How will Evanston protect its shoreline amid climate change?

Evanston residents learned about the need for erosion protection along the lakeshore and weighed in how they want changes implemented at an open house Tuesday, Oct. 25, at the Evanston Public Library.

At the event, members of the Chicago-based SmithGroup engineering firm outlined the challenges climate change poses to public beaches and parks, and showcased different design options to protect and enhance them.

Some 50 people filtered through the open house over the course of about two hours. Those who attended voiced support for more natural-looking barriers and projects that will last longer and thus save money over the long term. But some attendees were worried the proposed solutions might not adequately address the hazards of climate change.

Lakefront facing erosion threats

One of the main threats to Evanston’s lakefront is changes in the level of Lake Michigan. Mark Wagstaff, a principal at SmithGroup, said climate change is leading to more variation in the water level of the lake.

Unlike sea levels, lake levels may not rise continuously as the Earth grows warmer. But Lake Michigan is expected to fluctuate more rapidly between periods of high and low water, meaning waterfront infrastructure needs to withstand a wider range of conditions. Deeper water can amplify the destructive power of the lake “exponentially,” Wagstaff said.

Another threat to the lakefront is changing ice patterns during the winter. Rick DiMaio, an Evanston resident and professor of meteorology at Lewis University and Loyola University Chicago, said that ice is “the key” to protecting beaches during the winter.

The protection from lake ice is likely to decrease as a warmer climate causes ice to form less frequently and later in the year, DiMaio said. 

In the winter of 2020 these two factors came to a head when record high lake levels and storms hit ice-free beaches, causing widespread erosion and damage to existing lakefront barriers.

The damage prompted the City of Evanston to initiate a series of repairs and highlighted the need for further upgrades.

In April, the City Council approved a $333,000 contract for SmithGroup “to design permanent shoreline stabilization solutions,” according to a staff memo. The city’s request for proposals called for the preliminary engineering and design work to be completed by the end of March 2023. Future phases of the project, involving additional engineering and actual construction, have yet to be funded.

The lakefront sites considered highest priority are the city’s water treatment plant, the dog beach, Greenwood Street beach, Dempster Street boat facilities, Elliot Park, Lee Street Beach, Clark Square Park and the Sheridan Road revetment.

Natural barriers favored

After learning about the challenges faced by the lakefront, attending residents viewed pictures of different barriers, and expressed their interest or opposition using green and yellow stickers. Residents clearly preferred natural options, peppering pictures of plant-based barriers with green stickers, and giving artificial options like a boardwalk the thumbs-down with yellow.

The city also has conducted an online survey asking residents to weigh in on their preferred solutions. Cher Wong, a landscape architect with SmithGroup, said her initial review of survey results confirms that residents generally prefer a natural shoreline.

Evanston residents Tom and Jane Wuellner, who were at the open house, said they support a more natural look on the waterfront. However, they acknowledged that different parts of the city’s shoreline may be best served by different options.

Some concerned about effectiveness

While many residents in attendance appeared optimistic about shoreline upgrades, others expressed doubt about how effective any options presented might be.

Evanston resident Pamela Ferdinand, a freelance journalist who specializes in science, was concerned that many of the options include hard barriers like stone seawalls, which she said can amplify erosion or redirect wave energy to other parts of the shoreline.

Ferdinand, a 2004 Knight Science Journalism Fellow, suggested the community may need to consider more adaptive steps, such as moving back the water treatment plant, or adding more permeable surfaces to the lakefront. “Lots of communities are moving vital infrastructure back from their oceanfronts and lakefronts,” Ferdinand said.

DiMaio said the community may need to adjust its expectations for what the shoreline may look like in the future. “The beach will exist some years and not others,” he said. “Putting more sand on the beaches every year is not the answer.”