As the latest salvo in a man-versus-nature battle, the Lake Forest City Council has approved a $58,400 expenditure to protect its milelong lakefront beach and scenic bluffs from the ravages of waves and storms.
It’s just one piece of a massive, if relatively little-known, shoreline problem on the North Shore that may be nearing a solution.
“The beach is an important asset to the city,” said Ken Magnus, Lake Forest’s city engineer. “We fear the high lake levels. The probability of erosion problems exist if we don’t do something.”
Although Chicago’s crumbling concrete Lake Michigan shoreline has captured public attention for years, Lake Forest’s problems demonstrate anew that the North Shore’s swanky lakefront also is battered by the same forces of nature, however different the problem and the potential strategy for solving it.
After decades of debate over who pays for what, 20 miles of Chicago’s shores–anchored by now-crumbling concrete revetments– are being rebuilt for $272 million.
And now coming to the northern suburbs’ rescue, the Army Corps of Engineers says it is only $200,000 away from finishing a study that could lead to paving 22 miles of shoreline from Waukegan to Wilmette with cobblestones by 2000.
The layer of stones on the lake bottom just offshore may stop the severe scouring that is digging into the lake bottom and causing waves to become more violent. Moreover, such a stone layer possibly could become sand-covered once it halts erosion.
A panel of erosion experts meeting last August in Chicago concluded that the paving scheme “is the only thing that will work,” said Philip Bernstein, planning chief of the corps’ Chicago district.
The cost: A mere $24 million for what is considered a permanent solution to raging erosion that costs millions in damage each year along the North Shore and threatens $350 million worth of structures.
“A plan like this would be very cost-effective and dramatically minimize repairs in the future,” Bernstein said. “It may serve as a model of how problems like this could be addressed elsewhere on the Great Lakes.”
Taking a cue from nature, Bernstein proposes dumping a 12- to 15-inch layer of rocks off the North Shore shoreline, in 6 to 20 feet of water. The rocks, 3 to 11 inches in diameter, would extend between 300 and 500 feet into the lake in places. Experts call this armoring the lake bottom.
Since the stones would be in deep offshore waters, they would not be visible from shore or interfere with beach activities.
Bernstein said he is searching for $200,000 more to conduct wave studies on how cobblestones react in storms and would like to finish a study within a year so it can be sent to Congress for approval and funding.
Bernstein expects a lot of public pressure for such a move, in part because of federal responsibility for erosion along the North Shore.
“Everyone who lives on the shoreline is experiencing ongoing problems which require massive new investments to protect the shoreline and infrastructure along the shore,” he said.
Bernstein estimates that about $350 million worth of structures such as water-treatment and power-generating plants are at risk along the shoreline, not to mention millions of dollars’ worth of private property owned by some of the most wealthy and powerful people in the nation.
On the North Shore, he explained, erosion of the natural beaches and lakefront bluffs began around 1885 with construction of Waukegan harbor, which was built and is maintained by the Army Engineers.
The harbor interrupts the southerly flow of sand that once replenished beaches as they were washed out by waves. Sand beaches “trip” waves, scattering their destructive force.
“The (natural sand-transporting) system was irretrievably damaged between Waukegan and Wilmette,” Bernstein said.
Today, the sandy lake bottom that once protected the shoreline from wave damage is gone.
Instead, the lake has been blasting away at the hard clay bottom that lay underneath. Waves have gouged five or six feet out of its clay floor so that now deep water lies just offshore.
This phenomenon was discovered only a few years ago.
“The deeper the water, the more severe the waves,” Bernstein said.
These waves thunder against seawalls, groins and piers intended to protect beaches and lakefront property.
Bernstein noted that some structures already have been replaced five or six times since the turn of the century.
In Lake Forest, the City Council voted Monday night to pay Lake County Grading up to $26,400 for emergency sand moving to protect the beach east of Lake Road and south of Westminster Avenue. The council also voted to pay McClure Engineering Associates Inc. up to $32,000 for an engineering design to restore 150 feet of unstable bluff at the beach’s south end.
The Illinois Department of Natural Resources has already agreed to provide $200,000 toward the bluff rehabilitation, which is expected to cost about $715,000, city officials said.
The Lake Forest project was instigated after storm damage this fall and should keep parts of the milelong beach from being washed out this winter and protect walkways and parking areas, city officials said.
