Psst! Don't tell anyone, but the annual street party in the Castro the Saturday night before Pride will be from 7 p.m. to midnight. But, seriously, mums the word.

So is the message being sent out by the Sisters of Perpetual Indulgence, who have organized the "spontaneous" street event since 1998 as a fundraiser for local LGBT groups. This year the Sisters are trying to keep the very existence of what is known as Pink Saturday a secret.

The silence is due to concerns that the same security and safety problems that caused the city to cancel Halloween in the Castro this October 31 could very well spell the end of the beloved Pride weekend tradition.

Along with Mayor Gavin Newsom and District 8 Supervisor Bevan Dufty, the Sisters sent out a request late Friday, June 15 for a "media blackout" about this year's event. According to a letter signed by Newsom, the party is a "permitted non-event" and it is explicitly stated in the permit that the event is not to be advertised or promoted in any way.

"This has been the longtime agreement between the Sisters and the city, and speaks to everyone's interest in helping to insure that the event and the number of attendees will be kept to a manageable and safe size," Newsom writes in his letter. "To avoid having a situation that resembles Halloween in the Castro, the Sisters are firmly requesting a media black-out on the Pink Saturday street party until after the event has concluded at midnight on Saturday June 23, 2007."

The Sisters have removed any mention of this year's party from their Web site, though it does state proposals for Pink Saturday grants are due July 2. Last month the drag nun group asked Pride organizers to do the same. Pride had posted information about the event under the frequently asked questions section of its Web site.

The Sisters also approached radio station Energy 92.7 FM to request that they not advertise the party or broadcast live from the event this year.

Earlier this month the Sisters asked the Bay Area Reporter not to publish any stories about the event until after it had occurred and declined to discuss the beefed up security at this year's event for this article.

In an e-mail, Sister Barbi Mitzvah said the worry is a story might draw more attention to the event should it be published prior to the actual day.

"Concerns are that a copy of it could find its way to people outside the community or on the Web and entice people to 'challenge' our new procedures or invite unwanted activity to happen," wrote Mitzvah. "As stated with all the concerns with Halloween, we are trying to keep this to 'our hood' and keep out mass crowds that could incite gang members, thugs or just plain massive crowds which our volunteer organization is unable to accommodate."

The same strategy had been deployed for the Halloween party, which the Sisters used to oversee but stopped producing due to the ever-increasing size of the crowds. In the vacuum of leadership Castro merchants stepped in, and tried without success, to keep the media, and in particular, television news trucks, from covering the event.

The cameras showed up anyway, and reporters did live reports from the heart of the gay neighborhood. Without any spokespeople controlling the messaging, the news reports turned into Bay Area-wide invitations. It wasn't until the mayhem of Halloween 2002, when several people were stabbed, that city officials began to reign in the party.

Whether the "no news" strategy will work for Pink Saturday remains to be seen.

Television station KTVU Channel 2 aired reports about the media blackout Monday and Tuesday of this week.

"I might have handled it a little differently but I believe in the underlining premise," said Castro merchant Patrick Batt, who tried not to have the media cover Halloween when he served as president of the neighborhood's merchant group. "As a result of that kind of media attention to what was a wink-wink, nod-nod unofficial streets closed event, we are inviting people in who don't want it to be a ... fun event and that is a problem."

Dufty said this week he did not know about the mayor's letter and that he did not see a problem talking to community papers about the event. But he did agree with requests that there not be live TV reports from the Castro Saturday night.

"I didn't participate in media strategizing on this," said Dufty, adding that, "I don't want media doing live shoots. It is not good for this event."

Despite their not wanting to talk to the media, Mitzvah did publish a page-long write-up about this year's Pink Saturday in the Merchants of Upper Market and Castro June newsletter, and three Sisters spoke at the merchant group's June meeting earlier this month about the new security measures being put into place to ensure a safe event.

"We've really upped our security this year," Mitzvah said at the meeting. "We are not advertising the event so as not to bring in hoodlums."

At the meeting, merchants expressed concerns that the Pink Saturday party is becoming unmanageable.

"This is very much on the verge of our losing control of this event because of the underage drinking," said Batt.

Police Officer Lisa Frazer, who patrols the Castro and has worked with the Sisters on planning for this year's event, expressed the same concerns.

"We are at the verge of losing it like Halloween. We do want it to be a safe event," she said. "I think our community knows how to party responsibly. It's outsiders who screw it up."

With the new procedures in place, the Sisters are hopeful the event will remain a fun and safe event.

"I recognize people's concerns that it not turn into chaos. We are working very hard to keep it our event," Sister Gladys Pantz Arhoff told the merchants.

The Sisters have been meeting for the last several months with merchants, resident groups, entertainment commissioners, police officers, and city staff to plan for the street party. This year inside the gated area of the event – from Castro and Market Streets along Castro to 19th Street and on 18th Street between Hartford and Collingwood – paid Special Patrol officers will be policing the crowd.

Castro Community on Patrol volunteers will patrol the residential areas outside the event. The paid and volunteer patrols will be in radio contact with a central command post at the Eureka Valley Recreation Center. The police intend to have a significant presence at the event, and security staff will be stationed at the main gate at the Castro and Market Street intersections.

The event will remain "wet," meaning alcohol will be allowed but only if it is in plastic containers. All cans or glass bottles will be confiscated.

Also, inspectors from the state Bureau of Alcoholic Beverage Control and the police department's vice squad will be on site to "curb illegal and dangerous drinking and sales," according to the Sisters.

According to the Sisters, attendance at the event ranges between 35,000 to 40,000 people. Every Sister plus more than 300 volunteers from local organizations work the event, which costs "tens of thousands of dollars" to produce.

"Our costs have gone up 50 percent," Mitzvah said at the MUMC meeting. "We felt this year it was the right time to up things because of the fear and crowds over Halloween."

As for keeping it a secret, that seems hardly possible. Pink Saturday has its own Wikipedia entry. A Google search under "Pink Saturday, Castro" brings up 464,000 results.

And the SF Weekly named it "Best Pride Weekend Event" in its Best of San Francisco 2007 awards published in its May 16 issue.

According to the alternative newsweekly, "Pink Saturday is a most special time during Pride Weekend for those of us true homosexuals who know that being queer isn't about equal rights, same-sex marriage, or gay adoption, but instead about drinking, drugging, dancing, and pissing on the street corners with your pals."

"Happening the day before the fascinatingly lame and clearly castrated Pride Parade, and just after the swell Dyke March, Pink Saturday holds all of the party magic of Castro Halloween nights of yore minus the costumes, gay bashing, and heterosexual gawking. It's the one night of the year when local and bridge-and-tunnel gays of every ilk come together in harmony to party like frat boys," concluded the paper's editors.

Just, for the Sisters' sake, don't tell anyone else.