Septic Inspection in Eastern Washington and North Idaho: Intervals, Contents and Who May Inspect

Washington requires a routine septic inspection at least every three years for a tank with a gravity drain field and every year for other systems. A provider on the health district's list can do it, and some districts let owners inspect their own system after watching the district's training videos. The report goes to the health district. Idaho requires annual service on advanced treatment units.

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Last reviewed: October 26, 2026

What a routine septic inspection is

A routine inspection, called an operation and maintenance inspection in the rules, checks whether the whole system is working, needs maintenance, and complies with the rules and the permit. It is a different visit from a home-sale inspection, covered on the home-sale inspection page, and different from a pump-out, covered on the pumping page.

How often Washington requires it

WAC 246-272A-0270(1)(e) sets the intervals. The owner must obtain an inspection by a maintenance service provider authorized by the local health officer at least once every three years for a system consisting solely of a sewage tank and a gravity drain field, unless the health officer sets a shorter interval. All other systems must be inspected annually. The owner submits the results to the health jurisdiction on an approved form. EPA gives the same pattern: at least every three years for an average household system, and generally once a year for alternative systems with electrical float switches, pumps or mechanical parts.

SRHD puts it in a list: conventional gravity systems every three years, all other systems annually, and holding tanks annually. SRHD says owners receive a reminder postcard, and that the completed Operations and Maintenance Inspection Report Form is due back to SRHD within 60 days of the inspection, weather permitting.

What an inspection must include

WAC 246-272A-0260(5) sets the minimum. The inspection must evaluate:

All sewage tanks, including baffles, effluent filters, tank contents such as water level, scum, sludge and solids, water tightness and general structural condition.
All lids, accesses and risers.
The system and the reserve area, for signs of failure or anything that could affect how the system works, is operated or is repaired.
Other components such as distribution boxes.
The record drawing and related documents, including previous reports, to confirm the system is operating as designed.
Any proprietary treatment products, following the maker's operation and maintenance manual.

A provider may add more. A local health jurisdiction may require an additional report or more information.

Who may inspect

WAC 246-272A-0340 requires maintenance service providers to be approved by the local health officer before they work in a jurisdiction. In Spokane County, SRHD permits O&M providers every year. The permit process includes an application, a fee, an exam at SRHD, and a copy of a current Washington Labor and Industries contractor license. SRHD publishes the list of permitted O&M providers and says it does not endorse them. The Northeast Tri County Health District posts a list of its certified operation and maintenance service providers on the septic contractors page.

The Department of Health also says some local health agencies let owners do certain inspections themselves. WAC 246-272A-0340(3) allows a health officer to create a homeowner inspection certification process. SRHD says an owner who wants to inspect their own system should watch the Department of Health training videos and read the maintenance manual for their system. Ask your district whether an owner inspection is accepted before you rely on it.

Idaho

The sources used for this page set out the three-year and annual intervals in Washington's rule. For an ordinary Idaho tank and drain field, ask the Panhandle Health District what inspections it expects. Idaho DEQ does set a rule for extended treatment package systems, the aerobic units: each needs at least one operation and maintenance event a year, with an annual report to the health district by July 31 each year, and the work must be done by a certified service provider. IDAPA 58.01.03 section 006 creates the service provider permit for that work.

What an inspection report is good for

The report documents the condition of the system and sets a baseline. It is the record to hand to the next owner. In Spokane County it also matters for a sale: SRHD says an O&M inspection completed by a permitted provider within the previous 12 months can support an exemption from the transfer inspection, and that failing to maintain a current operational permit may delay the transfer inspection that starts in 2027.

How to prepare

Find the lids, and expose them if you can.
Gather the permit, the as-built drawing and the last report.
Note the last pumping date and any repairs.
Say what type of system you have: gravity, pressure distribution, mound, sand filter or aerobic unit.
Ask what the visit covers and whether pumping, if recommended, is a separate charge.
Ask when the report will be filed with the district, and who files it.

Questions to ask an inspector

The Department of Health suggests asking a maintenance provider about the estimated cost and whether it includes health department fees, what the inspection includes and leaves out, whether there is an extra charge to dig up the lids, and whether the company knows how to service your type of system.

What changes the price

This site does not quote prices. Lid depth, system type, tank count, access and travel all change an inspection visit, and so does the fee the district charges to file the report. See the pumping cost guide.

Published fee information

The Northeast Tri County Health District's fee schedule, effective January 1, 2026, lists $67 for operation and maintenance report review and recording. That is a district fee, separate from any provider's charge. This site has no sourced inspection price from a company, so it gives none. Ask each provider what the visit includes and costs.

Reasons to trust this page

The interval, contents and approval rules come from WAC 246-272A-0260, 0270 and 0340.
District details come from SRHD and the Northeast Tri County Health District pages.
Idaho details come from Idaho DEQ and IDAPA 58.01.03.
No inspector or price is recommended.

Frequently Asked Questions

How often does a septic system need an inspection in Washington?

At least once every three years for a system made only of a tank and a gravity drain field, and annually for every other type, unless the local health officer sets a shorter interval. The report goes to the health district on an approved form. Holding tanks in Spokane County are inspected annually.

What does a septic inspection include?

Under WAC 246-272A-0260(5), the inspector evaluates the tanks, baffles, effluent filters, tank contents and water tightness, plus lids, accesses and risers, the system and reserve area for signs of failure, distribution boxes, the record drawing and any proprietary products. The inspector follows the maker's manual for those products.

Who is allowed to do a septic inspection?

A maintenance service provider approved by the local health officer. In Spokane County that means a permitted O&M provider on the SRHD list. In Stevens, Pend Oreille and Ferry counties, it means a certified provider on the Northeast Tri County Health District list. Some districts may accept owner inspections, so ask.

Is pumping the same as an inspection?

No. The Department of Health says pumping does not replace an inspection. A maintenance provider should inspect the system and decide whether pumping is needed. A pump-out can be part of the same visit, but the inspection report with its required contents is a separate record for the health district.

Does Idaho require a routine septic inspection?

This page found Washington's intervals, not a matching statewide Idaho interval for an ordinary system. Idaho DEQ does require annual operation and maintenance on aerobic extended treatment units, with a report by July 31. For anything else, ask the Panhandle Health District what applies to your property.

Sources

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