New E. coli test to be used at city beaches
MARQUETTE – A new water-quality test being rolled out by the U.S. Environmental Protection Agency will be used in Marquette this summer and should help to limit unnecessary beach closures, according to officials.
The new test, developed by the EPA, will allow the city to determine the quality of a given water sample in three hours. The conventional test, which the city has used for years, takes about 24 hours.
Marquette was involved in a pilot program for the rapid test last year and utilized the method a handful of times near the end of the summer.
“We did a couple of rounds of it,” said Curt Goodman, the head of the city’s Water/Wastewater Department. “(The EPA was) gathering data to be sure the test meets all standards.”
Twice weekly during swimming season, city staff take water samples from the main Marquette beaches. If the average of three samples from a single beach shows more than 300 parts E. coli per 100 ml of water, state regulations indicate the beach must be closed until the levels decrease.
With the conventional test, the city can’t determine whether the levels have decreased until at least 24 hours after the first results are known. This means that beaches may be closed for a day or more, despite low bacteria levels.
The new test, according to Goodman, should create fewer unnecessary beach closures.
“We’re going to sample the beaches probably twice a week and we’re going to continue on doing the rapid test once a week,” he said.
If an exceedance is recorded, the city should know within a few hours if the beach should be closed for the day.
The new test is recommended, but not required, by the EPA.
The beach testing done in Marquette is not mandated by the state, but is done in conjunction with a grant from the Michigan Department of Environmental Quality and Goodman has said the city operates the only testing operation in Marquette County.
Though Michigan law stipuates the closure of beaches with 300 parts E. coli per 100 ml of water, Goodman said other states, including Wisconsin, are only required to post a warning sign at that level.
Wisconsin beaches, he said, aren’t closed unless the test shows more than 1,000 parts per 100 ml.
The city’s water-testing initiative identified a number of overages – and thus led to a number of beach closures – last summer, including at the city’s South Beach on five separate dates.
Scientists from the U.S. Geological Survey analyzed the new rapid test, using data from five Lake Michigan beaches, and determined that the test was accurate and may, indeed limit beach closures.
“Our research shows that EPA’s rapid test can be an effective tool for beach managers to help keep their recreational beach goers happy and safe,” USGS scientist Meredith Nevers said in a written statement.
Kyle Whitney can be reached at 906-228-2500, ext. 250.