Waymo cars have been all over central San Diego for more than a year, but always with drivers at the wheel. Ready or not, that’s about to change. The company said Wednesday that Waymo vehicles will soon begin fully autonomous operations — meaning without human drivers — in four new cities, including San Diego. It will be a soft start, with rider-only operations initially offered solely for employees. Waymo, in a blog post, said only that it expects “to welcome the public soon.” Officials with the venture, which is majority owned by Alphabet, Google’s parent company, said local residents can learn when Waymo goes live to the public by downloading the app for notifications. The other new cities in Waymo’s expansion are Las Vegas, Tampa and Denver. Ten other cities and regions, including the Bay Area, Los Angeles, Phoenix, Dallas and Houston already offer Waymo driverless rides. Waymo is the leader among the handful of companies offering robotaxi services, an innovation that some have embraced enthusiastically, but others are wary of for safety and economic reasons. Some critics fear software glitches and erratic maneuvers that could cause wrecks, while others are concerned about the impact on the fortunes of human drivers. A San Diego councilman, Sean Elo-Rivera, in his role as a member of the regional transit board, challenged Waymo’s impending arrival, successfully persuading the board to oppose the expansion of driverless services in greater San Diego without more oversight. The board also called on the state Legislature and regulators to intervene. “No corporation should be allowed to quietly replace people with machines just to boost profits, especially without local communities having any say,” said Elo-Rivera, chair of the board’s Taxi Advisory Committee in a January news release. On the safety front, though, Waymo and other driverless vehicle services have