After a busy weekend, the beaches at Presque Isle State Park were packed again on Monday, with people of all ages hitting the water to cool off.

Mary Krysiak and her family were visiting the park from Kittanning, PA. "The water is beautiful, it's like bath water," Mary said. "We're all playing in the water, it's super easy to get in, not cold, not shocking so it's a good time," she added.

Bob North, Lake Erie Lifeguard Manager said that Saturday when the temperature climbed into the 90's, it led to record setting attendance for the season.  "All of our records for this year were broken on Saturday, we had great attendance.  People were using the lake to cool off, exactly what it's there for."

Lake Erie water temperature though is at 79 degrees, warmer that usual this soon in the summer season.  Warm waters can promote bacteria growth, along with other factors such as winds, waves, and wildlife.

Already some beaches have been closed to swimming temporarily, because of high e coli counts.

The Regional Science Consortium uses predictive models based on extensive data for Presque Isle to help track bacteria trends in the water, and they use daily water sampling at multiple beach points around the peninsula to document exact counts, which they say always align with the models.  Executive DirectorJeanette Schnars, PhD said it helps that they have the ability analyze those samples in the lab at the Tom Ridge Environmental Center. "We are able to bring them straight back here, process them, and then get results out -- the very next morning after the incubation period -- to our managers along the waterfront and the beaches so they can properly advise the public whether it's safe to go swimming or not," Schnars said.

Lifeguard Manager Bob North said even on those occasions that they do have to close a beach because of elevated e coli levels, beach goers are very cooperative and there's always another beach open for swimming, or they can shift lifeguards and open a beach that wasn't staffed for the day.  "When possible we'll actually have a guard stationed at the entrance to the beaches that are closed and inform them of the beaches that are open...and I would say 99% of the people are thankful we're letting them know," North said.