Stormwater permits in City of Sammamish: fees, timeline & requirements (2026)
Everything you need to know about pulling a stormwater / drainage permit in City of Sammamish, Washington — when one is required, what it costs, how long review takes, what documents are required, and which inspections you can expect. Cited to Apply via MyBuildingPermit.com..
Free lookup, no account needed — your lot polygon, zoning, setbacks and overlays, cited to City of Sammamish's source.
When does a stormwater / drainage need a permit in City of Sammamish?
Ecology's Stormwater Management Manual for Western Washington (SWMMWW, 2024 edition) is the state floor. A municipal stormwater permittee may instead adopt a REGIONAL manual Ecology has determined equivalent, and most do — some counties publish their own, some cities publish their own, and others adopt Ecology's directly. WHICH MANUAL APPLIES IS A PER-JURISDICTION FACT and it changes the numbers: review thresholds for new plus replaced impervious surface and for land-disturbing activity differ between manuals, so read this jurisdiction's own adopting chapter before quoting one. Critical-area and closed-basin parcels get stricter review under every manual.
From City of Sammamish's own code
“All clearing and grading activities must be associated with an approved land use and exceptions do not apply to properties that are undeveloped and do not have an approved land use. No clearing and grading activities may occur on undeveloped properties without a permit associated with an approved land use. On sites without an approved land use the removal of hazardous trees, invasive species, and noxious weeds is allowed with issuance of a clearing and grading permit.”Source ↗verified 2026-05-29
Required submittals
- drainage report (full or simplified)
- site plan with impervious calc
- BMP / facility detail
- geotech if infiltration claimed
Inspection sequence
- pre-construction (BMPs in place)
- facility installation
- final stabilization
Contractor specialties needed
general
Who can do this work in City of Sammamish?
Kolmo Construction is a licensed Washington general contractor — KOLMOL*753JS, active through April 10, 2027, bonded and insured — working throughout City of Sammamish and King County. Kolmo prepares the drawings and submittals, files the stormwater / drainage permit with Apply via MyBuildingPermit.com., carries the project through review and inspections, and performs the construction. Call (206) 410-5100 for a City of Sammamish stormwater / drainage quote.
Notes & caveats
Issuing body is city public works / county DPER, often parallel to the building permit. On-site infiltration / detention required where infeasible to discharge to municipal storm. Critical-area parcels (steep slope, salmon-bearing watercourse) get more conservative review.
How to apply yourself
- 1. Confirm your parcel's zoning & overlays. Run an address lookup for your City of Sammamish stormwater / drainage — we'll pull your specific lot polygon, zoning, setbacks, and any shoreline/ECA/historic overlays.
- 2. Assemble submittals (4).
- 3. Submit through the city portal: Apply via MyBuildingPermit.com. ↗
- 4. Track review. Respond to reviewer comments promptly.
- 5. Pay issuance fees (Drainage review fees are commonly tiered by project size in the city's fee schedule. Apply via https://mybuildingpermit.com.) and pick up the permit. Inspection card travels with the job.
Or have Kolmo do it
We pull stormwater / drainage permits in City of Sammamish every month. We prepare the drawings and submittals, file with Apply via MyBuildingPermit.com., handle reviewer comments, and build the project.
Licensed WA general contractor KOLMOL*753JS · bonded & insured
Stormwater permits in City of Sammamish — FAQ
When does a stormwater / drainage need a permit in City of Sammamish?
Ecology's Stormwater Management Manual for Western Washington (SWMMWW, 2024 edition) is the state floor. A municipal stormwater permittee may instead adopt a REGIONAL manual Ecology has determined equivalent, and most do — some counties publish their own, some cities publish their own, and others adopt Ecology's directly. WHICH MANUAL APPLIES IS A PER-JURISDICTION FACT and it changes the numbers: review thresholds for new plus replaced impervious surface and for land-disturbing activity differ between manuals, so read this jurisdiction's own adopting chapter before quoting one. Critical-area and closed-basin parcels get stricter review under every manual.
How much does a stormwater / drainage permit cost in City of Sammamish?
Current fee per the City of Sammamish fee schedule: Drainage review fees are commonly tiered by project size in the city's fee schedule. Apply via https://mybuildingpermit.com.. Plus ancillary plan-review/tech-surcharge fees per city schedule.