Well, Septic, and Form 22S: The Rural WA Inspection Items Agents Miss

Why rural WA deals die at inspection

You write a clean offer on a 2.5-acre listing in Graham or Maltby, get mutual acceptance, and feel good. Then the general inspector flags a septic system the contract never gave your buyer a path to test or pump, and a well no one ordered a flow or potability test on. Now you are renegotiating from a weak position, or watching the deal collapse, because the addendum that should have covered it was never attached.

Private well and on-site septic are not edge cases in Western Washington. They are the default across rural and river-valley Snohomish and Pierce parcels — the large-lot submarkets where city water and sewer simply do not reach. The fix is not heroics at inspection. It is knowing which NWMLS forms attach at offer, and how each contingency clock runs alongside the general inspection window.

SENTINEL flags well and septic exposure the moment you pull a rural parcel, so the right addenda are on your radar before you write — not after the inspector finds the tank.

What Form 22S actually does (and its well-water companion)

NWMLS Form 22S is the Septic Addendum. It is what makes on-site sewage its own contingency rather than a footnote buried inside the general inspection. The seller represents what they know about the system — type, age, capacity, last pumping, any known repairs or failures — and the form gives the buyer a defined right to inspect the septic and, in most cases, to require it be pumped as part of that inspection. That pumping-and-inspection right is the leverage; without 22S, a buyer relying only on Form 35 may have no clean contractual hook to demand it.

Well water rides on a separate form. Private-well coverage runs through Form 22R, the Well Water Addendum, which sets up the buyer's right to flow and water-quality testing. When a well is shared, the optional well-sharing clauses (carried via the Optional Clauses Addendum, Form 22D) and the recorded shared-well agreement come into play. The takeaway: do not assume one addendum covers both. A rural listing with a well and a septic system typically needs Form 22S and Form 22R, not a single catch-all.

These are contract forms, so treat the form-specific deadlines and rights as governed by the addendum language itself, not by the general inspection default. — Not legal advice. Verify with your broker or a WA-licensed attorney.

How the contingencies stack on the inspection window

Here is where agents lose deals: they treat the general inspection contingency as the only clock. On a rural property there are several running at once. Form 35, the Inspection Addendum, carries a default of 10 calendar days from mutual acceptance. Because that period is longer than five days, WA's day-counting rule (RCW 1.16.050) makes it calendar days, not business days — weekends and state holidays count. The septic inspection and pumping under Form 22S, and the well flow and potability testing under Form 22R, run on the timelines those addenda specify, and they often need to be scheduled and completed inside the same general window.

That compression is the trap. A septic inspector and pumper have to be coordinated, and a certified lab needs processing time. Compare those lead times with the periods actually entered in the executed agreement and addenda before the offer is signed.

SENTINEL can calculate supported dates from the verified trigger dates and periods you enter. It cannot infer missing addenda, delivery events, amendments, or custom language, so compare the output with the signed file and brokerage calendar.

The septic side: WAC 246-272A and a failed drainfield

On-site septic in Washington is governed by WAC 246-272A, the state Health Department rule for on-site sewage systems — that rule is the reason Form 22S exists. Many local health jurisdictions require an inspection at the time of property transfer, and a tank pump-out is commonly part of that inspection or required outright at sale. The functional standard for the deal: a current, passing inspection report from a certified inspector, plus a pumping record, with any deficiencies identified before closing rather than discovered by your buyer the first wet winter after.

A failed drainfield is the negotiation that reshapes the whole transaction. Replacement is not a small repair — a new or expanded drainfield on a difficult site can run well into five figures, and a failing system in a sensitive area may trigger design and permitting before anyone can break ground. When that report comes back, the conversation moves off list price entirely and onto who funds the repair, whether the buyer's lender will even close on a non-functioning system, and how long the permit pushes the timeline. Get the septic inspected early enough that you are negotiating the drainfield, not begging for a closing extension.

— Verify against the current MLS listing and the transaction documents before advising your client.

The well side: flow, potability, and shared-well agreements

A private well gets tested two ways, and agents routinely order only one. Flow (quantity) testing measures whether the well produces enough sustained gallons-per-minute to actually serve the household — a low-yield well is a real deal-killer, especially on larger lots or for buyers planning irrigation or livestock. Potability (water-quality) testing checks whether the water is safe to drink, with coliform bacteria and nitrate the standard panel. Both matter; a well can be plentiful but contaminated, or clean but too weak. FHA and VA financing typically require a current water-quality result and a state well report, so on a financed rural deal these are not optional niceties.

Shared wells add a layer most general inspectors will never raise. When two or more parcels draw from one well, there should be a recorded shared-well agreement spelling out cost-sharing, maintenance responsibility, and water-rights allocation — and because it is recorded, it binds future owners, including your buyer. Pull it during the title and inspection window, read who pays for what, and confirm it actually runs with the land. An unrecorded handshake between neighbors is not protection; it is a future dispute your buyer inherits.

— Not legal advice. Verify with your broker or a WA-licensed attorney.

County notes: SnoCo and Pierce rural and river-valley parcels

In Snohomish County, well and septic are the norm once you leave the city-water footprint — east and rural pockets like Maltby and Clearview, plus the river-valley and large-lot parcels north and east of Everett. River-valley ground brings its own overlay: high water tables and flood exposure can affect both drainfield siting and well-head protection, which is exactly the kind of detail a general inspection glosses over. See the Snohomish County hub at /wa/snohomish for the submarkets where these systems dominate.

Pierce County runs the same pattern across its rural south end — Graham, Roy, McKenna, and Eatonville commonly sit on 2.5-acre-plus lots with private well and septic. These are the listings where ordering the septic inspection and the well flow-and-potability panel up front separates a clean close from a two-week fire drill. The Pierce County hub at /wa/pierce covers those areas. On any rural file in either county, attach Form 22S and Form 22R at offer, schedule the inspections early in the general window, and you stop losing deals to systems the contract never covered.