Last year, Illinois notched a record no one wants to come close to repeating: 339 closings of Lake Michigan beaches due to high bacteria levels. 

As beaches open this weekend for the summer season, eight Illinois members of Congress signed a letter that fingers the city of Milwaukee as the culprit and asks the federal government to make the city clean up its act. "Milwaukee discharges a larger amount of waste into Lake Michigan than any other city," according to a letter sent Friday to Christine Todd Whitman, administrator of the U.S. Environmental Protection Agency. "The city has drained nearly 1 billion gallons of sanitary sewer overflow--industrial and other heavily populated waste--into the lake since 1995. Since the early 1990s, it is estimated that Milwaukee bypassed about 13 billion gallons of untreated waste water into Lake Michigan." 

In 1994, lake beaches in Illinois were closed just 10 times. Lake advocates acknowledge that stricter monitoring for bacteria has led to more closings since then but also say higher pollution levels are a factor. 

The lawmakers, all Democrats and led by Rep. Jan Schakowsky, said they want the EPA to "take immediate action to enforce the Clean Water Act and stop this dangerous trend." 

"It is unacceptable," the letter said, "that one city's harmful waste water disposal practices should be allowed to endanger the health of citizens throughout the region." 

But the executive director of the Milwaukee Metropolitan Sewerage District, Kevin Shafer, said it is not his city's fault when beaches in Chicago and elsewhere in Illinois are closed. 

"It's almost laughable our overflows are causing beach closings in Chicago," said Shafer, who blames storm water runoff contaminated with sea gull droppings. 

J. Val Klump, director of the University of Wisconsin-Milwaukee's Great Lakes Water Institute, sided with Shafer. 

"It's a real stretch," Klump said. "I don't believe it. There are just too many other sources of E. coli bacteria." 

Cameron Davis, executive director of the Lake Michigan Federation, a group that advocates lake conservation, said there is no direct proof of a link between Milwaukee's sewage overflow and Illinois beach closings. 

"But there's a lot of strong circumstantial evidence," he said, adding that the EPA "needs to take a look at Milwaukee's contribution" to the lake's pollution problems. 

In March, the federation sued the Milwaukee Metropolitan Sewerage District in federal District Court in Milwaukee. The suit seeks to stop the district from discharging sanitary sewage into the lake. 

"When Milwaukee coughs, Lake Michigan gets sick," Davis said. 

Milwaukee isn't the only city with a bad cough. "Overflows have occurred in Chicago," the lawmakers admit in their letter, but those overflows "usually flow away from city beaches." 

U.S. Reps. Rod Blagojevich, Bobby Rush, David Phelps, Jerry Costello, Lane Evans, Danny Davis and Jesse Jackson Jr. also signed the letter.