California Invented 'Botts' Dots' Raised Pavement Markers—Now it's Phasing Them Out

"Botts’ Dots – the raised, rumbly markers between lanes on California’s highways and freeways  – are on their way out, with Caltrans saying it will no longer maintain or install them," reports Jonathan Winslow.

Botts' Dots are named for Elbert Dysart Botts, whose research in the 1950s led to the long-term implementation of the dots, both in California and around the country.

The old technology is now being phased out, on the recommendation of federal transit officials (usually issues of pavement markings comes under the purview of the Federal Highway Administration). "Critics say the ceramic buttons aren’t reflective, don’t really help that much, mess up autonomous cars and don’t last very long," according to Winslow.

Winslow is able to find at least one driver who credits the rumble created by the raised dots from keeping them alert while driving. The state, however, has found little evidence to dispute the opinions of the feds on the matter.

There remain 20 million dots on California highways and freeways, and they'll be allowed to slowly disappear, though some cities will still use them, according to Winslow. 

For more on the demise of Botts' Dots, see also coverage by Gary Richards in February and Tony Bizjak in January.