What a full inspection covers
A thorough OWTS inspection works from the house outward, and each stop has its own failure modes.
The tank. Locating and opening it, pumping it down, and checking the walls for cracks, the inlet and outlet tees or baffles for damage, and the liquid level for signs of a backup or a leak. A tank inspected while full hides most of what an inspector needs to see, which is why both Jefferson County and Boulder County require the tank pumped and inspected as part of a transfer inspection, per the Jefferson County Use Permit Program and Boulder County's property transfer certification instructions.
The distribution network. The distribution box or pressure lines that split flow across the soil treatment area, checked for settling, root intrusion, and uneven flow, the quiet culprits behind one soggy corner of an otherwise healthy field.
The soil treatment area. The field itself, read from the surface: soggy ground, surfacing effluent, oddly green strips in dry weather, or lines crushed under a driveway or shed that arrived after the system did.
The paper trail. The system's permit record with the county, which establishes what was approved, when, and at what capacity. A four-bedroom house on a system permitted for two bedrooms is a finding, even when everything underground looks fine.
The product is a written report. In a sale, that report is what the county reviews before issuing its document. Outside a sale, it is the owner's baseline for maintenance and budgeting.
When an inspection makes sense
Selling. In Jefferson, Larimer, and Boulder counties, the inspection is the foundation of the county transfer document, with its own deadlines; the transfer inspection page has the county-by-county rules.
Buying. A buyer can order an independent inspection even where the seller supplies the county paperwork. In Larimer County the acceptance document is valid until the closing date or for up to 12 months, whichever comes first, so check how old the underlying inspection is before relying on it.
Troubleshooting. Slow drains, sewage odor, or wet ground over the field are reasons to inspect now rather than guess.
Setting a baseline. After moving in, or before adding a bathroom or bedroom, an inspection plus a routine pumping establishes what you own and what it can carry.
Who can inspect, county by county
Larimer County requires a county-licensed inspector holding a current NAWT inspector certification, and the inspection report goes straight to the Larimer County Department of Health and Environment, per the county's transfer of title page. Jefferson County requires an approved inspector, with the tank pumped and inspected, under its 2018 OWTS regulations. Boulder County requires a licensed inspection feeding the Property Transfer Certificate issued by Boulder County Public Health.
In all three counties the inspector choice is yours; the county sets the qualifications, not the pick. We connect you free with an independent local septic contractor who works in your county, and the decision on who to hire stays with you. That arrangement, and who pays us, is spelled out on how we make money.
What to have ready before the inspector arrives
The visit goes faster, and costs less in dig time, when the paperwork and the lids are findable. Pull whatever records exist: the county permit, an as-built sketch showing tank and field locations, past pumping receipts, and any prior inspection reports. If the tank lids are buried, locating and exposing them ahead of the appointment saves probing and shovel work at the inspector's hourly rate. Know where water goes when it leaves the house, including any graywater lines or floor drains that were added over the years. And in a sale, bring the closing date: in Larimer County the report goes to the county for review, and in Jefferson County the application clock runs in working days, so the inspector needs to know what deadline the fieldwork is feeding.
The well water wrinkle in Jefferson County
Where a well serves the property, Jefferson County requires a well water sample tested for total coliform and nitrate before a use permit issues, per the Use Permit Program page. Foothills properties around Evergreen and Golden commonly pair a well with an OWTS, so the sample belongs on the same calendar as the inspection, not as an afterthought once the closing date is set.
What an inspection costs
Plan on a few hundred dollars for the inspection itself, quoted to your site, access, and tank configuration. In Larimer County, one Loveland contractor publishes transfer inspections starting at $475 per system, with more for travel time, difficult access, or road conditions (Johnston Sanitation, contractor-published). County program fees, where a transfer document is involved, are separate; the statewide OWTS framework and county contacts are collected by the Colorado Department of Public Health and Environment.