Lake Overlay Regulations

WMTP Tree Protection Project

Whatcom County Lake Overlay District Tree Regulation Revisions

Updates to Improve Tree Retention on Private Parcels Within Our Local Lake Watersheds

WMTP worked behind the scenes for many months during 2022 with RE Sources and Whatcom County staff to develop much-needed revisions to Whatcom County’s Lake Overlay District (LOD) ordinances.

The LOD ordinances are special rules that private landowners must follow within Lake Whatcom, Lake Samish, and Lake Padden watersheds. Altogether, it’s an enormous amount of land area within our County. We focused on the LOD regulations that affected large, mature trees that are so essential to our watersheds and community.

Why These Rules Are So Important

Much of the forested area in our key watersheds sits on private lots. And most of the undeveloped private lots are covered in tree canopy.

Landowners would typically clear-cut log most or all of a site before building a home on a small portion of the lot. A classic example from Lake Whatcom watershed is shown below.

This common land clearing approach was easy to do and provided some extra dollars for the cut trees sold. But in the larger context of protecting our watersheds for our community, it’s unreasonable and unsustainable.

Retaining mature tree canopy on private lots will improve our community’s drinking water quality and climate resilience (to increasingly common torrential rains, heat domes, etc.). The retained trees also will continue to capture carbon and preserve habitat to slow the loss of biodiversity in the watersheds.

Our Revised Tree Canopy Rules

Under the prior LOD rules, up to 35% of a parcel’s tree canopy (3.5 acres on a 100% forested site) could be removed for ANY reason. Ouch!

Now the rules depend on whether the tree removal is due to development or for another reason…

If the tree removal is NOT related to development (such as to open a view or yard area, or to remove trees too close to a home), an owner may remove up to 20 percent of the tree canopy — but not more than 14,000 square feet — as measured from January 1, 2017 canopy levels on the property shown in aerial maps.

The 14,000 SF removal cap is key. In larger parcels, it retains MUCH more tree canopy, as you can see in the chart below.

For example, for a 10-acre parcel that’s 100% forested only up to .33 acre of tree canopy can now be removed from the site’s January 1, 2017 canopy levels. Under the prior LOD rules, up to 3.5 acres (35%) of trees could be removed. That saves over 3 acres of valuable tree canopy. This is a huge WIN for our watersheds!

What if the tree removal is related to development (such as building a home)? Our goal was to improve tree retention but still allow a reasonable amount of site area to be cleared to build a home or other structure.

The revised rules we came up with are progressive based on the size of the lot:

So now let’s compare the results. Under the prior LOD rules up to 35% of the tree canopy could be removed. For a 10-acre site, that means up to 3.5 acres. Now, under the new rules, the maximum removal when associated with development is 1.5 acre of tree canopy. That’s two acres of saved trees — another BIG WIN for our watersheds (while still allowing a reasonable site area to be cleared to build a home)!

Under the revised rules, other LOD ordinance provisions such as stiffer penalties for unauthorized tree removal have been established, too.

Watershed Trees Saved Over Time

Over several years, these significant tree retention rules for various size lots will likely save hundreds, possibly thousands, of trees in our local watersheds! The quantity per year will vary depending on the number of tree removal/construction permits submitted to and then approved by Whatcom County’s Planning & Development Services Department, and the size and nature of each lot affected.

Our revision recommendations received unanimous approval from the Planning Commission in early July 2022, and then unanimous approval from Whatcom County Council in September 2022. Now the new rules are in effect! Yay!

Volunteer Opportunities

• Interesting in helping us advocate for local watershed tree protection? Please contact us!

Related Links/Resources

Whatcom County’s Lake Overlay District Ordinance