SAN JOSE -- San Jose leaders have taken their firmest stance yet on one of the thorniest issues at City Hall, moving to crack down big time on medical marijuana dispensaries following several failed attempts to get tough on pot over the last half-decade.

The San Jose City Council's 7-3 vote Tuesday evening limits existing and new pot shops to a handful of select industrial areas that make up less than 1 percent of the city, which will require the vast majority of the dispensaries to close within a year. Even the ones that survive will have to comply with costly new restrictions.

Dispensary opponents led by some parents, prosecutors, conventional business owners and school officials pointed to research showing kids in San Jose were getting their weed from the pot shops, either through illegal drug deals or by obtaining medical cards. They said the city's roughly 80 weed businesses were also destroying the character of suburban neighborhoods, attracting crime and blight.

"I think we came up with something that protects our residents," Councilman Pete Constant said, while still "providing enough space for dispensaries to operate."

While 60 percent of respondents in a city-commissioned poll earlier this year wanted pot shops regulated, only 16 percent favored an outright ban already adopted by about 200 California cities. But a ban is exactly what will happen, marijuana store owners say, as the new regulations will make it virtually impossible to do business in San Jose.

The requirements force pot shops to grow all weed in or next to Santa Clara County, limit store hours and set up round-the-clock security. What's more, no one under 18 can be allowed inside or to work for dispensaries, the shops can't offer products that imitate candy and customers can't get high in the store.

"Nobody can operate under those environments," said James Anthony, an attorney representing many of the pot shops. "It's a de-facto ban and in kind of a sneaky way."

Pot business owners say they have collected more than enough signatures necessary to put their own dispensary rules -- with looser regulations -- on the ballot, Anthony says. They note the city makes $5.4 million in tax revenue from the pot shops and insist the issues are limited to a few problem shops. They were aiming to place the initiative on the November ballot, but the council could delay it to November 2016.

A similar scenario played out in 2011, when the council followed years of discussion by voting for dispensary limits only to back off them when a referendum qualified for the ballot. Since then, however, a Supreme Court ruling and guidelines issued by the U.S. Attorney General's Office have given cities new authority to regulate pot shops, and the council says it's not backing off this time. Mayor Chuck Reed has even vowed to lead the fundraising campaign against the pot groups' ballot measure.

San Jose has the bulk of Silicon Valley's pot shops thanks in part to its lack of action on regulations. Officials in Gilroy, Los Gatos, Milpitas, Morgan Hill and Sunnyvale have banned pot shops, according to Americans for Safe Access. The Santa Clara County Board of Supervisors is set to consider a ban in unincorporated areas this summer.

In San Francisco and Oakland, officials have enacted regulations but they are generally not as strict as what San Jose approved Tuesday.

Under San Jose's new rules, the stores must be more than 1,000 feet away from schools, parks and other areas children gather; 1,000 feet from certain major business parks; 150 feet from homes; and 500 feet from substance abuse centers. That leaves about 600 parcels, mostly in North San Jose and the central part of the city just east of Highway 87.

As a result, the one-fourth of the city's dispensaries that are next to homes could be forced to close in the coming months. Most of the others will also find themselves in no-pot zones but will have until summer 2015 before they have to shut down. About five to 10 could potentially stay in their current locations.

During the last five weeks, the council has on four occasions had the final plan up for debate -- totaling more than 10 hours of discussion -- but delayed a decision. Each time, medical pot supporters wearing green cannabis leaf T-shirts flooded the council chambers alongside their opponents. On Tuesday, Councilmen Ash Kalra, Don Rocha and Xavier Campos were opposed, and Kansen Chu was absent.

Contact Mike Rosenberg at 408-920-5705. Follow him at Twitter.com/rosenbergmerc.