Glen Ellyn Park District has discontinued use of a lightning prediction system at five parks because of ongoing malfunctions and unpredictable readings, officials said.
The Thor Guard system was installed at five locations in 2002 and another two spots in 2004, but has become increasingly unreliable, often sounding its airhorn alarms when there's no storm in sight.
The district said this week that it will discontinue use of the system at Ackerman Park, Village Green Park, Newton Park, the Main Street Recreation Center and Lake Ellyn Park. The system, however, will remain in place this summer at Sunset Pool and Maryknoll Park, where it has provided credible warnings, officials said.
The system is designed to provide warnings via airhorns and strobe lights 8 to 20 minutes before a storm, but there have been mixed reviews on how accurate it is, Dave Harris, the park district's executive director, said at a recent meeting.
At Ackerman Park, the system often has operated with "inconsistent predictability," and it's believed the high electrical wires and elevation of the property causes the system to generate false readings, according to the park district announcement.
The district's staff has replaced numerous parts over the years -- at a cost of $1,000 last year alone -- and spent time cleaning the system's sensors, which is necessary about every three weeks to clear it of pine needles, spider webs and diesel particles that can cause false alarms, officials said.
"We don't want to be having a system in place that either provides a false sense of security or that's not going to be credible and people are just going to ignore it," Harris said.
But there haven't been similar false alarms at Sunset Pool and Maryknoll Park, where the system has been reliable and park district staff has the ability "to use something other than their own instincts or monitoring a website or smartphones," Harris said.
So the district will be keeping the system in place at those two locations this summer while staff members continue evaluations this fall.
Harris said the district has informed athletic groups, rental groups and other park users that the lightning warning system will not be in place at the five park locations, and is urging them to take other precautions to monitor the weather.
The district's severe storm policy, in the absence of Thor Guard, states that all games, practices and park activities must be immediately suspended if any thunder is heard or lightning seen -- regardless of how far away it is believed to be -- then wait 30 minutes without another spotting before play resumes.
District officials are evaluating whether to replace the current system with Strike Guard, a lightning detection system that they say is different from the Thor Guard lightning warning system. They've already spoken with other area park districts to get feedback on their experiences with both.
The Naperville Park District decided to keep Thor Guard in place at Centennial Beach, but removed it from parks and replaced with it with Strike Guard.
The Palatine Park District spent more than $100,000 two years ago to install Strike Guard in all of its parks, but was dissatisfied with Thor Guard at shared outdoor spaces with the Palatine school district.
It would cost the Glen Ellyn Park District $36,000 to purchase the Strike Guard equipment, plus costs to install it at the locations that now have the other system.
The district paid $26,650 in 2002 and $5,000 in 2004 for the Thor Guard equipment.