before they would fit behind the wall face. Once packed in, the wall stopped moving even through the heavy spring runoff we get off the hillside.
Colby W. · Wallace, ID · Verified Buyer
Foundation finally stays dry through spring melt
Three tons of drain rock for a French drain around the north side of the house in St. Maries, where snowmelt used to pool against the foundation every March. Idaho Rock Supply's driver dumped it close enough to the trench that we barely had to wheelbarrow any of it. Wrapped it in fabric like the yard recommended, and the crawlspace has stayed bone dry through two wet springs now.
Blake H. · St. Maries, ID · Verified Buyer
Drain Rock has 4 verified customer reviews with an average rating of 4.8 out of 5.
