Sandbags are being made and residents in several communities are being told to be prepared for rising water levels.
The Des Plaines River is sitting at about 7 feet in height, about double where it normally is at this time of year. It has about 6 1/2 feet to rise before it would breech a levy built in the last couple years to protect some Libertyville homeowners.
Elsewhere in Lake County, sandbags are being filled and the inventory of emergency flood equipment is ready north of Chicago.
As much as the Des Plaines River is causing worry, it is the Fox River from the Wisconsin line down to the Chain of Lakes area that is being watched most closely.
"Two inches of rain in a week is not typically enough to cause us problems," said Kent McKenzie, Emergency Management Coordinator for Lake County. "But when you put that, and it's over the entire river basin, there's enough volume of water in a short enough time that it causes issues."
Despite a mild winter and drought-filled 2012, recent rains have not dissipated deeply into the soil.
"We had several 6-10 inch snowfalls here in Lake County right at the end of the winter, and all of that water, of course, has melted," McKenzie said. "Some of it's been absorbed into the ground, so we're starting to see some replenishment and some relief from the drought we've had, but then over the past week we've had 2-3 inches of rain here in Lake County, and perhaps even more rain than that north of us in Wisconsin over the watersheds that drain into the rivers that run across Lake County."
Water management and transportation officials are expecting the Fox River to crest at 6 feet sometime between Saturday and Tuesday, likely causing flooding in the Village of Chain of Lakes as well Antioch, maybe Lake Villa and nearby towns.
Sandbags will be available for free through local officials -- and so will the advice that what's about to take place is fairly typical for spring in these parts.
"At a level of 6 feet, there's water across a few roads in low-lying areas around the lakes," said McKenzie.
The Illinois Department of Natural Resources is monitoring the water levels. They'll be opening and closing the dams in Algonquin and McHenry as required to mitigate the rain's effect.