Stagecoach After closing its beach Wednesday because of a high E. coli count in the water, Stagecoach State Park officials re-opened the public swimming area Friday morning after water tests showed the reservoir was clean.
Stagecoach State Park Manager Fred Bohlmann said the high count of E. coli, or Escherichia coli, came from water tests park officials took at the beach on Monday. The results came back on Wednesday showing the south part of the beach with a high count, at 370 colonies per 100 milliliters of water. The permissible limit set by the Colorado Department of Public Health and Environment is 235 colonies per 100 milliliters.
"If you go over that," Bohlmann said, "you've got to close down."
A north beach test, which was taken 50 feet away at the same time, read 20 colonies per 100 milliliters. Therefore, officials determined that the high count was "extremely localized," Bohlmann said.
After closing the beach on Wednesday, park officials took another water sample in the south part of the beach. On Friday the results came back showing the south end of the beach under permissible levels at 24 colonies per 100 milliliters of water.
Routt County Public Health Nurse Patsy Ford said there was a day-care group swimming at the beach during the time of the high E. coli count, but no symptoms of the bacterial infection nausea, vomiting and diarrhea have been reported.
"This was a very odd situation for Stagecoach," Colorado State Parks Spokesman Steven Hall said.
Since 1998, 60 water samples have been taken in the reservoir, with the highest count being 22 colonies per 100 milliliters. Plus, 50 of those samples showed zero colonies, he said.
E. coli is passed through animal or human feces and causes illness and sometimes death. Bohlmann said there could be a variety of reasons why the water test showed a high E. coli count on the south side of the beach, but run-off after rain is sizing up to be the most logical.
Nadine Harrach, from the Routt County Environmental Health Department, said there are large grazing fields above Stagecoach Reservoir. When it rains, the manure can be picked up in the run-off and go into the Yampa River, which runs directly into Stagecoach Reservoir.
"The state requires that they do testing in the reservoir. If that day falls on a day after a rain storm, you are going to get a high count," she said.
Stagecoach officials test the water five times a month at the beach, Bohlmann said.
Ford said swimming in lakes, rivers and reservoirs after a rain storm isn't a dangerous situation. However, E. coli risks will be higher.
The E. coli that the water test showed is actually an indicator bacteria, which means it is not necessarily the E. coli strand 0157 that is responsible for causing illness, she said.
Bohlmann said since the second test showed levels were back to normal, the state didn't test for the 0157 strand.
Also, a state standard of 235 colonies per 100 milliliters is conservative, Ford said.
"It doesn't mean you will get some disease" if the water test is over that mark, Ford said.
Bohlmann added that ducks and pelicans also could have congregated at the beach before the testing, or a child with a dirty diaper could have been in the area right before the testing, which could have resulted in the high mark.
Bohlmann said if the problem was more serious, like a septic system leaking into the reservoir, it would be an ongoing issue.