Prospect Lake in Colorado Springs closed immediately due to positive E. coli test

COLORADO SPRINGS, Colo. (KRDO)-- The City of Colorado Springs has closed Prospect Lake in Memorial Park effective immediately to bodily contact, due to a positive test for elevated levels of E. coli bacteria.

The city learned of the test result Thursday, and by noon had posted signs around the lake's common swimming areas alerting users to the closure.

"I wish I would have known, and my daughter is not in there any more," said Krystal Gagnon, when told of the announcement. "My daughter isn't happy that she can't swim, and neither am I."

The test, which drew a water sample Wednesday, returned an E. coli level of 307.6 organisms per 100 milliliters. The acceptable level for E. coli is 255 organisms per 100 milliliters, according to the city.

Despite this test, the city said that the lake was retested Thursday; the results will be returned Friday and the lake could be reopened based on the new test results.

During the closure, the following activities are prohibited: swimming, bathing, paddle boarding, tubing, water skiing, and non-motorized boating of any kind. No pets are allowed. Fishing areas will remain open, though anglers are urged to clean fish well and remove guts.

According to the Colorado Department of Public Health and Environment (CDPHE), Elevated E. coli concentrations may result from fecal waste from swimmers, pets or wildlife, improperly disposed dirty diapers, excessive runoff from rain or flood, runoff from urban, suburban, or rural areas, or malfunctioning septic systems.

Erik Rodriguez, the city's environmental, health, safety and environmental specialist, said that droppings from ducks and geese are the likely cause of the increased bacteria level.

"It's been a while since we've seen this here," he said. ""We've seen additional waterfowl at Prospect Lake lately, so the increase in waterfowl can definitely add to the E.coli loading of the body of water."

However, the timing of the discovery was good for officials; it came just before a weekly application of an enzyme used to prevent a buildup of toxic blue-green algae that has affected the lake the past two summers, but not this summer so far.

"The enzyme is also good for keeping E. coli under control," Rodriguez said.

If the lake remains closed into the Labor Day weekend, it could affect the annual balloon festival at nearby Memorial Park -- where pilots traditionally skim off the lake's surface before lifting off.

"We're evaluating that, along with reopening the lake," Rodriguez said.

A group of women who have gathered to swim at the lake since the 1960s and 1970s, didn't let the closure stop them from swimming.

"We're careful in the water," said Chris Conboy. "We don't ingest the water or go in with cuts or sores that can get infected. We also spend time helping to keep the lake clean."

The city is still finalizing a design for an aeration system in the lake -- to help prevent high levels of algae and bacteria -- and boat owners are waiting to see if it will limit their use of the water.

"It's taken longer than I thought it would," said City Councilman Dave Donelson. "Parks and Recreation has told me that the vendor has had a hard time finding a compressor for the system, because of supply chain issues. I'm satisfied that we're making progress."

For additional information about E. coli, including symptoms of infection, visit CDC.gov/Ecoli.