Development Review, Permitting, and Engineering Resources

Are you developing in the City of Sammamish? If you are applying for a land use permit, building permit, or clearing and grading permit, drainage review may be required. Any work or impact to traffic in public right-of-way must obtain a Right-of-Way permit.

The Development Review Engineering team reviews, permits, and inspects the construction of new roads, storm water utilities, right-of-way improvements, and erosion control associated with the development of private property. For more information on the land use and permitting process, visit the Department of Community Development web page.

Public Works Standards and Design Requirements

Public Works Standards

Engineering Plans Standard Notes (Drainage, Grading and Erosion, Roadway)

Surface Water Design Manual and References

Sammamish Addendum to the 2016 KCSWDM
2016 King County Surface Water Design Manual
2016 King County Surface Water Design Manual – Errata
Note: Projects vested prior to January 1, 2017 reference the Archived Requirements section at the bottom of this page.

See the Maps and GIS Data webpage for flow control, water quality, landslide hazard drainage areas, and erosion hazard areas maps.

Important notice about projects permitted under earlier versions of the SWDM

Per requirements in Sammamish's Phase II Municipal Stormwater Permit (effective date August 1, 2019), projects permitted under the 2016 SWDM that applied prior to July 1, 2022 and have not started construction by July 1, 2027, and projects permitted under earlier versions of the SWDM that applied prior to January 1, 2017 and have not started construction by January 1, 2022, must be revised to comply with the requirements of the 2021 SWDM, or subsequent versions as directed by state regulations. Revisions will need to be approved by the Department of Community Development.

*“Started construction” means, the site work associated with, and directly related to the approved project is at a stage where rough grading is complete or utilities are installed. For rough grading to be considered complete, elevations are within 1 foot of final design elevations.

Drainage Complaints

The drainage complaints map and list are updated and maintained by the Stormwater Team. Use this information to provide documented drainage complaints for a permit application.

Drainage Complaints Map

Drainage Complaints List

**If you need to Report A Spill please use this form, or call the number listed on this page.

Surface Water Checklists, Guides, and Forms