Septic inspections
Closing on a house outside town? An inspection tells you whether the system is healthy and whether it matches what the county approved.
A standard home inspection rarely covers the septic system. A separate septic inspection opens the tank, checks the parts that keep solids in place, and looks for signs the drainfield is struggling. For a buyer, it's the difference between knowing and guessing about one of the most expensive systems on the property.
What does a septic inspection look at?
- Finding the tank and drainfield and comparing them with the county permit
- Sludge and scum levels, and the condition of the tank walls and lids
- Inlet and outlet baffles and any effluent filter
- The pump or siphon chamber, floats and alarm on pressure-dosed systems
- Wet spots, odors or surfacing effluent over the field
Pull the county records first
The Flathead City-County Health Department handles septic permits, and you can ask what a property is approved for by submitting a land research request. Existing permits can also be looked up through the county's GIS portal. For lots under 20 acres, the approval may come from a Certificate of Subdivision Approval (COSA) issued by Montana DEQ, which the county can help you get a copy of. Compare the approved number of bedrooms with what's actually in the house.
Planning an addition, guesthouse or RV pad?
The county says an addition or loft has to keep the total bedroom count within what your existing septic permit allows. A guesthouse or a single RV site is treated as a second dwelling, so the property has to be approved for one, and two or more RV sites trigger state subdivision review. An inspection plus a records check tells you where you stand before you draw plans.
Timing for a sale
Book the septic inspection early in your inspection period. If something turns up, you'll want time to get a repair quote, and in spring a saturated drainfield can look worse than it does in late summer, so ask the inspector how the season may affect what they see.
Pricing comes from the septic company after it learns about your property and, for repairs or new systems, looks at the site and the county paperwork. We don't quote prices, and a figure given over the phone before anyone has seen the system is only a ballpark.
Where we connect you with help
Common questions
Does a regular home inspection cover the septic system?
Usually not. Most home inspectors stop at the plumbing inside the house. Hire a septic company for a separate inspection.
How can I find out what a Flathead property's septic system was permitted for?
Submit a land research request to the Flathead City-County Health Department's Environmental Health office, or look up existing permits on the county GIS portal.
Related services
More background: Flathead County septic guide.
Toilets slow, yard wet over the drainfield, or a pump alarm sounding?
Call and we'll put you in touch with a septic company that serves the Flathead Valley.