Town amends tree rules

Building a home in Coupeville will no longer require an excessive amount of trees into the backyard.

Building a home in Coupeville will no longer require cramming an excessive amount of trees into the backyard.

After years of concerns and complaints from community members, the Coupeville Town Council unanimously approved amendments to the tree canopy ordinance included in the town’s code.

Now, instead of requiring individual trees to be planted, the town will regulate tree canopy coverage.

Associate Planner Joshua Engelbrecht said the ordinance hasn’t been updated for more than a decade, despite numerous complaints from community members who were trying to build a home in Coupeville.

“The existing tree density methodology was basically a division problem,” he said during a council meeting Tuesday.

Engelbrecht explained that the previous formula has consisted of subtracting 1,500 square feet from the current lot size. The result is then divided by 200, and the final result is the number of tree credits the homeowner needs to meet in order to be in compliance.

Basically, as exemplified during the meeting, a 15,000-square-foot lot would need 67.5 credits, therefore about 34 large trees must be planted on the property. But a property with a house, a driveway and other elements could hardly fit so many trees, which wouldn’t have enough space to grow in a healthy manner and would pose a safety risk to the homeowners.

In the new formula, the areas unfit for trees — like a driveway, a building or a pool — would be subtracted from the total lot size. Then, depending on the size of the remaining plantable area, the town establishes what minimum percentage should be covered by tree canopy, which is then multiplied by the size of the plantable area. The number of trees to be planted will also depend on the type and size of the tree.

Engelbrecht provided council members with an example to better illustrate the formula.

A 15,000-square-foot parcel has 8,854 square feet of tree incompatible area. The plantable area resulting from the subtraction is 6,146. The plantable area is then multiplied by the minimum area to be planted, in this case 0.3 (30%), resulting in a minimum of 1,843 square feet that need to be covered. Therefore, the owner should plant four to nine trees, depending on the species, which must provide sufficient coverage by their 20th year of maturity.

When possible, the majority of trees planted or retained should be native species.

Engelbrecht said town staff used feedback from the community and incorporated practices from nearby jurisdictions, like Snohomish County. According to information provided in the packet, the International Society of Arboriculture Guidelines for Developing and Evaluating Tree Ordinances also recommends jurisdictions to regulate tree canopy coverage rather than individual trees.

A complete list of changes and rules can be found by visiting and selecting the March 12 “packet.”

The amended ordinance includes new or modified definitions and clarifies some uncertainty around who needs a clearing permit. For example, removal of trees from a developed property is exempt from a clearing permit but needs a certificate of appropriateness. Pruning and maintenance activities are also exempt. On developed commercial parcels “it is likely that the site will feature an associated landscaping plan, for which continued compliance would be ongoing.”

Furthermore, the amended rules establish that parking areas with ten or more parking stalls should provide shade trees in landscaped areas and along pedestrian pathways. The parking areas should provide a tree canopy coverage of 50% over all paved areas within 15 years of planting.

The use of fees in lieu of planting trees is more restricted as it can only be used due to the presence of critical areas on the site or on-site constraints that don’t allow owners to meet the minimum percent coverage.

Engelbrecht said the ordinance will need more tweaking in the future.

“Hopefully it addresses the concerns and makes it a little bit more streamlined and straightforward for folks who are trying to build their houses in Coupeville,” he said.