What's Happening in San Francisco, CA…

Marin County, including San Francisco, is set to monitor the speed of mountain bikes and other bicycles on the country's trails and in open spaces.

Officials have previously had no way to accurately measure riders' speeds, but that will change soon, since deputies are scheduled to start using both radar and LIDAR this spring.

LIDAR (the acronym stands for “light detection and ranging” as opposed to the RADAR acronym “radio detection and ranging”), is more accurate than radar and uses laser light to measure distances. LIDAR has been in use on the Mill Valley-Sausalito Multiuse Pathway since May 2015.

Since LIDAR was implemented, incidents related to both riders' speeds and users’ complaints have declined. Pat O'Brien, the interim director of Marin County Parks, said even though most bicyclists take care to ride safely on the open space trails, using LIDAR was a natural development in the open space reserves. Max Korten, also with the parks agency, said speeders would be warned for now, and it is not known when tickets will be issued.

County officials might like to work with a brochure printing company to explain the new policy. They could include maps of the trails and open spaces that will soon be patrolled, and ask riders to observe safety regulations and remain courteous to others who use the trails alongside them.