A police investigator works around a tent covering the scene of a bicycle death Aug. 18 in Harvard Square – where the city now plans to add a separated bike lane. (Photo: Marc Levy)

Traffic through the heart of Harvard Square is going down to one lane in each direction, from two, as a result of a bicyclist death last week, the Community Development Department announced Tuesday.

The bicyclist died early Aug. 18 in a crash after being hit by a tractor-trailer near the Harvard Square T Station. Other details are scant, and authorities haven’t publicized the name of the bicyclist, reportedly a man in his 50s. The crash took place at approximately 9:42 a.m. with a truck labeled as being from Gaby’s Elite Transport out of Rio Rancho, New Mexico.

Staff “conducted a preliminary site visit” after the crash and identified quick-build improvements to make, which included cutting the number of traffic lanes in half; a separated bike lane will be installed in the newly created space on the Harvard Yard side of Massachusetts Avenue near the T station and Harvard Square Kiosk. The northbound changes near Harvard Yard will be implemented in two weeks, and the southbound changes will come shortly afterward, according to Community Development Department.

Officially, the changes are tied to long-term improvement being planned for the kiosk (until recently the home of the Out of Town News stand) and plaza, for which contractor bids are due in mid-September, the department said.

“I’m hopeful that these projects will better protect Cambridge’s cyclists and pedestrians and restore a feeling of safety, but city action can’t stop at these quick-build improvements, or at the borders of Harvard Square,” vice mayor Alanna Mallon said in an email.