Cyclists in Boulder are going green -- in more ways than one.

Last Thursday, the city of Boulder began applying a bright green road treatment to bike lanes in an effort to reduce the number of collisions between vehicles and cyclists, according to city transportation operations engineer Bill Cowern. The idea is that the bright streak of green will make drivers more aware of bike lanes next to them, he said.

The city transportation department applied the initial bright green treatments -- which cost around $2,300 a piece -- at the intersections of Folsom Street and Canyon Boulevard, and Folsom and Pearl Street. The Safe Streets Boulder study, released by the city in February, found these two intersections had some of the highest rates of vehicle collisions with bikes and pedestrians in the city.

Between January 2008 and October 2011, the two locations had a combined 17 collisions, according to the study.

In these two locations, Cowern said drivers turning right often don't see a cyclist in the bike lane next to them and end up "hooking" in front of a cyclist, who must try to avoid hitting or being struck by the moving vehicle.

"The hope is that the bike lanes give the driver that added clue to watch for bikes, to look in the rearview mirror and make sure they're not cutting one off," Cowern said.

The bright green color is standard as set by a federal road and traffic manual, the Manual on Uniform Traffic Control Devices. Green is the universal color for bike lane treatments, Cowern said.

The city has no timeline in place for adding more green bike lanes, Cowern said, emphasizing that the project is "definitely still an experiment." The next intersection the city will target is Colorado Avenue and Regent Drive, which had the highest accident rate (11) according to the safety study.

In order to determine the treatment's effectiveness, Cowern said the transportation department will use field observation, videotaping, an online survey and other methods to see if the number of accidents decreases.

If the bike lane treatments don't prove effective, the city will let nature fade the bright green coloring, he added.

The material used to cover the two bike lanes is a pre-formed thermoplastic material, or a sheet of pre-cut green plastic that city employees melted onto the asphalt, Cowern said.

Many cyclists and commuters were concerned that adding materials to the road would make it slippery in the rain.

Kris Thompson, who runs the cycling website 303Cycling.com, said he wondered why the city didn't implement full-on bike boxes like other cities.

"This is just a green bike lane," Thompson said. "Yes, it does raise awareness, so I guess drivers will see it. But it seems like it goes only halfway. I don't know why they were afraid to implement the same solution that Portland had implemented. I'm not going to complain. It's better than nothing."

In cities like Portland, green bike boxes were installed with the same intent of reducing the number of right-turn collisions. These bike boxes extend past the bike lane and are painted in front of cars that are stopped at a red light, forming a green L-shaped path. During a red light, bikers pull ahead of the stopped cars into the box, and drivers must wait for the bikes to exit the box before turning right.

"It has an anti-skid surface embedded in its top layer, so it's built to resist skidding," Cowern said, adding that this material is just one of many that the city hopes to experiment with in the coming months.

Peter Chisholm, owner of Vecchio's Bicicletteria, said he hadn't ridden on the green stripes yet, but was intrigued by the idea.

"Anything that lets people in cars know that there are people on bikes nearby -- how could it be a bad thing?" he asked.

--Follow Sarah Kuta on Twitter: @SarahKuta