A dedicated bike lane will open along 15th Street in downtown Denver on Thursday, pushing all non-motorized two-wheeled traffic to the left side of the busy cross-town route.

It’s part of the 15th Street Bikeway pilot plan, designed to keep bicycles out of fast-moving vehicle traffic headed northwest across downtown Denver.

Bikes are allowed to ride in all lanes, which can create confusion.

“Autos and buses were never clear where to expect bikes to be traveling,” said Emily Snyder, manager of Denver Public Works’ Bicycle/Pedestrian Project.

The dedicated lane, buffered with a brick-colored strip, will run from Cleveland Place to Larimer Street.

“The main message is for motorists to look left,” Snyder said. “Little else changes for drivers, and it will make their commute easier.”

Whether the program expands to other busy streets depends on how well it works on 15th Street, public works spokeswoman Emily Williams said.

The lanes are also designed to get bikes off sidewalks, where some cyclists move during heavy rush-hour traffic.

“Sidewalks are very dangerous places to be, because motorists don’t expect cyclists to be on sidewalks or moving off the sidewalk into the crosswalk,” Williams said.

The new bikeway is modeled on those successfully deployed in cities including Minneapolis, Portland, Ore., San Francisco, Chicago and New York, Snyder said.

Although the initial days of the project probably will be confusing for cyclists and motorists, the cycling community is supportive, said BikeDenver executive director Molly North.

“We think the city did a great job planning this corridor,” North said. “It’s a really great illustration of a coordinated effort to prioritize bicycling as a viable mode of transportation.”

The most confounding element of the new traffic pattern probably will be the intersection of 15th and Lawrence streets, where there are two bike-only traffic signals — one in the bike lane, the other diagonal from the bike lane.

For example, cyclists who want to head to the Cherry Creek Trail at Larimer Street, one block away, will wait for the bike-only signal in the bikeway to turn green, then move straight through the intersection. Cyclists headed toward Lower Downtown or beyond will wait for the diagonal signal to turn green and then ride diagonally across the intersection and position themselves along the right side of 15th Street.

After Larimer Street, the bike route shares lanes with motorized vehicles.

Green pavement along 15th Street will highlight areas of shared space and raise awareness of potential conflicts in turning movements.

There will be five mixing zones — at Tremont, Glenarm, California, Champa, and Arapahoe streets — where motorists who want to make left turns must merge into the bikeway.

Cyclists who want to turn right from the left-side bikeway onto Welton and Lawrence streets can make a “vehicular style” turn — looking for traffic on the right and then crossing — or use green queue boxes to position themselves in shared lanes and wait for the traffic signal to change.

A bike box — a large, green square painted on the pavement on Cleveland Place — is designed to increase the visibility of cyclists stopped at the traffic signal and give priority to cyclists who enter into the intersection on the green light.

Although the changes might sound confusing to some people, North believes things will go smoothly. “It’s pretty intuitive,” she said.

Still, volunteers will be stationed on corners along 15th Street on Thursday and Friday to answer questions from motorists and cyclists. Williams said if the transition is rocky, volunteers will be deployed again next week.

Colleen O’Connor: 303-954-1083, coconnor@ denverpost.com or twitter.com/coconnordp

Feedback

The concept of the 15th Street Bikeway could be deployed on other high-traffic Denver arterials, so traffic managers are asking for feedback.

Starting Thursday, you can weigh in at denvergov.org/bikeprogram.