Calls from parents and a desire to keep the Harford water supply from contamination led County Executive James M. Harkins to order the water systems of Joppatowne High and Magnolia Middle schools shut off Thursday afternoon, causing school officials to close the schools yesterday.
Students attended classes Wednesday and Thursday at the two schools after the water had been "superheated" Tuesday to kill the Legionella pneumophila bacteria in it.
But when a letter was sent home Wednesday afternoon notifying parents of the contamination, they began calling Harkins' office and asked the principal at Joppatowne High during a Thursday night meeting to explain in greater detail what was wrong.
"At Back-to-School Night parents were questioning the principal about it. By the end of the night, they made the decision to close," said Barbara Metzbower, treasurer of the Joppatowne PTA.
A spokeswoman for Harkins said yesterday that he ordered the water shut off because the school has no back-flow prevention system that would stop potentially contaminated water from re-entering the county's water supply.
"If there's any remote possibility, the county executive will err on the side of safety, and he truly believes that this is remote," said Merrie Street of the county executive's office.
Harkins did not learn of the Legionella readings until Thursday afternoon, however. "Harkins felt it would have been better if we had been on the front end of things," Street said.
School officials learned of the results of the Aug. 8 test showing high Legionella levels Monday afternoon.
But lacking any official protocol in this situation, they called the Harford County Health Department, according to Don Morrison, spokesman for the schools.
The Health Department instructed the school system to administer a superheating treatment, which was conducted Tuesday.
"That would have been the end of that story, except that there was some conjecture in the community that there was Legionnaires' disease," said Morrison.
The continued attention to the water supply has largely been to ease the concern in the community rather than to deal with a valid health threat, he said.
Both schools will reopen Tuesday morning, if results from samples taken during the weekend are at acceptable levels for bacteria.
Legionella is a common bacterium that, in rare cases, can cause Legionnaires' disease. Symptoms of Legionnaires' disease include fever, chills and a cough and can lead to pneumonia.
The disease typically afflicts men over 50, smokers, diabetics and people suffering from chronic lung disease or kidney disease.
The two schools underwent a "super-chlorination" process yesterday to reduce levels of the bacteria in their water systems.
Samples were taken last night to determine if the treatment was successful.
Morrison is confident that the results from last night's samples will indicate that the schools are completely safe.
The county is expediting the test in hopes that normal results will be available before school on Tuesday.
Schools are not required to test for Legionella, but this is the fourth year Harford County has tested its nine high schools and some middle schools, according to Morrison.
"The only reason we're testing this is because the public has so much concern in recent years," about Legionnaires' disease," said Joe Licotta, assistant superintendent of Harford schools.
Health Department officials insisted that the situation does not present a risk to the community, in part because of the precautions taken.
There have been two other incidents in which high readings of Legionella were reported in the past four years, according to Licotta.
Both cases involved air conditioner cooling towers and did not interrupt the daily operation of the schools.
Sun staff writer Justin Beck contributed to this article.