By Larry Craig 

Walk almost any older Eugene neighborhood and you’ll see them: Sidewalk panels heaved up by tree roots, cracked and tilted slabs that catch a wheel or trip a foot; stretches of sidewalk so broken that people step into the street instead. 

Eugene needs to treat sidewalks as public infrastructure, not a private burden on individual property owners. The city is beginning to move in the right direction. But there’s a piece of the puzzle that deserves more attention: the trees themselves. 

Eugene’s beloved street trees, especially the mature trees that form a canopy in many of our historic neighborhoods, are often blamed for the very damage that puts them at risk of removal. “Root heave” is the technical term for tree roots lifting sidewalk panels. Root heave creates tripping hazards and accessibility failures that trigger complaints. 

The city investigates complaints and sometimes determines the only fix is to remove the tree when the roots lifting the sidewalk are too large to cut without risking the tree’s stability. The tree pays with its life for a problem we created by building concrete over its roots. 

Tree removal may not be the only choice. A University of Oregon master’s student named Alejandro Bechtle-Hanson has spent two years researching the tree-sidewalk conflict. Bechtle-Hanson is a landscape architecture graduate student with deep personal roots in the historic Whiteaker neighborhood. He once walked those same streets as a homeless teenager. His rigorous field study of 146 large street trees found that nearly 90 percent have lifted the pavement, making sidewalks inaccessible.

The findings challenge some common assumptions. It turns out that for mature trees, trunk size has almost no statistical relationship to how severely a tree lifts a sidewalk. Neither does the distance from visible roots to the pavement’s edge. What matters more is sidewalk age, tree species and the direction a tree faces relative to the sun. 

Bechtle-Hanson’s theory, which he plans to test through future research, is that root heave is a matter of time. Tree roots typically grow near the surface, where oxygen is available. Concrete attracts roots further by creating a moist environment through condensation. As the roots expand, they push up the soil beneath, naturally lifting the pavement above. 

The implications are sobering. If we keep repairing sidewalks the same way, we will keep losing trees. Every time we “fix” a sidewalk the conventional way, we may be slowly killing the tree that caused the heave. And those trees, some more than a century old, are a valuable resource. 

Saplings take decades to provide meaningful shade, cooling and stormwater management. In a warming climate, mature urban trees aren’t a luxury; they’re critical infrastructure. Without trees, our sidewalks and neighborhoods would be hotter, brighter, louder and more polluted. 

Bechtle-Hanson’s proposed solution is elegant in its simplicity: Replace concrete with boardwalks where trees and sidewalks conflict. Drawing on Eugene’s own history of wooden sidewalks and accessible forest boardwalks, the concept envisions a modular elevated system that bridges over root zones rather than crushing them. This allows water and air to reach the roots. 

Boardwalks can be repaired panel-by-panel without a concrete crew or up to a week of curing time. Repairing only the section also reduces the amount of material going to the landfill. Materials may include fiber reinforced polymer (a post-consumer waste plastic lumber), fiberglass, aluminum or possibly wood with careful application to avoid slippery surfaces. 

For Eugene, timing of Bechtle-Hanson’s research couldn’t be better. The city is actively rethinking its sidewalk repair system, exploring how to move from a complaint-driven, property-owner responsibility model toward something more equitable and proactive. That’s the right direction. 

But a truly forward-thinking sidewalk strategy also has to be a tree strategy, one that treats mature street trees as the irreplaceable public assets they are. We don’t have to choose between safe sidewalks and living trees. We just have to be willing to think differently about what a sidewalk can look like. But to fix our broken sidewalks, we need to talk about them. If you’ve ever caught your foot on a broken panel, watched a neighbor navigate around an impassable stretch or simply loved the shade of a bigleaf maple on a summer afternoon, your experience matters. 

Community United to Repair Broken Sidewalks (CURBS), a project of Better Eugene-Springfield Transportation, is still gathering community input through July 31. Please take a few minutes to fill out a survey about the sidewalks via the BEST website and share it with someone you know. 

Larry Craig is a retired 911 systems coordinator who rolls Eugene’s sidewalks in his manual wheelchair. He is a member of CURBS (Best-oregon.org/coc/walk) and the Wednesday Wheelers, a group of wheelchair users who meet to explore paths and trails throughout Eugene.