D.C.'s downtown L Street bike lane will get a twin this summer: a bike lane on M Street headed the opposite direction.

D.C. officials plan to install the lane in August, eliminating 40 to 80 parking spaces to do so.

The lane will look similar to the eastbound L Street bike lane installed in October, and will also use unique "mixing zones" that force drivers who want to turn to enter the bike lane near the intersection. But unlike L Street, the wider M Street will have parking on both sides, eliminating fewer spaces, and will run westbound to Georgetown from Thomas Circle.

The new lane on M Street was supposed to be installed at the same time as its partner on L, but was delayed.

"These projects have lots of pieces. We have limited staff working on them. That's really all we can handle -- one at a time," said Mike Goodno, who oversees bike lanes for the D.C. Department of Transportation.

Cyclists are excited to see the M Street lane open, since more bikers are expected to use the L Street lane in the summer, said Shane Farthing, president of the Washington Area Bicyclist Association.

"You're already seeing people using L Street going the wrong direction, and that can create a little bit of an unsafe situation," he said. "We really need M Street open."

D.C. doesn't have data on how many cyclists use the L Street lane, but it has counted as many as 355 cyclists per hour using the 15th Street bike lanes at P Street during the evening rush, Goodno said.

D.C. also plans to start construction this summer of a two-way protected bike lane on First Street Northeast, from Union Station to M Street.

That project won't be done until next spring, Goodno said, but when it's complete the District will have 5.6 miles of protected bike lanes.

Driver advocate and AAA-MidAtlantic spokesman John Townsend said he supports the bike lanes.

"We think the [cycling] trend is here to stay. ... Motorists have to become more sensitized to the presence of cyclists," Townsend said, adding that he would like to see D.C. invest more in roads. "We're not adding any more capacity for automobiles, and that is a great concern for many motorists."