A medical marijuana storefront dispensary approved for 3617 State St. will be one of just three permitted under a Santa Barbara ordinance. (Noozhawk file photo)

Unthinkable only a couple of decades ago, California has joined several other states in legalizing the recreational use of marijuana.

Voters on Nov. 8 approved Proposition 64, the Adult Use of Marijuana Act, 56.5 percent to 43.5 percent, according to the Secretary of State’s Office. The law went into effect the next day.

Despite the hype surrounding the new law, marijuana use will still be subject to plenty of restrictions.

People age 21 and older can use the substance in private homes and at businesses licensed for on-site marijuana use. Individuals can grow up to six plants in their residences as long as they’re locked up and out of sight.

Possession can’t exceed 28.5 grams, or about an ounce. For concentrated marijuana like hash, possession can’t exceed eight grams.

Use is barred in public places, where tobacco smoking already is prohibited, and at schools, day care and youth centers where children are present.

Businesses, which can start receiving their licenses in 2018, cannot set up shop within 600 feet of schools or day care and youth centers.

In Santa Barbara, however, recreational businesses are temporarily banned until September 2018 as officials work out local regulations for them.

California’s prominent medical marijuana industry has been around for 20 years, and the Justice Department under President Barack Obama has declined to prosecute medical marijuana users even though their possession is still illegal at the federal level.

At the beginning of the year, the City of Santa Barbara approved rules limiting medical marijuana cultivation to 100 square feet for qualified patients at their own residences.

The city also has a dispensary ordinance covering medical marijuana storefronts, permitting up to three to operate, each of which must be located in a different pre-determined zone.

Proponents argued that tight and numerous restrictions protect children, and that new taxes provide funds for youth programs, law enforcement and environmental protections in a state where prospective pot users had few obstacles to acquiring the substance.

A chief fear of opponents of the new state law is an increase in traffic crashes and deaths caused by impaired drivers.

“I’m scared about this one — mainly for the increase in vehicle fatalities,” Santa Barbara Police Chief Lori Luhnow said at a community forum Monday. “We will be increasing our staffing and traffic division, specifically because of the issues we have and with Prop. 64.”

While the dangers of drinking and driving are well known, there is not the same kind of taboo around driving high, police Sgt. Riley Harwood said.

“With the appropriate educational efforts, hopefully we’ll have that same kind of mindset that we have with regard to drinking and driving,” he told Noozhawk.

Part of a $250,000 grant that SBPD received earlier this month from the state Office of Traffic Safety will go toward DUI-related training and enforcement.

While driving under the influence is SBPD’s top concern, marijuana in general has been one of the lowest priorities, Harwood said.

Because of that, District Attorney Joyce Dudley told Noozhawk, few marijuana-related cases come through her office.

Like Luhnow, however, Dudley said she now expects to see an increase in DUI-related cases.

Local enforcement practices won’t change much, but neither will the drug-testing practices at the Santa Barbara Metropolitan Transit District, which operates the South Coast’s bus services.

Because the agency receives federal funding — and marijuana is still illegal on the federal level — drivers, mechanics and dispatchers are still required to abstain from cannabis use, said Steve Maas, MTD’s manager of government relations and compliance.

Federal law requires that MTD drug-test employees, he said, which can happen pre-employment, post-accidents, with reasonable suspicion or at random times.

Police aren’t expecting a sudden increase in calls for service, Harwood said; smoking in public — which is still barred under Prop. 64 — already accounted for the vast majority of marijuana-related calls, he said.

“In Santa Barbara, we’re always concerned about how this is going to impact the quality of life in our community,” he said.

Where in the city pot may eventually be sold contributes to this concern, he added, as well as illegal selling operations that spring up.

“Any time you have a commodity that’s heavily taxed, you often see a black market develop,” Harwood said.

Per the new law, selling without a license can mean up to six months in jail and/or a fine of up to $500.

Meanwhile, those serving sentences for actions that are now legal or are now subject to a lighter punishment are eligible for resentencing.

On the commercial side, the new state law prohibits businesses from selling pot if they also sell tobacco and alcohol, and prohibits them from allowing patrons to use marijuana on-site if tobacco and alcohol use are also allowed.

Going into effect Jan. 1, 2018 — the same time as business licenses are to go out — will be new state taxes on recreational and medicinal marijuana.

A $9.25-per-ounce growing tax will be placed on dried marijuana flowers, and dried marijuana leaves will see a $2.75-per-ounce growing tax.

Additionally, a 15-percent excise tax will be placed on the substance’s retail price, and on Election Day, Santa Barbara voters approved a 20-percent tax on the gross receipts of medical- and recreational-pot businesses.

Along with covering the new administrative costs, revenue from state taxes is to go toward youth and public-health programs, environmental cleanup and law enforcement and DUI programs. Santa Barbara’s 20-percent tax will be added to general city services.

Although various facets of marijuana use and business will be overseen by a handful of state agencies, the main regulator is the Bureau of Marijuana Control, known now as the Bureau of Medical Cannabis Regulation.

— Noozhawk staff writer Sam Goldman can be reached at sgoldman@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.