Walla Walla County Septic Permit Costs and Repair Rules

Sourced from the Walla Walla County Department of Community Health’s on-site sewage pages and its July 2025 permit application, Walla Walla County Code chapters 8.16 and 8.32 as published on the county’s code platform, county ordinances 496 and 502, RCW 70.05.074, and chapter 246-272A WAC — last checked August 2026. Where we could not source something, we say so.

What it costs

These come from Walla Walla County Code 8.32.020, and they match the figures printed on the county’s own permit application dated July 2025 — the code and the form agree, which is less common than it should be.

Failure is the cheap case here, and that is deliberate

Most Washington counties price a repair as a discount on a new permit. Walla Walla goes further, and the mechanism is in the code rather than in a fee table.

County code 8.16.040 rewrites subsection (3) of WAC 246-272A-0200 to read, in part:

“The Health Officer may develop the required information specified in subsection (2) of this section for simple gravity flow repairs to failing systems. All other installations, repairs, modifications, connections to, or expansions of an OSS shall require the information be prepared by a licensed septic designer or engineer.”

Read that first sentence carefully, because it is worth money. If your system has failed and the fix is a simple gravity repair, the county may do the design work itself. You are not obliged to go and hire a private designer for that specific case. The county’s permit application repeats the point in a one-line note.

Stack that with the rest of the replacement pricing and the arithmetic is unusual:

The site evaluation waiver is stated on the application itself: the site evaluation is an additional $200 and requires the owner to dig test holes, and the fee is waived for replacement applications.

But you cannot design a new system yourself

The other half of 8.16.040 is the restriction, and the county states the date plainly on its permitting page: effective July 1, 2023, all on-site sewage systems must be designed by a licensed On-Site Sewage System Designer or a Professional Engineer.

This is a live rule, not a legacy one. The amendment came in with Ordinance 496, adopted May 8, 2023, and the section was amended again by Ordinance 502 on April 21, 2025. Walla Walla has touched this part of its code twice in three years.

Two things it does not do, which are easy to get wrong:

• It does not stop you installing your own system. The permit application still offers “Resident Owner” alongside “Licensed Installer” as the installer. The restriction is on who designs, not on who digs.
• It does not apply to simple gravity repairs of failing systems, per the carve-out above.

The same subsection adds something worth knowing before you budget: the Health Officer performs the site and soil evaluation for all proposed installations, repairs, modifications, connections and expansions. That evaluation is a county service, which is why the $200 is unavoidable rather than something you can shop around for.

Lewis Peak: a calendar problem, not just a fee

If you are building in the Lewis Peak area, the county requires monitoring ports during the wet season to track the seasonal high water table. The county’s wording is unambiguous about the consequence: a permit will not be issued until wet season monitoring is completed. The fee is $500, which appears in the fee schedule as “winter observation.”

The fee is the small part. The constraint is that wet-season monitoring can only happen during the wet season, so a Lewis Peak project started in July is waiting on winter regardless of how quickly everything else moves. If you are buying land there, ask about this before you set a build date.

The 30-day clock most counties never mention

Printed on the county’s permit application is a statutory guarantee that rarely appears on a septic form anywhere:

Under RCW 70.05.074, the local health officer must respond within 30 days of receiving a fully completed application, and must respond that the application is approved, denied, or pending.

The load-bearing phrase is “fully completed.” An incomplete submission does not start the clock, which is the practical reason to get the design and the site evaluation squared away before filing rather than filing early to hold a place.

The appeal path is printed alongside it. If an application is denied, you may request a hearing before the Health Officer — in writing, within 30 days of the notice of denial — and the hearing must be set within 30 days of that request. If the appeal to the Health Officer fails, the decision may be appealed to the County Board of Health.

Test holes and the backhoe

The county schedules a site visit and test hole evaluation only after the site evaluation application and fee are in. You need at least one hole, six to seven feet deep, and the county expects the property owner or installer to coordinate with a backhoe operator to dig it.

If you dig before the specialist arrives, the holes must follow the Washington State Department of Health’s Guidelines for Test Pit Construction. More holes may be required at the specialist’s discretion, and remember the two-hour clock: past two hours on site, the meter runs at $100 an hour in quarter-hour increments.

Where the county’s paperwork is actually current

Worth noting after some of its neighbors: Walla Walla’s published documents are in good order. The permit application is dated July 2025, the site evaluation application May 2025, the designer and engineer list October 2025, and the licensed installer list is a 2026 document. The county’s fee code and its application form print the same numbers. If you want to check a figure here, the sources agree with each other.

If you are selling in Walla Walla County

We found no local rule requiring a septic inspection at property transfer. County code chapter 8.16 covers applicability, adoption, permits, installation, certification, food service maintenance, appeals and penalties — and contains no language about sale, transfer or conveyance at all. We also found no mention anywhere on the county’s pages of the statewide change under WAC 246-272A-0270 that takes effect February 1, 2027.

Chapter 8.16.020 adopts WAC 246-272A and 246-274 by reference, so the state framework applies here by default and the county then amends specific sections of it. That is the structure to watch: if Walla Walla responds to the 2027 change, the likely place it shows up is a new amending section in 8.16, not a press release.

What we could not source

• Any county statement about the February 1, 2027 statewide transfer inspection. Nothing on any page we checked, and nothing in chapter 8.16.
• A published operation and maintenance provider list. The county certifies installers, pumpers and O&M specialists, and publishes installer and pumper lists, but we did not find a separate O&M list.
• The map or legal boundary of the Lewis Peak area. The requirement is stated but we did not find a published boundary; if you think you may be inside it, ask.
• What the Health Officer charges, if anything, for developing a simple gravity repair design. The code permits it; no separate fee line appears for it.
• How many on-site systems are in the county. Not published anywhere we could find.

The practical bits

Sources

• Walla Walla County Department of Community Health, Onsite Permitting Process — dch.wwcowa.gov
• Walla Walla County Department of Community Health, On-Site Sewage Land Use — dch.wwcowa.gov
• Walla Walla County Department of Community Health, OSS Failure and Replacement — dch.wwcowa.gov
• Application for Onsite Sewage Disposal Installation Permit, July 2025 — dch.wwcowa.gov
• Walla Walla County Code 8.32.020, sewage program fees (Ord. 472, October 8, 2018) — library.municode.com
• Walla Walla County Code 8.16, sewage disposal regulations, including 8.16.040 (Ord. 496, May 8, 2023; Ord. 502, April 21, 2025)
• RCW 70.05.074; WAC 246-272A and WAC 246-274; WAC 246-272A-0270, inspection at property transfer