AURORA, Colo. The swim beach at Aurora Reservoir closed to the public on Wednesday due to elevated levels of bacteria in the water, which could potentially affect many peoples plans to recreate there during the Independence Day holiday.The elevated levels of bacteria found in the water were identified as E. Coli by City of Aurora spokeswoman Rory Franklin, who told Denver7 that because the reservoir is an untreated, natural body of water, its not unusual for levels of bacteria such E. Coli to fluctuate in the water from time to time.Like any untreated, natural body of water, levels of certain bacteria fluctuate. It cures itself naturally, but when the levels are elevated, its best not to swim, city officials said in a news release.For those still looking to create at Aurora Reservoir, not to worry: Kayaking, paddle boarding and the boating section of the reservoir is still open to the public.The city tested samples from Aurora Reservoir Wednesday morning and should have results by Thursday, at which point they may reopen the swim beach for the Fourth of July holiday, Franklin said.Though E. Coli belongs to a group of bacteria that usually lives in peoples guts without a problem, some strains can make people sick with diarrhea, urinary tract infections (UTIs), or vomiting. Children under the age of five, the immunocompromised and the elderly are particularly susceptible to severe illness, according to the USGS. Denver 7+ Colorado News Latest Headlines | July 3, 11am