Fox Lake resident Bruce Burger laughed loudly with friends as they stacked sandbags around his York Street home Thursday afternoon.
After nearly a full day of downpours, murky lake water was slowly creeping through his backyard, threatening to work its way into his garage.
But Burger didn't seem upset.
"What can you do?" he said. "This ain't the first time, and it definitely won't be the last."
The rain finally stopped falling over Lake County -- but the flood damage it will cause here is expected to worsen today and into next week, officials said.
The county's two largest rivers -- the Fox and the Des Plaines -- feed into Illinois from Wisconsin, and rain there and here has swollen the waters above flood levels. As water flows south into Lake County, the rivers will continue to rise.
According to the National Weather Service, the Fox River in New Munster is expected to crest at noon Saturday at some 5 feet over flood level. That water will arrive in the Chain O' Lakes on Monday or Tuesday, officials said.
To the east, the Des Plaines River was 3½ feet above its flood stage Thursday. Communities along the river could see record water levels, said C. Kent McKenzie, coordinator of the Lake County Emergency Management Agency.
According to the National Weather Service, the Des Plaines in Lincolnshire was expected to crest at 7 a.m. this morning. The level was expected to decrease slightly by this afternoon but not drop below flood stage until next week.
Lake County Board Chairman Aaron Lawlor declared an emergency in the region, an important first step for getting disaster relief funding.
"This is a very serious situation," McKenzie said during a news conference Thursday.
Significant rain overnight changed official predictions for the worse. At times, more than an inch of rain fell in 20 minutes, McKenzie said.
"We were quite surprised at the volume of water we saw at rain gauges this morning," he said.
McKenzie predicted the impending flood could exceed those that struck the area in 2007 and 2008, disasters that affected hundreds of homes and businesses.
"This will have an impact on the local economies," he said.
An estimated 400 homes in and around Fox Lake are in danger of flooding because of proximity to the Chain, said Annette Wolf, director of the village's Emergency Services Disaster Agency.
About 100 homes in the Knollwood Park, Kings Island and Eagle Point subdivisions had been damaged by floodwaters by Thursday afternoon, Wolf said. Homes at the end of Atwater Parkway and Lakeside Lane were surrounded by water, too.
"It's bad out there already," Wolf said.
"All we can do at this point is get sandbags out there for people who need them."
Authorities don't know how high the water in the Chain will rise. The U.S. Geological Survey shows Nippersink Lake in Fox Lake was already about 1 foot over flood stage Thursday.
Halfway across the county in Lincolnshire, the Des Plaines River overflowed a protective berm in some areas and broke through a levee. The river rose rapidly overnight because of local heavy rain, and it was expected to rise to major flood stage levels by Thursday evening, officials said.
Flooded areas are "going to take a long time to drain down," said Kurt Woolford, flood operations manager for the Lake County Stormwater Management Commission.
The town's Londonderry Lane and Lincolnshire Drive were shut down because of flooding. More closures could follow, officials said.
Firefighters used boats and rafts to rescue some residents from flooded homes. Among them were 72-year-old Arlene Marshack and her husband, Martin.
Half a foot of water had rushed into their home. They got out with their two cats.
"I'm very sad," Arlene Marshack said. "I loved this place and I don't think we will ever come back to it."
In Gurnee, water was pushing east from the Des Plaines River into what's known as the village center.
Police closed Route 132 in the area, sending eastbound traffic down O'Plaine Road to Washington Street.
With so many roads expected to close, the most up-to-date travel information from the Lake County Division of Transportation can be found online at lakecountypassage.com.
Gurnee resident Mark Horvat was among the volunteers filling sandbags outside Viking Middle School on Old Grand Avenue.
Horvat said he took the day off from work to help his community.
"My basement is doing good, but you call around to friends and family and neighbors to make sure they're doing OK and such," he said while breaking briefly from his duties. "Coming out (to help) wherever you can."
Major attractions including Six Flags Great America, Gurnee Mills and Key Lime Cove are expected to be safe.
Damage wasn't limited to properties near the two rivers.
A subbasement at Libertyville High School flooded early Thursday, prompting officials to cancel classes and on-campus activities for the day and on Friday.
Fire Chief Rich Carani said the flooding occurred after an underground pipe burst. There was no fire.
Flooding wasn't limited to the building. Behind the school, Butler Lake overflowed its banks and covered a large portion of the north parking lot.
"I've never seen it come out this far into the parking lot in the years I've been here," District 128 spokeswoman Mary Todoric said.
With no reading, writing or arithmetic to study, about 70 students helped fill, deliver and place sandbags in local neighborhoods, Libertyville Township Supervisor Kathleen O'Connor said.
"I think it's been nice for the residents to see all these kids they don't even know helping out," she said.
• Daily Herald staff writers Gilbert R. Boucher II, Lee Filas, Bob Susnjara and Mick Zawislak contributed to this report.