The Centers for Disease Control has said that hospitalizations due to three types of waterborne diseases cost the US health care system around 539 million dollars a year.
The CDC said relatively small expenditures to improve water systems and keep swimming pools clean could dramatically reduce the incidence of the three diseases: Legionnaire's disease, cryptosporidiosis and giardiasis.
The average cost of treating one patient hospitalized with Legionnaire's disease was more than 34,000 dollars, the CDC said.
The costs associated with treating each illness were gleaned from a database of health care claims submitted between 2004 and 2007.
"When people think about these diseases, they usually think of a simple case of diarrhea, which is a nuisance, but quickly goes away," said Michael Beach of the CDC, an author of the study.
"However, these infections can cause severe illness that often results in hospital stays of more than a week, which can quickly drive up health care costs."
The illnesses produce symptoms ranging from rashes and eye and ear infections to serious respiratory and neurological problems that can prove fatal.
"Modest investments in preventing the diseases could lead to reduced disease and significant health care cost savings," the study said.
Beach recommended "public education campaigns, appropriate maintenance of building water systems, and regular inspection of pools and other recreational water facilities."
In a May news release, the CDC warned that a 2008 study conducted in 13 US states forced the closure of one in eight public pools for public health and safety code violations.
Of the 112,000 pools inspected, some 12.1 percent, or 13,500 facilities, were found to be in serious violation of health and safety codes and were immediately closed down.