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A panel of three people discussed higher lake levels, disappearing beaches and sand erosion at a forum sponsored by the Illinois Sand Management Working Group and State Representative Robyn Gabel’s Office at the Evanston Ecology Center on July 10. The panel also discussed some short-and long-term solutions, including a pilot program with the Army Corp of Engineers to transport sand dredged from Waukegan harbor to three Evanston beaches.
The panel members were Cam Davis, Great Lakes point person for former President Obama, former president and CEO of the Alliance for the Great Lakes, and current employee of GEI Consultants; Lawrence Hemingway, Director of Parks, Recreation, and Community Services for the City of Evanston; and Alex Hoxsie, Planner/Architect, U.S. Army Corps of Engineers.
Fluctuating Lake Levels
Rep. Gabel kicked off the discussion, saying, “Illinois’ shoreline is dynamic. It changes all the time. Three years ago we were told the lake was at the lowest point it had ever been, and it was only going to get lower and lower because of the evaporation. And that has proved not true. It proves how dynamic it is.”
“Our lake levels are really, really high,” said Mr. Davis. “The Army Corps of Engineers has determined that three of the Great Lakes – Lake Superior, Lake Erie and Lake Ontario – have reached record levels, and Lake Michigan is one inch away from its record high.
“We just had the wettest May in our region, and intense rainstorms are contributing to high lake levels, and the vortexes contribute as well.”
But he said the issue is complex, and “if you ask experts to tell you definitely why this is happening, a lot them don’t even know.”
“Lake levels go up and down. They fluctuate. In fact, it’s a very healthy thing for lake levels to go up and down,” Mr. Davis added. “I try to avoid talking about high or low lake levels as being good or bad. The fact is they can have all different ramifications.”
When asked if climate change was a factor in causing the record and near record highs in the lake levels, Mr. Davis said he thought it was having an impact on the fluctuation of lake levels. “If they are exacerbated so that lake levels are whipping up faster than they usually have or lower than they usually have, that makes it tough on society. We have to figure out how to adjust to that faster pace of fluctuation.”
Mr. Davis said, though, “There are approaches we can take to help our shoreline that can combine hard traditional approaches with softer approaches. … Trying to manage our coastline really involves staggered, sequential approaches, using short- and long-term measures.”
“We can use templates to some extent, but every shoreline is different. We can’t use a cookie-cutter approach.”
Some examples of hard approaches to prevent coastline erosion include building a concrete sea wall or placing large boulders along the shoreline. Large boulders have been placed at many spots along Evanston’s shoreline.
Softer approaches may include using plantings that can hold the soil or sand in place.
Mr. Davis said an analysis should be taken of the harder structures to determine their expected lives and when they may need to be replaced and some other alternatives may need to be used.
The Pilot – Transporting Sand
Mr. Hemingway said the City was participating in a pilot program that was authorized under the federal Water Resources Development Act. Only 10 projects in the nation were selected, he said, and the one in which Evanston is participating is the only one on the Great Lakes.
Under the pilot program, sand that the Army Corps of Engineers dredges from Waukegan Harbor will be transported to Evanston and placed on Greenwood Beach, Lee Street Beach and the Dog Beach.
Mr. Hemingway said:
• A depth of about 2 1/2 to 3 feet of sand has eroded at the Greenwood Beach in some spots, and the surface area of the beach is significantly less than it was several years ago.
• At Lee Street beach, a lot of the beach surface area has been lost due to the high water levels, and sand has eroded all the way up to the high water mark.
• The Dog Beach is completely underwater, and sand at the entrance to the beach has eroded so that the sand is now 12 inches lower than it had been several years ago.
The pilot program “will protect our beaches from shoreline loss caused by high water levels using dredged material from the Waukegan Harbor,” said Mr. Hemingway. “This is a cost-effective way to try to acquire some sand to try to stabilize beaches that have lost so much surface area.”
Mr. Hoxsie said three other municipalities are also participating in the pilot: Glencoe, Lake Bluff and North Chicago.
He said the basic premise of the pilot is: “It’s taking material that is a problem somewhere, moving it, and solving a problem somewhere.”
Mr. Hoxsie said Waukegan Harbor has an inner harbor, an outer harbor and an approach channel. He said sand in Lake Michigan is naturally moving from the north to the south, and that sand tends to settle and build up at the mouth of the harbor.
The Army Corp of Engineers has been dredging the sand from the approach channel to keep the harbor open and safe for navigation, and it has typically placed the sand in the lake approximately one mile south of the harbor where it can get back into the process of moving south. Typically the Army Corps dredges about 70,000 cubic yards in a year, he said.
Under the pilot, the Army Corps of Engineers will transport the sand dredged from Waukegan Harbor in a given year to the three beaches in Evanston and to beaches at the three other municipalities. The cost of transporting and placing the sand will be paid 100% by the federal government, Mr. Hoxsie said.
During placement of the sand on Evanston’s beaches, a vessel would be anchored off shore and a pipeline would run from the vessel to the shore to carry the sand to the beach in a process called hydraulic offloading.
Mr. Hoxsie said, “The sand is generally free of debris and is considered a high-quality material and it’s not contaminated. Our records substantially show no detectable PCBs or asbestos.”
This is an issue because it was discovered in the 1980s that a local industry had discharged oil containing PCBs in the Waukegan Inner Harbor. The Inner Harbor sediment was found to be contaminated with high levels of PCBs and was declared a Superfund Site. The Army Corps of Engineers says the site has been cleaned up on several occasions and, as of 2013, only trace concentrations of PCBs were found. One speaker said they found .06 parts per million.
The Army Corps of Engineers says the PCB contamination never extended to the Approach Channel and only trace amounts were measured in the Outer Harbor. The Army Corps of Engineers says the Outer Harbor was dredged in 2014, and no PCBs were detected there.
Another possible issue is that a plant that manufactured asbestos-containing materials was located near the Waukegan Harbor. The Army Corps of Engineers says a study conducted by the Illinois Attorney General’s Office concluded that the sand in the Waukegan Approach Channel was not contaminated.
People at the forum, though, raised concerns about PCPs, asbestos, the New Zeland Mud Snail and other contaminants that could come with the sand. Mr. Hoxsie said people should submit comments to the Army Corps of Engineers, and they would be analyzed by the biologists.
“We’ll have a better understanding of how we can utilize the potential sand as the project develops,” Mr. Hemingway said. “One of my concerns is we can put the sand out there today. Depending on mother nature, it could be gone tomorrow.”
Mr. Hemingway said, “We are going to walk our entire shoreline in the next 30 days. We have to really get a true understanding of the entire shoreline in Evanston.”
He said the City’s engineers would participate in this process and they would put together a plan and then sit down with the Army Corps of Engineers to talk about long- and short-term solutions, and also how to address emergency situations.
Jetties and Artificial Reefs
The panel and people attending the forum also discussed jetties and artificial reefs and the role they might play in either protecting or adversely impacting the shoreline.
Mr. Davis said there are many jetties or structures that extend out into the lake, including along Evanston’s shoreline. Because the natural flow of sand in the lake moves from the north to the south, he said, these structures gather sand on the north side of their walls, and then sand erodes on the south side.
He said many of the jetties that were built into the lake off of Evanston’s shoreline were built a long time ago. “That’s something we know we have to look at.”
When asked if removing the jetties would help stop erosion of the sand, Mr. Davis said, “I think it would only be helpful if it were done uniformly around the lake. “Part of the problem is the cascading effect where you have one and then another and another. You start to see the accretion on the up drift side and the erosion at the down drift side. I don’t know that you could pull one off and solve the problem. I do think we’ve manipulated the shoreline so much at this point that it would be tough to just remove them and not see a lot of damage happen.”
Several people asked about building artificial reefs offshore to protect the lakeshore. Mr. Davis said there have been efforts to build artificial reefs in Lake Michigan, but added, “Our experience at GEI has been unless they are anchored very well, the wave energy underneath the shore line can cause a lot of damage to them. That said, I think it’s one of those approaches we need to keep working on.”
Diane Tecic, Coastal Management Program Manager at the Illinois Department of Natural Resources, said reefs can be a good long-term strategy, but it was important to find the right way to construct them so they not only reduce some of the wave strength and possibly change some of the currents to protect the shore from erosion, but also help to improve the aquatic habitat.