Island County, Washington: septic system inspection at sale
Checked on November 9, 2026 against the official rule. Rule set by Island County Public Health.
General information, not legal advice. This is our summary of the official rule as we read it. The ordinance or code and the health department decide: confirm with them before you list, sign or close.
The rule
Washington also has a statewide rule: see the Washington page. Where both apply, follow both.
| Question | What the official text says |
|---|---|
| What is required | Septic inspection by Island County Licensed Maintenance Service Provider, report on On-Site Sewage Inspection Report form via Online RME Source: islandcountywa.gov |
| Triggered by | transfer / sale Source: islandcountywa.gov |
| Deadline | before closing; ideally at time of offer Source: islandcountywa.gov |
| Who arranges it | seller Source: islandcountywa.gov |
| How long a report is valid | conventional systems inspected in past 3 years, alternative in past 1 year are compliant Source: islandcountywa.gov |
| Fee | not set by county; providers charge roughly $100 to $500 (2026 fee schedule) Source: islandcountywa.gov |
| If the system fails | Report says acceptable, needs corrections or failed; seller and buyer negotiate repairs Source: islandcountywa.gov |
| Who may inspect | Island County licensing. official page (islandcountywa.gov) Source: islandcountywa.gov |
| In force since | 2008 Source: islandcountywa.gov |
This is our summary of the official rule as we read it. The ordinance or code and the health department decide: confirm with them before you list, sign or close. Rule set by: Island County Public Health.
In force since 2008 (as the official text states).
Checked on November 9, 2026: read on the official site.
Published costs
What the official fee schedule or guide for Island County says, with the year it applies to. The other 1 item published in Washington are listed for comparison; they are different items, so we do not average them.
| Jurisdiction | Item | Amount | Year | Source |
|---|---|---|---|---|
| Island County (this rule) | septic inspection at sale (provider charges) | $100 to $500 | 2026 | islandcountywa.gov |
| Skagit County | inspection rebate for qualifying residents | up to $100 | 2026 | skagitcountywa.gov |
Inspectors, pumpers and labs set their own prices on top of these; the official source is the one that counts.
Compared with other Washington rules
- In force since 2008: the 2nd oldest of the 4 Washington local rules whose start year we could read. Oldest: Skagit County (2006), Island County (2008), Clallam County (2010).
Our census of official rules, checked November 9, 2026; start dates as the official text states them.
Private wells in Island County
In 2015 about 11,558 of Island County’s 80,593 residents (14%) got their drinking water from a private well, by the USGS estimate. That is the 31st highest share of the 39 Washington counties in the USGS table, and the 23rd highest number of private-well users.
As we read it, this rule covers the septic system, not the well.
Source: USGS county water use 2015 (Dieter et al., 2018). Ranks count the Washington counties in the USGS table (1 = highest).
Soils and septic systems here
USDA soil surveys rate 100% of Island County’s rated land “very limited” for a conventional septic drain field, 0% “somewhat limited” and 0% “not limited”, the 2nd highest “very limited” share of 12 Washington counties with survey data. The most common limits: a high water table (saturated soil near the surface) on 66%; poor filtering (coarse sand or gravel) on 52%; fast seepage below the field (risk to groundwater) on 48%.
Where soils are limited, inspections more often find drain fields that sit in seasonally wet soil, and replacement systems are often mounds or other engineered designs. A county-wide rating, not a test of one lot: a site evaluation decides. Source: USDA NRCS Soil Survey Geographic Database (SSURGO), via Soil Data Access, rating “ENG - Septic Tank Absorption Fields”, read November 15, 2026.
Certified labs nearest to Island County for a well water test
Labs on the Washington certified drinking-water list that the list marks as taking samples from homeowners or outside clients, certified for coliform bacteria, nearest first. All of them are outside Island County.
| Lab | Town | Distance | Certified on the list for |
|---|---|---|---|
| Eurofins DW and WW West, Washington Laboratory | Burlington, WA | 24 miles | coliform bacteria, nitrate |
| Spectra Laboratories - Kitsap, LLC | Poulsbo, WA | 24 miles | coliform bacteria, nitrate |
| Freshwater Analytical Labs, LLC | Arlington, WA | 28 miles (approx.) | coliform bacteria |
Source: WA Ecology - Environmental Laboratories Accredited for Drinking Water Analyses (with scopes) (Information current as of 11/13/2026; read November 15, 2026). Straight-line distance from the centre of Island County (the average of its Census ZIP-area points); “approx.” = lab placed at its ZIP centre. Call the lab first: lists do not say which household tests each lab takes or what it charges.
Nearest other sale-time rules
Buying or selling near a county line? These are the closest other local rules in our census to Island County.
| Rule | State | Distance | Covers | Checked |
|---|---|---|---|---|
| Skagit County | Washington | about 28 miles | Septic system | November 9, 2026 |
| King County | Washington | about 44 miles | Septic system | November 9, 2026 |
| Pierce County | Washington | about 68 miles | Septic system | November 9, 2026 |
| Clallam County | Washington | about 71 miles | Septic system | November 9, 2026 |
| Thurston County | Washington | about 84 miles | Septic system | November 9, 2026 |
Straight-line distance between county centres (the average of each county’s Census ZIP-area points). Townships, villages and health districts are placed at the centre of their county.
All rules: by state · Washington.