Tree Removal in Mercer Island
What you need to know in Mercer Island
For most private‑property tree removals or major tree work, a permit is required under the city code. The city’s “Tree Permits” program covers private‑property removals, development‑related removals, and removal in critical areas.
Mercer Island, Washington
If a tree is on a public right‑of‑way (street, sidewalk strip, or other City‑owned easement/property), any pruning or removal requires a permit from the city’s urban‑forestry / public‑works department.
Mercer Island, Washington
For trees in “critical areas” — e.g. wetlands, watercourses, landslide hazard zones, or buffer zones — removal is tightly restricted. A permit will only be considered if certain criteria are met (hazardous tree, diseased/declining, or ecological/slope‑stability benefit), and the permit application must include a restoration or mitigation plan prepared by a qualified professional.
Mercer Island, Washington
If tree removal is associated with development or construction on the property, a full tree‑permit application is required. In many cases, the property owner must preserve at least a certain percentage of “Large Trees” over a 5‑year rolling period.
Mercer Island, Washington
When a Permit May Not Be Required
Permits may not be required when:
You’re doing normal tree maintenance or pruning, limited to no more than 25% of the tree’s total leaf area — as long as it does not involve a critical area or right‑of‑way.
Mercer Island, Washington
You’re cutting a “small tree”, defined as under 10‑inch diameter (measured 4.5 ft above grade), and the tree is not designated “exceptional” and is not located within a critical area or buffer.
Mercer Island, Washington
Removal is due to a genuine emergency or hazard (threat to life or property) — but even then, you must notify the city, and apply for the permit within 14 days after removal, with documentation (ideally an arborist report, or at minimum photos) of the hazard.
Mercer Island, Washington
What Canopy Solutions, LLC Can Do For You on Mercer Island
At Canopy Solutions, LLC, we offer:
Permit review & determination — We'll review your parcel (zoning, critical‑area overlays, past development history, etc.) to determine whether a permit is required.
Full permit application prep & submittal — We can prepare and submit applications for tree‑removal, whether on private property, in sensitive zones, or associated with development.
Arborist coordination & documentation — When required (e.g. critical‑area removals, hazard trees, or larger trees), we coordinate with qualified arborists to supply health assessments, hazard evaluations, and mitigation / restoration plans.
Mitigation & re‑planting planning — When trees are removed, we help design and implement replacement planting or ecological restoration plans as dictated by the city code.
Compliance & timing guidance — We advise on when removal triggers special code requirements (e.g. tree density retention, buffer zones, public‑right‑of‑way) to avoid surprises, penalties, or delays.
Important Notes for Mercer Island Clients
Even modest‑sized trees (10″+ diameter) removed from residential parcels generally require a permit unless they fall under the “small‑tree” exception.
Critical areas — streams, wetlands, steep slopes, watercourses — add extra layers of regulation: if a tree lies in or near those zones, expect stricter scrutiny and likely re‑planting or mitigation obligations.
Hazard removals must be documented carefully — photos or arborist reports — and a permit application submitted within 14 days.
Removals in the public right‑of‑way require a separate permit; don’t assume “front yard = private land.”


