Canopy cover drops hundreds of acres in Tumwater

Tumwater's canopy cover decreased by 560 acres between 2020 and 2025, representing a drop from 49% to 38% of its total land. The most significant losses occurred in single-family residential areas, which saw a 6 percentage point decline to 46%, translating to the loss of 377 acres. General commercial zones also faced declines, losing 87 acres and falling to 33%. The Urban Forest Management Plan sets a citywide canopy goal of 39%, which Tumwater is close to achieving. To produce the assessment, the city utilized machine learning to analyze aerial imagery, achieving a 97% accuracy in identifying tree cover.

The city plans to conduct these assessments every five years to measure the impact of regulations on urban forests. Five zoning types have already met their assigned canopy goals, indicating some progress in specific areas. An online dashboard will showcase this data as part of the city’s Green Team 2024 report.