In Clark County, wet soil causes more trouble than rock, but basalt does show up. On HomeGuide's national scale, rock that must be broken lifts a dig from $2.50 to $15.00 a cubic yard up to $50 to $200 or more.
We did not set the dollar figures on this page: they are national ranges from HomeGuide. In Clark County, wet-season clay, trees, slope, groundwater and haul distance are what push a real job up or down. Figures checked October 2026.
What happens to the price if the excavator hits rock?
If the excavator hits basalt or large boulders, the dig slows and may need a breaker, so the price rises. HomeGuide prices hammered rock at $50 to $200 or more a cubic yard and notes rock on a foundation, basement or pool dig can add $15,000 to $20,000 or more. A written rock clause sets that rate up front.
How deep is bedrock around Vancouver?
Under much of Vancouver, thick layers of flood sand and gravel sit over the older rock, so bedrock is deep. In the hills around Camas, Washougal and the east county, basalt and weathered rock can come close to the surface. A test pit or soil report tells us before we price.
What if the ground is too wet, heavy clay or frozen to dig?
From November to April, clay soil in the north county is often too wet to compact, and machines rut and sink. We schedule grading for drier months, use crushed rock and fabric when work cannot wait, and pump water from deep holes. Frozen ground comes only with the occasional east wind cold snap.
Do I need a soil test before building?
For a new home, an ADU or a big addition, a geotechnical report is usually required in practice, especially on slopes or wet ground. It tells the engineer about bearing strength, groundwater and slope stability. For a geotechnical report, HomeGuide gives $1,000 to $5,000; simple soil tests are $10 to $100 or more.
How do you get equipment into a back yard through a narrow gate?
We use mini excavators and compact loaders that fit many side gates, and sometimes take down a fence panel and put it back. With no side access, the work is done by hand or with a machine lifted over, which costs more. Soft wet lawns may need mats for the whole route.
Will heavy equipment damage my lawn, and who fixes it?
Machines leave marks where they travel, and on a wet lawn they can leave deep ruts. We lay mats and stay on one path. Who repairs the lawn should be written in the contract, because finish grading and new sod or seed are often separate lines.
What if the dig finds an old foundation, slab, oil tank or contaminated soil?
Old footings, buried slabs and abandoned heating oil tanks turn up on older Vancouver and Portland lots. Debris comes out like any other. Stained or fuel-smelling soil is another matter: digging pauses until a test shows what it is. Lab tests for contamination run $25 to $200 a sample on HomeGuide's page.
Tell us about your project and we will come look at the ground, then send the scope and the price in writing. Call or text (360) 276-9112.