Cops, City Hall and lawmakers are bracing for Thursday’s onset of legalized “recreational” marijuana in Massachusetts, determined that if they can’t dissuade tokers from lighting up they can at least provide information plus some vigilant law enforcement to try to keep people safe.

Bay Staters voted last month to permit adults 21 and older to possess up to an ounce of weed while out in public — 10 ounces at home — while cultivating up to 12 plants per household. Selling pot remains illegal while the Legislature works on regulations to license retailers.

And while pot-opposing Mayor Martin J. Walsh told the Herald he believes “some people who took that vote will regret it some day,” his administration has launched a website — www.boston.gov/departments/311/marijuana-legalization-and-city-boston — to answer people’s questions about legal pot.

City Hall also plans to turn to Twitter Thursday with graphics designed to inform people how the new law works.

“The voters spoke. I’m going to support the will of the voter, obviously,” Walsh told the Herald yesterday. “There are some major concerns we have … I don’t think it was well-thought out when it was put on the ballot … Now it’s legal, so if you’re smoking a joint in your car and you’re driving down the street, and a police officer pulls you over for whatever reason, nothing they can do about the joint. At least if you have an open container of alcohol in the car, the police can take action. Those are questions we’re going to have to figure out.”

But driving stoned is still illegal.

State police spokesman David Procopio said legalization “does not mean that is OK or legal to drive under the influence of marijuana or to smoke or consume it while driving. Operating a motor vehicle during or after use of marijuana remains illegal and extremely dangerous to the driver, his or her passengers, and the other motorists around them. We will be very aggressively looking for any vehicles being operated erratically, and our troopers are trained in observing the physiological effects of impairment and drug use.”

Smoking pot — like smoking tobacco — is illegal in Boston parks and any city property, as well as in restaurants, bars and public spaces, Lt. Michael McCarthy said. He added police “will enforce the prohibition on persons under the age of 21.” Moving forward, he said the department “will work closely” with the future state-appointed Cannabis Control Commission “to oversee the process of legalization.”

Lizzy Guyton, spokeswoman for Gov. Charlie Baker, who like Walsh opposed legalizing pot, said, “The administration will continue to work closely with lawmakers, educators and public safety and public health professionals on the implementation of the law to ensure the transition protects the interests of our communities and families while adhering to the will of the voters.”