Septic & OWTS · Arapahoe County
Septic system installation in Arapahoe County, Colorado
Tri-Lakes designs, permits, and installs onsite wastewater systems throughout Arapahoe County — from Aurora to Deer Trail. We build for metro edge giving way to open eastern-plains parcels, and we handle the Arapahoe County (Tri-County Health successor agency) permit and inspections start to finish.
Arapahoe County sits in the Denver metro / eastern plains at roughly 5,300–5,800 ft — ground that decides how a septic system has to be built.
Onsite wastewater on Arapahoe County lots means designing around metro edge giving way to open eastern-plains parcels. Those conditions rule out a one-size drainfield: the soil evaluation drives whether your lot takes a conventional gravity system, a pressure-dosed field, or an engineered treatment unit. We've built all three across the Denver metro / eastern plains.
Every install is permitted through Arapahoe County (Tri-County Health successor agency) under Colorado's Regulation 43. We prepare the stamped design, submit the OWTS permit, coordinate the county's inspections, and do the excavation in-house — so the same crew that reads your soil is the one setting your tank.
Towns we serve in Arapahoe County
- Aurora
- Byers
- Deer Trail
How your Arapahoe County project works, start to finish
Site Feasibility Report
We start at your lot. On a site visit we check property setbacks, read the slope, make a hands-on visual assessment of the soil, and cross-reference county and health-department code for anything that could constrain a system. You get a written feasibility report and a real plan for the site — typically within three business days.
Testing Proposal
With the feasibility done, we quote the next step — the soil profile testing — so you know the cost before going any further.
Soil Profile Pit Test
Once you move forward, we come back out and dig two soil profile pits to read the actual soil horizons on your lot. That's the hard data the design depends on — no guesswork, no assumptions.
Engineered System Design
We hand the soil data to a licensed engineer, who designs and stamps the septic system plans your county requires.
System Proposal
With stamped plans in hand, we price the materials and permitting off the design and give you a firm quote on the actual system.
Installation
Once the system is approved and paid, our crew installs it — tank, drainfield or treatment unit, and lines. The same crew that read your soil is the one setting your system.
Inspection & Final
We schedule the county's final inspection, backfill, restore the site, and hand you a system documented for the life of the property.
Septic in Arapahoe County — questions
Who permits a septic system in Arapahoe County?
Onsite wastewater permits in Arapahoe County are handled through Arapahoe County (Tri-County Health successor agency) under Colorado's Regulation 43. We prepare the design and submit the OWTS permit, then coordinate the inspections for you.
Can you install septic on Arapahoe County's terrain?
Yes. Arapahoe County sits at roughly 5,300–5,800 ft with metro edge giving way to open eastern-plains parcels. We design pressure-dosed, advanced-treatment, and engineered systems specifically for these conditions.
How much does a septic system cost here?
It comes down to your soil and the system type your lot requires. We start with a feasibility report and soil profile pits, then price the real system off the engineered plans — not a guess over the phone.
Septic work in the high country
Already have engineered septic or OWTS plans? Upload the PDF for an instant Colorado installation estimate, then have Tri-Lakes, a licensed Colorado OWTS installer, price and build the system.
Building or fixing a septic system in Arapahoe County?
Send your lot details and we'll map the soil test, design, Arapahoe County (Tri-County Health successor agency) permit, and install.
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