On September 1, Seattle’s permitting agencies published two updates within an hour of each other. One was a housekeeping note on the 2026 Stormwater Code. The other announced that Seattle Public Utilities now reviews your sanitary and side sewer design at the same time SDCI reviews your building permit. Read separately they look like process minutiae. Read together they are the biggest change to how Seattle handles private drainage in years — and the burden lands squarely on property owners.
The Seattle Department of Construction and Inspections posted a status update on the 2026 Stormwater Code and Stormwater Manual, noting they have now been in effect for several months. The post directs applicants to use the new Stormwater Plan and, where required, the Small Construction SW Control Soil Management Standard Plan, both available on the SDCI Stormwater Code webpage. It also flags new “Stormwater Code 101” and “2026 Code Update” training videos, and a run of virtual question-and-answer sessions.
The second post, published the same day, is the one with teeth. Seattle Public Utilities has implemented a new process to review on-site sanitary sewer design and off-site points of connection for drainage and wastewater in parallel with SDCI’s building permit review — a change SPU says will mean fewer building permit revisions after issuance, faster issuance of side sewer permits for new construction, and less confusion during design and construction.
The review happens in the Seattle Services Portal under a record type called IPR. The records carry the format SPUE-IPR-26-XXXXX and are generated automatically for any project involving 750 square feet or more of land‑disturbing activity. Each IPR record is created from and linked to the construction permit.
The single most important thing to understand about them: an IPR record is not a permit and does not replace a construction or side sewer permit. It is the channel through which SPU sends review comments and through which you upload revised plans and required legal documents, so that when you do submit for the side sewer permit, it goes through.
| What the IPR record does | What it does not do |
|---|---|
| Delivers SPU’s required revisions to sanitary and storm side sewer design, including approved discharge points for drainage and wastewater | Authorize any construction. It is explicitly not a permit |
| Holds the reviewed Stormwater Plan that SPU attaches after review | Replace the side sewer permit or the construction permit |
| Collects required recorded legal documents — Memorandum of Drainage Control, Side Sewer Easement Agreement, Side Sewer Joint Use and Maintenance Agreement, Side Sewer Release and Indemnification Agreement | Cover on-site stormwater management or drainage lines on private property — those revisions still go to the construction permit |
| Runs concurrently with SDCI building permit review rather than after it | Get created for projects under the 750-square-foot land-disturbance threshold |
SPU is fielding questions on the change at sidesewerinfo@seattle.gov, and maintains a full reference list of the documents that must be recorded for side sewer work.
SDCI’s September 1 guidance singles out the Preliminary Assessment Report and asks applicants to read it carefully, because it now carries detailed information from both SDCI and Seattle Public Utilities covering the stormwater and wastewater requirements for a project. The stated intent is to front-load as much information as possible before plans are submitted.
That is a meaningful shift. Historically, an owner could get a building permit issued and only discover the side sewer constraints — where the connection is allowed, whether an easement has to be recorded, whether a shared lateral triggers a joint use agreement — well after design was locked. Those discoveries are the source of most expensive mid-project redesigns in Seattle drainage work. Moving them into the PAR and into a concurrent SPU review is the fix.
Both September 1 posts are written for the permit desk. They tell you how to get approval. Neither addresses what happens on the day after approval — and that is where the real cost sits.
The direction of Seattle’s stormwater regulation for a decade has been to keep more water on the parcel that generated it. Bioretention cells, permeable paving, drywells, detention, dispersion trenches. Every one of those is a facility that clogs, silts, compacts, or roots over. And every one of them is privately owned and privately maintained the moment the inspector signs off.
Add the sanitary side to that picture and the exposure compounds. The same SPU review that now approves your discharge point also documents the easements and joint-use agreements attached to your side sewer — which means the paperwork defining who is responsible for that private pipe is being created and recorded at permit time. Owners who never read it will find out what it says during a backup.
Homeowners doing a DADU, addition or major hardscape. The 750-square-foot land-disturbance trigger is not a big number. A detached accessory dwelling unit with a driveway apron clears it comfortably. Those projects now generate an IPR record and a concurrent SPU sewer review whether or not the owner expected one.
Small commercial and multifamily owners. A new drainage facility on a small commercial site is an asset with an annual maintenance obligation nobody budgeted for. Silted bioretention and blocked area drains show up first as ponding in a parking area and later as water intrusion.
Anyone on a shared lateral. Older Seattle blocks are full of two-and-three-house private runs. The joint use and maintenance agreement SPU now collects at review time is the document that decides who pays when that run fails. Our Ballard Side Sewer Report maps how common those arrangements are in one representative neighborhood.
“The parallel review is a good change — it catches the connection problem while the design can still move. What worries me is the second half. We’re handing people a drainage system on their own property and a recorded agreement about their own sewer line, and nobody hands them a maintenance schedule to go with it. Five years later I’m in the crawlspace explaining why a bioretention cell that was never cleaned is now the reason the foundation is wet.”
The SDCI stormwater review team has posted “Stormwater Code 101” and “2026 Code Update” training videos in the training section at the bottom of the SDCI Stormwater Code page. SDCI describes them as useful whether you are new to stormwater management or experienced with complex submissions.
The team is also running virtual question-and-answer sessions from 3–4 PM. The September 2 and September 9 sessions have been held; the remaining general session is September 16, followed by a September 22 session specifically for engineers. Meeting links are on the SDCI post, and anyone with a stormwater question is invited to whichever session fits.
This follows our earlier coverage of what the 2026 Seattle stormwater code means for homeowners and businesses. For a broader look at how drain and sewer service works in this market — what each method does, when it is the right one, and what it should cost — see our Seattle drain cleaning guide. Commercial owners can start with commercial drain cleaning in Seattle, and property-level questions are collected in our Seattle drain and sewer FAQ.
Camera inspection, jetting and documented as-built condition for Seattle property owners, developers and managers across King and Snohomish counties.
Book an InspectionIt is the Seattle Services Portal record type Seattle Public Utilities uses for its new parallel review of on-site sanitary sewer design and off-site points of connection. Records follow the format SPUE-IPR-26-XXXXX, are created from and linked to the construction permit, and are generated automatically for projects with 750 square feet or more of land-disturbing activity.
No. SPU states directly that IPR records are not permits and do not replace construction or side sewer permits. They exist so SPU can share review comments and so applicants can upload revised plans and required legal documents ahead of a successful side sewer permit submittal.
SPU communicates required revisions to sanitary and storm side sewer design, including approved discharge points, along with required recorded documents such as the Memorandum of Drainage Control, the Side Sewer Easement Agreement, the Side Sewer Joint Use and Maintenance Agreement, and the Side Sewer Release and Indemnification Agreement.
Revisions to on-site stormwater management or drainage lines on private property continue to go to the construction permit. Requested documents for the sanitary and storm side sewer review are uploaded to the Seattle Services Portal against the IPR record.
Yes. The SDCI stormwater review team is running virtual Q&A sessions from 3–4 PM. The September 2 and September 9 sessions have been held. One general session remains on September 16, plus a September 22 session for engineers. Side sewer questions can also be sent to sidesewerinfo@seattle.gov.
The Drain Authority is a drain and sewer specialist serving King and Snohomish counties from Ballard. This article is reporting and general information, not legal advice on any recorded agreement.
