A new bike lane mysteriously appeared on Saskatchewan Drive overnight, winning praise from cyclists and a stern warning from city officials on Thursday.

"I think it's important to have a space for cyclists that's safe," said cyclist Debbie Bellerose.

"Unfortunately someone took it into their own hands, but I don't see any harm in it and perhaps it'll make a statement for the city to take a more proactive stance."

The amateur road engineer(s) rolled yellow tape down the centre of the shoulder on the south side of Saskatchewan Drive east of 109th Street.

They painted bike-lane symbols onto the pavement and separated the lanes from vehicle traffic with cones lifted from a  construction site across the road.

Chuck Dickens

Road maintenance supervisor Chuck Dickens removes the 'centre line' from the guerilla bike lanes Thursday. (CBC)

The city was quick to remove the rogue lane though, especially since it blocked an active bus stop.

"Someone had taken it upon themselves to make it a two-lane directional bike lane," said city road maintenance supervisor Chuck Dickens, who was tasked with getting rid of it.

"They used a little bit of tape and paint and got creative and made themselves up a little bike lane."

Rogue lines are illegal

Conrad Nobert is the chair of Paths For People, a group that advocates for safe spaces for cyclists and pedestrians. He said the crackdown was unfortunate, given that the city often takes years to build new bike infrastructure.

"This little piece of guerilla urbanism I see as a symptom of a bigger problem," Nobert said.

He said the area is incredibly popular among cyclists, but the infrastructure isn't safe or well designed for people on bikes.

Daniel Vriend, city supervisor for urban transportation, said his department is working on widening the mixed-use path on the north side of the road to respond to the demand from cyclists.

More details should be available this summer, he said.

In the meantime, he wants to remind Edmontonians that installing guerilla bike lanes is illegal.

"Obviously, our primary concern is that anything out on the road is going to operate safely," Vriend said.

If someone does want to install a temporary bike lane, Vriend recommends applying for a permit from the city.