August 28, 2012
beach advisories predictable, accurate - and timely
MADISON -- A Wisconsin research scientist is working to inject some real-time information into easily-accessible updates about the condition of your favorite Great Lakes beach.
When and why a Great Lakes beach gets posted for a swim advisory or closure in 2013 may be the product of a new virtual beach system that saves money and gets current, accurate water quality updates to the public.
"On many occasions, the local beach manager will post an advisory or close the beach when it is not necessary," says Adam Mednick, a research scientist with the Wisconsin Department of Natural Resources. "And that same manager will not post an advisory or closing when, in actuality, the concentrations of E.coli would show a heightened health risk."
This isn't a case of an incompetent beach manager. This is a case of an inadequate and ineffective method to determine when elevated levels of certain bacteria - including the fecal indicator E. coli and Enterococcus - pose threats to humans.
"The problem rests in the current routine water monitoring procedure. By the time health officials collect samples and culture for these bacteria, it can take 18 to 24 hours," Mednick says. "The beach managers use those results as the basis for posting the swim advisories or the beach closings."
And, a lot can happen in 18 to 24 hours. What happened yesterday may not be the case today, meaning the rock-solid analysis done through the routine analysis likely has lost its punch by the next day.
Mednick says the issue is that time lag between when the water samples are taken and the time it takes to run the lab analysis. Mednick says the lag can bring a results are "frequently inaccurate -- not that the lab results are inaccurate," he says, "but that they are a day-old and those conditions may not exist anymore."
An analysis of the data used in Wisconsin from 2003 to 2009 for beach closings or advisories shows more than 60 percent of those closings were not needed. And, more than 10 percent of water samples collected on days when there was neither a swim advisory nor a closure indicated there should have been one.
Not only do beach restrictions make it harder to find cool relief on hot days, local tourism businesses that rely upon active beachfronts also take a hit.
Wisconsin has 124 beaches along the Great Lakes which are monitored by local health agencies under the federal BEACH Act. DNR is the state coordinator of this federal program that calls for swim advisories and beach closings when E. coli levels exceed certain levels.
Three years ago, Mednick started working with his counterparts at the U.S. Environmental Protection Agency and the U.S. Geological Survey on a way to pick up the pace to help local beach managers more effectively determine the need for advisories or all-out closings.
It's called Nowcasting.
Mednick calls Nowcasting an early warning system.
"It is a real-time estimate of water quality conditions. We can do this using statistical models," he says. "We can predict water quality and specifically E. coli concentrations and also the probability of exceeding water quality guidelines."
Using a free EPA software system called Virtual Beach, which he has been instrumental in helping EPA to make more user-friendly and operational, Mednick has worked with local partners to create customized models for individual beaches. Local managers can operate the models to predict - or Nowcast - when conditions may be ripe for problems.
The system was first used in Wisconsin in 2009 in Ozaukee County at Port Washington.
DNR worked with the county's public health department to put in a Nowcast system based upon the Virtual Beach software. Local officials say the system has worked well and requires less than five minutes of department staff time each day to use. It has become part of their routine monitoring and public notification activities. This is not only good news for beach lovers, but for the taxpayers as well who support the public beaches.
And the results are solid. So impressive are these early tests of the program by local beach managers, Nowcasting also is set to get the State Program Innovations Award from the Environmental Council of the States at its national meeting on August 27 in Colorado Springs, Colo.
In 2011, operating at two pilot beaches, water-quality Nowcasts reduced the number of missed advisories by 20 percent and incorrectly-posted advisories by 50 percent. This summer, Nowcasts are being used at seven high-priority beaches on Lake Michigan and have been developed and tested for an additional 20 beaches on Lake Michigan and Lake Superior by DNR and USGS in preparation for expanded implementation next summer.
"This is a genuine step forward in water quality monitoring that directly affects beach-goers and the local economy," Mednick says.
The DNR maintains a user-friendly page that shows the current conditions at the Great Lakes beaches (exit DNR).
The DNR offers a guide for you to use when planning a trip to any of the Great Lakes beaches in the state.
FOR MORE INFORMATION CONTACT: Adam Mednick, 608-261-6416, or Joanne M. Haas, public affairs manager for science services, 608-267-0798