Drivers can test out Elmhurst Road diverging diamond intersection Friday
After months of preparation, Illinois tollway and state engineers will throw the switch on an innovative diverging diamond configuration on Elmhurst Road at I-90 Friday morning.
The technology requires drivers to think counterintuitively as they will briefly switch onto the left side of the road to avoid making turns against oncoming vehicles.
The new traffic pattern will go live after 9 a.m. when all traffic on Elmhurst Road near the Jane Addams Tollway interchange will be stopped for about 10 to 15 minutes so workers can add final striping.
Ramps to the toll road, however, will be closed to monitor traffic flow and signals until next week.
The unusual design uses traffic lights to guide vehicles temporarily into the left lanes to avoid making turns against oncoming vehicles. It will be the third such interchange in Illinois; one is operating at I-88 and Route 59, and another is in downstate Marion.
The configuration is considered safer and uses less land than conventional cloverleaf designs.
On Monday, two rebuilt I-90 ramps carrying vehicles to and from the east will reopen, and on Tuesday, two new ramps taking traffic to and from the west will be accessible.
Drivers will need to have I-PASS transponders or pay online as the interchange is all-electronic. Tolls on the ramps to and from the west cost 55 cents for I-PASS users and $1.10 if you pay in cash.