This year like last year, promises to be a much more controlled and less chaotic event.
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The city is again partnering with neighborhood merchants to control the mass gathering, which drew more then 10,000 festival goers last year.
Merchants have raised at least $200,000 to help the city pay for 183 portable toilets, 60 private security guards and clean up crews after the event.
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Expectations are that this year will draw even more participants because it comes on a Friday and it's the first time recreational pot smoking will be legal in the state.
Cannabis dispensaries are also expecting record sales on that day. Eliot Doris, spokesman for the Apothecarium dispensary on Market Street in San Francisco predicts it'll be the biggest 420 ever. "We have a whole new set of customers who are able to come to our dispensary, so we're expecting them to show up for the first legal 4/20," Doris said.
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The store plans to hold a special sale of discounts of up to 50 percent.
The same rules apply this year at the park. No one under 18 years old will be allowed inside, no tents, no unpermitted vendors, amplified sound or sale of marijuana or liquor in the venue.
VIDEO: Bigger crowds expected at SF 4/20 celebration now that cannabis is legal
There will be 20 public health approved vendors inside the meadow and the city will erect fencing for a mile around the perimeter of Robin Williams Meadow.
Eventgoers will have to come in from controlled check points.
SF Supervisors Prexy London Breed says there'll be more security, transportation, trash cans,portia potties at 4-20 blowout Friday in GG park. pic.twitter.com/KQuftzYSh1— Vic Lee (@vicleeabc7) April 18, 2018
San Francisco Board of Supervisors President London Breed said the city can't sanction 4/20 since smoking of any kind is not allowed in the park.
Whats more, the city can't stop the massive attendance, but Breed said at least the city can control it.
Last year, 4/20 was considered a success as there were no arrests and traffic congestion around the event was minimal.
VIDEO: San Francisco's 2017 4/20 celebration runs smoothly with no arrests
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