Crushed Base Course, Sand and Gravel Delivery in Missoula County, MT
Montana Rock Supply delivers gravel, stone and aggregate in Missoula County, MT. The base material here is crushed base course, the 3/4 minus rock that carries driveways, shop pads and parking areas.
Valley floors hold Glacial Lake Missoula silt and clay, with sand and gravel outwash along the rivers. That ground decides how a base is built and how it drains.
Materials Delivered in Missoula County
Start with the job. A driveway, a patio and a drain each call for a different material, and the local name is the one to use when you order.
Crushed base course is specified in Montana as crushed base course. The MDT Standard Specifications cover it under Section 701.02.4, where grades are named by nominal top size: Grade 5A at 2 inch minus and Grade 6A at 1 1/2 inch minus.
A 3/4 inch minus grade, 7A, was developed for MDT as pit sources for the larger sizes ran short. City and county work is more often written against Section 02235, Crushed Base Course, of the Montana Public Works Standard Specifications.
County road standards call sizes out the same way, as 3 inch minus sub-base and 1 inch minus crushed base or top course.
Drainage and decorative stone
Use 3/4" Crushed Stone for drainage beds, pipe bedding and construction entrances. 3/8" Crushed Stone suits fine drainage and trench bedding.
3/8" Natural Pea Gravel works on walkways, play areas and dog runs. Large River Rock handles dry creek beds and splash pads under downspouts.
For sand, Mason Sand goes into brick and block work, paver joints and play sand. Washed Sand levels and beds flatwork and pavers.
Ground Conditions Across Missoula County
Missoula County spans two ground regions, and the soil under a project changes the material call.
In the western intermontane valleys around Missoula, Lolo, Frenchtown and Clinton, Glacial Lake Missoula silt and clay covers the valley floors. Coarse sand and gravel outwash and alluvial fans run along the rivers, and the benches and mountain fronts carry shallow stony ground.
Lake-bed silt drains slowly and stays soft well into spring. River gravels beside it drain fast.
Snowmelt off the surrounding ranges puts the Clark Fork, Bitterroot and Blackfoot up through May and June.
Bank scour at high water, gully cutting in silt benches and heavy runoff off burned ground all move soil. Riprap and washed rock armor those spots.
Toward Seeley Lake and Condon, the ground is glacial till and outwash with deep lake silt and clay on the valley floors and gravel benches above them. Thin stony soils sit over rock on the forested slopes.
That is the wettest corner of the state. Rain and snowmelt come off steep forested ground, and runoff off logged and burned slopes scours stream banks at spring high water.
Frost depth is about 36 inches as the figure commonly used in Missoula, with deeper figures at higher elevation. The local building department sets footing depth.
Silty valley ground has to dry out before it will compact. Saturated spring ground and frozen winter ground both stop proper compaction, so base, driveway and paver work runs from breakup into late fall.
Delivery Across Missoula County
Order online and pick your delivery. Choose a quantity by the ton or by the yard, and each product page has a calculator to help size the load.
Pick a delivery date at checkout, and a dump truck tips the load on site in one pile. Coverage reaches Missoula, Lolo, Seeley Lake, Frenchtown, Clinton, Condon, Huson and Bonner.
Larger loads suit bulk fill and base work, where pit run, fill dirt or crushed base course goes down in volume. Smaller loads suit bedding sand, crusher fines and decorative stone.
Choosing the Right Material
Granite County sits in Southwest Montana, over gravelly alluvium and outwash on high basin floors, with clay-rich basin fill in places. Its ground differs from the lake silt and clay of the Missoula valley floors, so a base there starts from different material.
Lake County and Sanders County share the ground region that covers Seeley Lake and Condon: glacial till and outwash, deep lake silt and clay on the valley floors, gravel benches above them, and thin stony soils over rock on the forested slopes.
Where that ground is the same, the base and drainage choice is the same. Crushed base course for a compacted base, washed rock where water has to move.
On slow-draining silt, a drainage layer and clean stone matter more than on fast river gravel. On stony benches, a screened topsoil or garden soil carries a lawn that native ground will not.
Order Crushed Base Course in Missoula County
Crushed base course is the material most Montana ground is built on, and it is the place to start a driveway, a pad or a parking area.
Montana Rock Supply delivers gravel, stone, sand, topsoil and aggregates across Missoula County. Order online by the ton, choose your delivery date, and a truck brings the load to your site.