Excavation & Site Prep in Adair Village, Oregon: 2026 Guide

Excavation & Site Prep in Adair Village, Oregon

Excavation is the foundation work that decides whether everything built on top of it holds up. In Adair Village, a growing Benton County community north of Corvallis, that means dealing with Willamette Valley soils that can range from well-draining to clay-heavy ground that holds water. Grading and drainage are the heart of almost every site-prep job here.

Cojo Excavation & Asphalt handles excavation, grading, drainage, utility trenching, and land clearing across Benton County from our Willamette Valley base. This guide covers what excavation costs, how local soils and permits factor in, and what a job looks like start to finish.

What Excavation Costs in Adair Village

Excavation pricing is driven by volume of material, soil type, access, haul distance, and what you are digging for. A clean, dry, accessible site moves fast; a wet site with soft soil and tight access costs more.

Industry baseline ranges shown below. Actual costs vary widely with soil conditions, water table, access, haul distance, disposal fees, and project scope.

Service	Industry Baseline Range
Site grading	$1.50–$5.00 per sq ft
Excavation (general)	$50–$200 per cubic yard
Utility trenching	$10–$25 per linear foot
Land clearing	$1,500–$5,000+ per acre
Drainage installation	varies by system

These are reference ranges only. Excavation carries more cost variables than almost any other trade, so a site visit is the only way to get a real number. Our Oregon excavation cost guide explains what moves these figures.

Willamette Valley Soils and Drainage

Adair Village sits on valley soils that often include clay, which holds water and complicates excavation. Wet clay is heavy and slow to move, soft spots may need to be dug out and replaced with engineered fill, and the swell-shrink behavior of clay makes drainage critical.

We grade sites to move water away from structures and pavement, install French drains and catch basins where needed, and set finished grades that shed water rather than pool it. On clay-heavy valley lots, drainage is not optional. It is the difference between a site that stays stable and one that fails.

Erosion Control and Permits

Oregon and Benton County regulate ground disturbance to protect water quality. Once a project disturbs ground above a certain size threshold, erosion and sediment control measures are required, and larger projects may need a stormwater permit. Work near a waterway or wetland carries additional rules.

We know which thresholds apply and build the required erosion controls, silt fences and sediment barriers, into the job. For grading-heavy sites, our site grading cost in Oregon guide explains the process in more depth.

Call Before You Dig: The 811 Locate

Every excavation job in Oregon legally starts with a call to 811. Utility locators mark buried gas, electric, water, sewer, and communication lines before any digging. This is free, required by law, and prevents strikes that cause injury, outages, and liability.

We handle the 811 locate as standard practice on every job. Any contractor who skips it is one to avoid.

What We Excavate For

Most Adair Village excavation work falls into a few categories:

• Driveway and pavement prep — Excavating and grading the sub-grade for a stable, well-drained base, tied directly to our asphalt paving in Adair Village work.
• Drainage — French drains, catch basins, and regrading to solve standing-water problems.
• Utility trenching — Trenches for water, sewer, and electrical lines, dug to depth and backfilled properly.
• Land clearing — Removing brush, stumps, and debris to open a site for building or paving.
• Site grading — Shaping a lot for proper drainage and a level building or paving surface.

How a Job Runs

We start with a site walk to understand soil, drainage, access, and scope. We confirm permit and erosion-control requirements, place the 811 locate, and mobilize equipment sized to the job. As we work, we manage water, control erosion, and compact fill in lifts so the finished site is stable. Final grading sets the site up to drain and carry whatever comes next.

Getting an Excavation Quote

Because excavation cost depends so heavily on what is underground and how the site drains, an accurate quote needs a site visit. We assess conditions, confirm permits, and give a clear scope and price. We serve Adair Village and nearby Corvallis and the rest of Benton County.