Licensed contractor in Boulder County, Colorado

We do more than dig a hole and drop in a tank.

Tri-Lakes Contracting is a licensed septic installer, excavation contractor, and custom home builder working throughout Boulder County. Site work and septic permitting are the critical first steps before you can even break ground on a build — and they’re exactly what we handle, start to finish.

Because we hold the septic, driveway, and building sides in-house, we bundle them into one path instead of stitching together three separate contractors: soil testing and engineered design, excavation and grading, the septic system, water storage, and the home itself — one crew, one point of contact, on your schedule.

We know Boulder County terrain inside and out — steep foothill and canyon lots, decomposed granite, and wildfire-interface ground. Whether your property is in Boulder, Longmont, Nederland and Lyons, we deliver site work built for Front Range foothills conditions and permitted under Boulder County Public Health and Colorado’s Regulation 43.

What we don’t do

We don’t design or stamp septic systems ourselves — that work is always completed by a licensed engineer. But we work closely with our engineering partners so you receive a complete, permit-ready package that passes Boulder County Public Health review the first time, without the back-and-forth that stalls a Boulder County build.

Where we work in Boulder County

We serve Boulder, Longmont, Nederland, Lyons and Ward and the surrounding Front Range foothills high country, out from Boulder. At 5,200–9,000 ft, Boulder County brings steep foothill and canyon lots, decomposed granite, and wildfire-interface ground — conditions our crews work in every week, not once a season.