Walkability and urban forests are part of climate resilience

Bright pink X’s appeared last week on more than a dozen trees lining Hartrey Avenue near Dempster Street, and by Monday morning chainsaws were at work. The project is part of the city’s Sidewalk Improvement Program, approved by the City Council two years ago to repair and fill gaps in the city’s network of sidewalks and make walking safer, especially around schools and healthcare and senior facilities.

The The Hartrey-Greenleaf Project is an early test of the sidewalk program and the city’s new tree ordinance, both of which reflect the priorities of Plan for climate action and resilience and that The Evanston Process for Local Needs Assessment.

The Tree Care Ordinancepassed by the City Council last fall, recognizes that trees are part of Evanston’s critical infrastructure — green infrastructure, as opposed to gray infrastructure like streets, sewers and sidewalks. Trees help with stormwater management by slowing and absorbing rain, while providing more immediate benefits to the people who live and walk near them, such as cooling shade and cleaner air.

The urban forest is connected, so the regulationwhich took effect June 1, “regulates the maintenance, protection, removal and replacement of existing public and private trees (my emphasis) within the City of Evanston, to protect and preserve the urban forest and all the benefits it provides to the community.”

The first priority is conservation, starting with trees that have grown to at least 6 inches in diameter. It is because it takes time for trees to provide benefits (including carbon sequestration) in excess of what is required to grow, transport, plant and establish them.

Threats to trees in urban areas are often associated with construction, so one of the ways residents may encounter the ordinance is when applying for building permits.

The city’s tree care officer, Angela Levernier, who joined the forestry staff in May, reviews permit applications involving trees and works with builders to find ways to protect and preserve healthy trees. If the preservation of a tree proves impossible, the ordinance requires that it be replaced according to a schedule reflecting the size and value of the tree. Oaks rank higher than trees with little or no wildlife value such as ginkgos, for example.

Satellite view of the west side of Evanston from Dempster to Greenleaf streets, showing the lack of tree cover. Credit: Google Earth

The Evanston Process Local Needs Assessment (EPLAN) completed in 2022 identified Evanston’s west side, where this part of Hartrey is located, as “most in need of additional investment in tree canopy cover, particularly given that this part of the city has higher concentrations of of vulnerable populations, who are disproportionately threatened by climate risks.”

But what happens when expanding the tree canopy meets another worthy goallike expanding the city’s network of sidewalks?

The Sidewalk Improvement Plan, like the Tree Ordinance, also promotes climate and equity goals, in this case by making it safer and easier for people to get around without relying on cars. This stretch of Hartrey running south from Dempster is a priority for new and improved sidewalks, in part because ETHS Day School located in the middle of the block, and Erie Family Health Center and Have dreamswhich provides services for people with autism, is located at the corner of Hartrey and Dempster. The project includes new sidewalks, replacement of old and deteriorated sections of the sidewalk, crosswalks and updated lighting.

Tree marked for removal across from Rebuilding Exchange and ETHS Day School. Credit: Wendy Pollock
Workers will begin moving trees on Monday. Credit: Wendy Pollock
Workers are removing the last of the large silver maple that shaded this part of the walk. Credit: Wendy Pollock
ETHS Day School was one reason this neighborhood is among the first to get a new sidewalk. Credit: Wendy Pollock

The Hartrey-Greenleaf project has presented significant challengesnot only because the street is narrow and heavily used, but also because it is, or was, lined with trees.

The city has a wide right-of-way in front of the houses along the west side, so it is within its legal right to build a sidewalk there and to remove trees in the way. The construction contract calls for 22 trees to be removed, 10 of them 15 inches in diameter at breast height or larger.

“Trees have been the biggest concern among residents,” said Terry Haynes, resident engineer at Singh & Associates, the firm overseeing the project for the city. “It’s a difficult situation. If we put in a sidewalk, lots of trees and bushes would have to come out; there’s not a lot of room.”

Rajeev Dahal, a senior project manager in the city’s Capital Planning and Engineering Office, confirmed in an Aug. 5 phone call that he had heard concerns from neighbors at two public meetings last year and had reviewed the trees with city arborist Kevin Ward, then the forest supervisor. They tried to save as many trees as possible, Dahal said.

Work began last week with inspectors laying the pavement “according to plan,” explained one of the surveyors. A number of trees in the path of the new pavement were marked for removal. The engineer can make changes, the surveyor said. That seems to be what happened.

Surveyor lays out new pavement according to plan. Credit: Wendy Pollock

After site visits by a city arborist, the sidewalk goes around some trees. Credit: Wendy Pollock

Haynes confirmed Monday that Emily Okallau of the city forestry department, which handled the ordinance last year, had visited Dahal late last week after the surveyors had finished their work, and some adjustments had been made before the bulldozer arrived to excavate the foundation for the new boardwalk.

In some places, the pavement is now lined with several old trees. Still, when the arborists started removing the big old tree that shaded her yard, a neighbor texted that she was “heartbroken.”

Trees will be replaced after the sidewalk is complete with mostly native species. The contract specifies 30 new trees, including oaks, tulip trees and basswoods, to replace the removed trees. It is not clear whether the city is following the replacement guidelines of the tree ordinance in its own sidewalk construction project.