Cojo runs excavation crews into the 97116 zip -- Forest Grove, the Washington County town at the western edge of the Tualatin Valley on Highway 47. The local work splits between hillside subdivision cut and fill on the gentle ridges west and north of town, foundation digs for the Pacific University adjacency and downtown infill, and drainage retrofit work on older homes along Gales Creek and its tributaries. Pricing depends on volume of material, soil type, and disposal distance, but most local jobs land within the published baseline range below.
Excavation Work in Forest Grove -- The Local Picture
Forest Grove's geography drives most of what we excavate. The town sits at the western edge of the Tualatin Valley with the Coast Range rising immediately to the west. That topography produces three distinct excavation contexts:
Town center and downtown infill. Flat to gently sloped lots, mostly residential and small commercial. Foundation digs, basement waterproofing trenches, utility connections.
Western hillside subdivisions. Gentle ridges with new and ongoing subdivision build-out. Significant cut-and-fill work to create level building pads, retaining-wall excavation, and engineered slope work.
Gales Creek corridor. Older homes along the creek and its tributaries that often need drainage retrofit -- French drains, perimeter drains, sump-pump pits -- because the original 1950s-1970s construction didn't account for the current drainage standards.
Pacific University on the southeast edge of town shapes a steady demand for student-housing additions, ADUs, and small commercial infill projects in the surrounding neighborhood.
Washington County stormwater code applies to any work that creates or modifies impervious surface or affects creek-setback areas. The Gales Creek setback specifically has riparian rules that limit excavation distance from the high-water mark. We handle the setback verification and permitting on creek-adjacent projects.
Common Excavation Scopes in 97116
The four jobs we see most:
- Hillside cut and fill -- moving substantial volumes of soil to create a level building pad on a sloped lot. Engineered slope work is typical for subdivisions.
- Foundation excavation -- digging the footprint for a new home, ADU, or addition. 2 to 6 feet deep on most local work.
- Drainage retrofit -- French drains, perimeter drains, sump pits. Common on older Forest Grove homes near the creek.
- Utility trenching -- water, sewer, electric, gas. Coordinated with city of Forest Grove public works for any right-of-way work.
We also handle stump and root removal, brush clearing, and small demolition. Forest Grove jobs that mix multiple scopes -- driveway plus drainage plus utility trench -- usually run 15 to 25 percent cheaper combined than separate mobilizations.
Excavation Cost in 97116
Industry Baseline Range
| Scope | Typical Range |
|---|---|
| Driveway excavation (residential) | $2,500 to $15,000+ |
| Foundation excavation (small home/ADU) | $3,500 to $18,000+ |
| Hillside cut and fill (per cubic yard) | $20 to $80+ |
| Drainage trenching (per linear foot) | $25 to $75+ |
| Utility trenching (per linear foot) | $20 to $60+ |
| Stump removal (per stump) | $150 to $500+ |
| Soil disposal (per cubic yard) | $8 to $25+ |
Current Market Reality
The published ranges assume reasonable soil conditions, no buried surprises, and a single mobilization within 30 miles of our equipment yard. Forest Grove jobs that find tree roots, old septic lines, or unstable hillside fill blow past the baseline. Hillside work specifically has variability -- a stable subgrade can be excavated efficiently; an unstable one needs over-excavation and geotextile, sometimes engineered slope reinforcement. Disposal fees have climbed; clean dirt now runs $8 to $20 per cubic yard at the nearest accepting site, contaminated soil significantly more. Fuel and labor surcharges still ride on equipment hours. Quotes older than 30 days should be re-validated.
Washington County Subgrade and the Creek Setback
The 97116 footprint sits on a mix of soils. The valley-floor portion of town is mostly Aloha silt loam over a clay subsoil -- the standard Tualatin Valley profile. The western hillsides are mixed Cornelius silt loam over weathered basalt, with localized colluvium where the slope has moved historically. That has two practical effects:
Drainage retrofit volume. The clay subsoil holds water hard. Older Forest Grove homes with marginal original drainage almost always need retrofit work by year 30 to 40. Standing water in crawl spaces, basement seepage, and yard ponding all point at the same problem.
Hillside stability. Colluvial soil on the western ridges is movement-prone. Cut-and-fill work on these lots needs proper engineering, not just dirt-moving. We coordinate with geotech and structural engineers on any cut that exceeds 4 feet vertical face.
Creek setback. Gales Creek and its tributaries have an Oregon DEQ riparian protection setback. The exact distance varies by classification but ranges from 25 to 75 feet from the high-water mark. Excavation in the setback requires permits and often engineered erosion control.
For broader Oregon cost context, see our driveway excavation cost guide. For clay soil specifics, see clay soil excavation in Oregon. For the residential driveway scope, see our driveway excavation Forest Grove article.
Picking an Excavation Contractor in 97116
What to verify:
- Oregon CCB license -- required, easy to verify on the state CCB website.
- Equipment match -- the quote should specify the machine; a 90,000-pound excavator doesn't belong on a tight downtown lot, and a Bobcat won't move a subdivision pad.
- Disposal plan -- where the soil goes matters. Quotes that don't list disposal are often hiding the fee.
- Erosion-control plan -- required during October-April wet season. Should be on the quote.
- Locate ticket on file -- 811 utility locates are legally required before digging.
- Geotech coordination -- for hillside or creek-adjacent work, the quote should reference geotech involvement.
- Insurance -- general liability and workers' comp.
For backyard regrading and drainage scope specifically, see backyard grading cost in Oregon.
Get a Site-Specific Quote for 97116
Cojo runs excavation crews across Washington County and the Tualatin Valley from our Hood River HQ and regional field operations. We hold an Oregon CCB license, carry general liability and workers' comp insurance, and quote against the actual site, not a hourly rate from a phone call. If you need a hillside subdivision pad, a Pacific University-adjacent ADU foundation, or a drainage retrofit on an older Forest Grove home, request a quote and we'll schedule the walkthrough.