Order 5/8 Minus and Crushed Stone in King County, WA
Washington Rock Supply delivers gravel, stone and aggregate in King County, WA. Winter rain soaks the loose upper soil, hits the dense till below and stops, so water sits near the surface instead of draining away.
5/8 minus is the Washington answer to that. It is crushed rock with the fines left in, so it packs hard and sheds water instead of soaking it up.
Order it for drives, parking pads and shed slabs.
Delivery across King County
Order online and pick your quantity by the ton or by the yard. Each product page has a calculator to help you size the load.
Delivery covers Seattle, Bellevue, Kent, Renton, Federal Way, Kirkland, Auburn, Redmond, Sammamish, Issaquah, Maple Valley, Mercer Island, Kenmore and Snoqualmie.
Have the drop spot clear before the truck arrives. The driver tips the load and leaves; the material stays where it lands, so pick a spot you can work from.
Materials delivered in King County
King County spans two ground regions, and both shape what you order. The Puget Sound lowland runs on dense glacial till with perched water sitting on top of it.
5/8 minus is the Washington default surfacing course.
Contractors shorten those to CSBC and CSTC and order them as 1 1/4 minus and 5/8 minus.
1 1/4 minus goes below a 5/8 minus top course. It has a larger top size and fewer fines, so it carries load and stays workable on soft wet ground.
Where water is the problem, switch to washed stone. Drain Rock keeps its voids in a footing drain or curtain drain.
3/8" Crushed Stone works in paver joints and small drain runs.
For surfaces, Walkway Gravel packs tight on garden paths. Stone Screenings bed pavers and flagstone.
Driveway Gravel suits long rural approaches.
Rounded stone is a separate family. Natural Pea Gravel suits play areas and planting beds.
Washington River Rock lines dry creek beds and splash pads. Large River Rock armours swales and culvert outfalls.
Sand and soil round out the list. Washed Sand goes into concrete mixes and pipe bedding.
Mason Sand goes into mortar and stucco. Top Soil and Garden Soil cover lawn repair and raised beds.
Ground conditions across King County
In the Puget Sound lowland around Seattle, Bellevue, Kent and Renton, the ground is glacial material left by the Vashon ice sheet. A dense till cap sits over advance outwash sand, with silt and clay below that.
Perched water is the driver there. Rain soaks the loose upper soil, reaches the dense till and stops, so the water table sits close to the surface all winter.
Bluff failure follows from the same water. Winter rain perches where outwash sand meets the clay below it, and that perched water undercuts cut slopes and fill on a smaller scale.
In the Cascade Range and the east-slope valleys around Snoqualmie and North Bend, the soil is thin and stony over volcanic and granitic rock, with andesite, pumice and ash around the volcanoes. The west slope takes 75 to 90 inches of rain a year near the crest and sheds it fast off steep ground.
Steep-slope runoff scours road shoulders, ditches and culvert outfalls there. Debris flows and washouts follow heavy rain on snow, and bare burned ground sheds sediment for years after a fire.
The working season splits the same way. In the lowland the wet season runs October through April, and exposed soil must be stabilized within two days in that window against seven days in summer.
Base, paving and paver work is scheduled for the dry months.
In the mountain valleys the window is short. Snow closes the high ground, so work runs roughly from late spring to early autumn, later at elevation.
Frost is a lowland footnote and a real problem uphill. King County publishes an 18 inch frost depth, set by the local building department.
Choosing the right material
Kittitas County sits in the Cascade Range and the east-slope valleys, the same ground region as the King County foothills. Its slopes carry thin, stony soil over volcanic and granitic rock, with andesite, pumice and ash around the volcanoes and glacial and river gravel on the valley floors.
Pierce County and Snohomish County share King County's ground regions. Both span the Puget Sound lowland and the Cascade Range and east-slope valleys, so the till, the perched water and the steep-slope runoff behave the same way.
The material choices carry across unchanged.
Order 5/8 Minus and Crushed Stone for Your King County Job
5/8 minus is the Washington surfacing course for drives, pads and slabs, and it pairs with 1 1/4 minus underneath. Add drain rock where perched water sits on the till.