It's called continuous flow metering, and the plan is designed to help reduce congestion on busy travel days.
On heavy traffic days CDOT Eisenhower/Johnson Tunnel Supervisor Rod Henderson says it's not safe to let traffic back up in the tunnel. If there's a car fire or someone needs help they just can't get to them, so they have to limit the number of cars and trucks in the tunnel.
"It allows us to take care of a problem if it occurs," Henderson said.
Last season, metering - stopping traffic and then letting some cars pass - caused huge delays. This year, we get continuous flow metering, meaning eastbound I-70 traffic will be funneled into four lanes right at the tunnel.
That's where four new traffic lights will come into play; two green will let some cars pass, while two red will stop traffic. Then three seconds later, they switch.
"We will have advanced warning signs and directions on signs and flaggers will be present," Henderson said.
The first test will be from 12:00 p.m. until 2:00 p.m. Saturday afternoon.
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