GILROY
– City officials believe they have solved the problem with an
often-stuck left-turn arrow at Tenth and Chestnuts streets that has
caused several traffic jams in recent weeks.
GILROY – City officials believe they have solved the problem with an often-stuck left-turn arrow at Tenth and Chestnuts streets that has caused several traffic jams in recent weeks.
Traffic Engineer Kristi Abrams says strobe light devices atop regular automobiles – but designed for rescue vehicles – are causing optical sensors atop traffic signals to jam.
Abrams discovered the problem after responding to complaints about the signal at Tenth and Chestnut. She said she noticed a bus with a strobe light get a green light and pass through the intersection. Once it did, the turn arrow that had been the focus of complaints stayed red.
The $300 strobe lights can be purchased on the street and are becoming more common atop the cars of motorists who want to avoid waiting for lights to change, said Abrams.
“I was flabbergasted when I found this out,” Abrams said.
Abrams said the city is now researching how much it will cost to replace the optical sensors above traffic signals with more updated programmable units. The new units would be able to recognize a strobing signature emitted from rescue vehicles.
Last week, after problems with the light were reported to the city, the leading theory on what was causing the problem was that certain underground magnetic loops – which sense vehicles above ground and cause the lights to change – were not sensitive enough.
Abrams figured this since some of the complaints came from drivers of large trucks. Tall tires on trucks make the chassis sit high above the ground. This distance makes it difficult for the magnets underground to sense the presence of a vehicle, meaning the arrow stays red.
The city made those loops more sensitive, but last week Abrams spent time observing the intersection and saw the magnets were not the problem.
Abrams encourages drivers to call whenever they notice a problem with traffic signals. Hotlines for each type of intersection in Gilroy follow:
• For intersections maintained by the city, call Republic Electric at (800) 544-4876.
• For intersections maintained by Caltrans, call (415) 330-6509 or (415) 330-6500 during normal working hours or (510) 286-6356 or (510) 286-6359 after normal working hours.
• For intersections maintained by the County, call 299-3604 during normal working hours and 299-2507 after normal working hours.
To find out which agency maintains each intersection in Gilroy, visit www.gilroydispatch.com.
