An annual pro-pot party will still go ahead this week despite opposition from Vancouver's park board.

In a statement issued Tuesday, the board said it refused organizers' request for a permit for reasons including that the 4/20 festival violates smoking bylaws. The board said the event expected to bring tens of thousands to Sunset Beach Park has negative consequences for other park-goers and for the park itself.

Last year, a crowd of about 40,000 racked up a bill of about $245,000 in costs including policing and re-seeding a trampled lawn. But the head organizer told CTV News that after paying for security, toilets, garbage collection and other services, there was only $18 left in the budget.

Despite the board's condemnation of the event, however, the 4/20 protest will go ahead on Friday.

"It's just one time a year," said organizer and long-time activist Dana Larsen.

"I think cannabis users have a right to use public spaces like everybody else. The people who come down here and enjoy the event are also a part of Vancouver. We're also citizens and we have a right to use these spaces."

The park board said it will do its part to ensure public safety and to minimize the impact on the park and others trying to enjoy it.

"This is a public park. It's designed for everyone. We have no smoking bylaws and those are in place for a reason. It's for the health and safety of everyone," board chair Stuart Mackinnon told CTV News.

Commissioners are looking at ways to better protect the soggy turf in the park this year, including a protective covering around the main stage that will be paid for by organizers.

In a Facebook post, organizers said the covering will cost about $30,000, and that they expect it to eliminate the risk of damaging the grass. They've also hired a group that sorts garbage and recycling to reduce the event's carbon footprint.

In the days leading up to the gathering, park rangers will be delivering leaflets to those who live in the area to make sure residents are informed of the likely crowds, traffic delays and potential health impacts for those sensitive to smoke.

The adjacent seawall, Sunset Concession and Vancouver Aquatic Centre will be closed the day of the event, the park board said.

Representatives of the board said it continues to work with partners at the city to encourage organizers to move the event, which used to be held outside the Vancouver Art Gallery.

Cannabis activists have been gathering on April 20 in Vancouver since 1995.

In the years since, what began as a protest of about 200 people has grown to something that resembles a music festival, complete with musical performances and vendors selling merchandise.

And this year's protest may include more underage guests than usual.

Due what officials are calling an unfortunate oversight, students at some Metro Vancouver high schools will have the day off for a professional development day.

A North Vancouver School District principal said the pre-scheduled Pro-D day was not meant to encourage students to attend the event, and that emails were sent to parents suggesting they talk to their children about drug use. Schools in Delta and Coquitlam also have Friday off.

Larsen said vendors are instructed not to sell to minors.

In 2017, St. Paul's Hospital treated 10 patients under the age of 20 in connection with the protest, though no youths had to be admitted.

Vancouver police will be on-hand during the event, and may be dispatching members of its youth squad.

With files from CTV Vancouver's Maria Weisgarber