Metro Nashville's urban tree canopy lost 674 acres between 2016 and 2021, according to the latest five-year assessment. This decline highlights challenges in maintaining green cover amid urban growth, even as overall canopy in Davidson County rose 1.6% over 11 years. The report maps existing trees, potential planting areas, and trends from 2010 to 2021 using 2021 aerial imagery, equipping arborists, residents, nonprofits, and officials with data to combat runoff, boost air quality, cool summers, support wildlife, and lift property values.
Key Trends and Losses Across the City
The assessment reveals uneven progress. While Davidson County's canopy grew modestly from 2010 to 2021, recent years show erosion. The T4 Urban transect suffered the steepest drop, losing 869 acres or 3.3% over the study period due to concentrated development (page 12). Nine of 14 community planning areas fall short of canopy goals (page 25), signaling risks to equitable green access.
Impervious surfaces cover 32% of the Urban Services District—40,814 acres—exacerbating stormwater issues. Over 32,000 acres of possible planting area (PPA) remain available there to counter this (page 11). In watersheds like Kerrigan and Driftwood, high impervious percentages demand action: their 790 acres of PPA could curb combined sewer overflows (page 19).
Street Trees as Stormwater and Health Allies
Street trees anchor Nashville's resilience. Canopies catch rainfall, cut runoff, and prevent flooding. Roots promote infiltration, reduce erosion, and filter pollutants, while transpiring water to ease soil saturation. Beyond water management, these trees foster mental and physical health, lower summer heat, and build climate defenses.
Each dollar spent on street trees yields $3 in returns, generating $9.85 million annually in benefits. This investment strengthens infrastructure and secures livable neighborhoods.
Path Forward for Policy and Planting
Every five years, Metro Nashville updates its UTC assessment to track these dynamics across geographic lines. Policymakers now hold precise data on canopy distribution and PPA to prioritize plantings, especially in vulnerable districts. Expanding street trees and tapping PPA promise to reverse losses, aligning urban expansion with environmental gains for a cooler, cleaner city.
