Stream Buffers
On March 16, 2026, Kenmore City Council will continue to discuss updating the stream buffers within the city. This update has the potential to impact nearly 20% of parcels in Kenmore. The initial impact will be roughly one in five property owners, but because the buffers will impact areas that are most sensible to locate future higher-density development, the long-term impacts ripple much further into the community.
Why is this happening?
The City is required to update their critical areas ordinance (CAO) periodically to conform with “best available science” (BAS). The guidance that is being used is from Washington Department of Fish and Wildlife (WDFW) as the source for BAS, and to update the riparian (stream) ecosystems as critical areas.
What is changing?
Kenmore is considering three options: low, medium and high. These new buffer proposals all impact substantially more parcels than our current stream buffers. Although all options are based on BAS, the high option is WDFW’s preference. This is based on “site potential tree height” – or the height a tree could potentially grow to at 200 years of age. Because each option is based on BAS, the low option is sufficient for the protection of the riparian areas. The consultant that Kenmore hired, Facet, concluded that the “low” option meets WDFW’s standards and closely aligns with the averages of site-potential tree height (STPH).
WDFW has an interactive map where you can find your parcel and see the site potential tree height: WDFW Riparian Ecosystems Maps and Assistance (once you click on the parcel info, push the right arrow in the window that opens). Clicking on a few parcels, you’ll see there’s a large variation in the potential tree height.
Maps are linked at the bottom of this page: Stream Riparian Management Zone and Stream Buffers | City of Kenmore Washington
What if my home is impacted?
If your home is impacted by the new buffer, it becomes “non-conforming.” This term is often misused but means that the structure or use was legal under previous zoning, but because the zoning has changed, the structure or use would not be allowed today. It is no longer “conforming” to the existing zoning code.
When you are “non-conforming” you can continue your current use uninterrupted, but typically you cannot expand your non-conforming usage. For example, if you own a large lot with a single-family home and would like to build an accessory dwelling unit on the property for extended-family living, you would not be able to do that. There would also be strict limitations on any expansion to the existing structure.
If you have vacant land in an impacted zone, the most recent discussion with City Council indicated that you would be entitled to a “reasonable use exemption” and would be able to build one single-family home. The value of any impacted parcel, whether vacant or improved, will go down due to the non-conforming use restrictions and complications involved in developing it.
You can see if your parcel or structure is impacted here: 638990680771500000
Kenmore’s code on non-conformance: Chapter 18.100 GENERAL PROVISIONS – NONCONFORMANCE, EXISTING LEGAL USES, AND TEMPORARY USES
How have other cities handled this?
Cities have chosen different options - Renton chose to keep their existing buffers and add a performance requirement, which includes adding native planting and being fenced off. Mountlake Terrace chose the low option. Both of these were based on the fact that they are already developed, urbanized areas, where the need for housing and infrastructure (existing and future) must be balanced with preservation. As they are an increase, either in width or enhancement, over previous buffers they both provide an improved outcome for the habitat while balancing the needs of a growing city.
Impact Beyond Individual Parcels
Kenmore has housing and growth targets we have to meet – this includes market rate, affordable, and STEP housing. Where our land capacity analysis shows sufficient capacity, removing roughly 20% of our parcels as stream buffers changes both how much we can grow and where we can do it. Many of the parcels impacted by the increased setbacks are already our most dense housing - manufactured home communities, condos, apartments and townhomes. The buffers also hit our arterials (Juanita, 61st, 80th, 78th) which is generally the first choice for upzoning when it comes to accommodating future housing needs. With these off the table, new housing would need to be accommodated further in the neighborhoods.
We also want to remember that much of our city budget comes from real estate tax - when we freeze our current uses as non-conforming, we limit our ability to expand our tax base and allow more people to contribute to paying for our city functions. The slice of the pie that we’re each responsible for paying stays the same, while the cost of the pie grows.
Engagement Opportunities
Council will be discussing this again on March 16th. Anyone with an impacted parcel SHOULD have received a postcard.
More info from the city is below:
