People march up and down Wertland Street going to house parties during the unofficial back-to-school bash known as "Block Party" near the University of Virginia campus in Charlottesville on Saturday, Aug. 20, 2016. (Jabin Botsford/The Washington Post)

Thousands of University of Virginia students, cups in hand, swarmed across the blacktop as the raucous party reached its peak Saturday night, the crowds stretching a quarter mile down Wertland Street under a near-full August moon.

Dance music blared from open doorways. Broken glass beer bottles crunched underfoot as students spilled off the sidewalks and into the road. By the time the crowd dissipated about 2 a.m., there were arrests for public drunkenness, ambulance calls for unresponsive party-goers limp and shoeless on the grass, and crinkled red plastic cups strewn in the gutters like early autumn leaves.

Block Party — the off-campus, unsanctioned bash that is the unofficial start to the school year for many students — was alive and well this past weekend, despite U-Va. administration efforts to discourage freshmen and athletes from attending following persistent problems with underage drinking, rowdy behavior and sexual assaults.

Although many participated, some said the administration’s push did make a dent, noting that the crowd was significantly smaller and more orderly than last year.

The crackdown comes amid a moment of reflection for U-Va. The prestigious public flagship university has garnered national headlines in recent years as the administration struggles to address its reputation as a party school, including the prevalence of campus sexual assault and the excessive consumption of alcohol.

One year ago, U-Va. volleyball player Haley Lind said she was sexually assaulted by a fellow student athlete in a stranger’s house on Wertland Street during Block Party, an incident that rocked the athletic department and drew fresh scrutiny of the problem on this elite campus.

As a result, the university’s top officials commenced an unprecedented outreach exercise this summer to warn parents and students, particularly incoming freshmen, of the risks that lurk camouflaged in the pulsing Block Party crowd.

On Saturday night, Charlottesville Police Chief Al Thomas was among the 36 officers who patrolled the streets specifically monitoring Block Party.

“The university has been really aggressive this year,” Thomas said, noting that his department had partnered with the administration to redouble the enforcement of alcohol-related offenses this year. “This is the first time many of these students are away from home. We will treat them as young adults, and when you become an adult there are consequences for your actions and poor decisions.”

For example, Thomas said, the officers gave tickets for alcohol violations this year when in the past they had handed out warnings.

The popularity of Block Party, and its resilience in the face of opposition, has flummoxed the administration, said U-Va. Dean of Students Allen Groves. Because the festivities transpire beyond university property and inside private residences — and often includes people from other schools and local residents — it has been difficult for the university to take concrete action.

A woman is arrestedduring Block Party in Charlottesville, Va., on Saturday, Aug. 20, 2016. The university administration discouraged students from going, and police stepped up their presence. (Jabin Botsford/The Washington Post)

Cups and trash are seen in front of houses after Block Party, an off-campus bash at the University of Virginia. Some said this year’s party was “tamer” as a result of university counter-programming. (Jabin Botsford/The Washington Post)

Groves said preparations for this year’s Block Party began three months ago, when he met with local landlords and encouraged the rental property owners to revise their leasing contracts to include provisions that would discourage students from hosting big parties. Groves said the university also distributed flyers warning tenants about their legal liability when serving alcohol to party guests.

The university also organized counter-programming this year, including a concert featuring the popular hip hop artist J. Cole, with free pizza and alcohol-free activities at the campus recreation center.

People listen to music and cheer during a welcome-week concert held at John Paul Jones Arena at the University of Virginia on Saturday, Aug. 20, 2016. The concert, and other events on campus, aimed to counteract the unofficial party known as Block Party. (Jabin Botsford/The Washington Post)

Ellie Atherton, a 19-year-old sophomore who attended the J. Cole performance Saturday night, said the concert provided a welcome distraction from Block Party.

“I think a lot of things happen at Block Party that are really dangerous, especially for freshmen who are inexperienced at the party scene,” Atherton said. “The university really made an effort to make campus safer.”

Groves also acknowledged that Block Party’s surging attendance each fall is partly of the university’s own making. Groves said that for the past decade he helped negotiate an agreement with the university’s fraternity chapters to refrain from hosting parties on the weekend before classes. Block Party arose organically in the vacuum, he said.

In a thinly veiled reference to Lind’s allegations of a sex assault from last year, the school’s athletic department warned athletes to avoid Block Party, and President Teresa Sullivan asked families to speak with their children about the potential hazards of drinking to excess, specifically warning about sexual assault.

“We know that the most dangerous time for sexual assault is the first few weeks of the academic year, the period known as the Red Zone,” Sullivan wrote. “More than 50 percent of all reported sexual assaults on college campuses take place during this period. . . . Please remind your sons and daughters that we do not tolerate any type of sexual misconduct at UVA, and ask them to make safety a top priority — their own safety as well as the safety of their classmates.”

On Saturday, droopy-eyed students in collared shirts staggered down Wertland, including a young man who was unable to stand unassisted and leaned into a female friend like a listing ship taking on water in rough seas. A couple kissed sloppily against a telephone pole amid the crush of partiers, a student lay passed out on the concrete steps in front of a brick residence, another vomited off a porch railing.

Typical sights for Block Party.

For Lind, last year’s Block Party was one of the worst nights of her life. Lind, then in the first days of her sophomore year, attended the party with teammates. She said she blacked out during a party on Wertland after drinking a potent liquor concoction and woke up the next morning unaware that she’d had a sexual encounter with another athlete at the party. That athlete, who also was drinking at the party, has maintained he did nothing wrong, and a university investigation found there wasn’t enough evidence to hold him responsible for any violation of school rules.

The experience continues to haunt Lind.

She said she spent Saturday night at her apartment watching movies, while her friends went out to party.

“It’s an anniversary of a transformation of myself that wasn’t good,” Lind said. “It’s been a year, and I feel like I’m a lot older than I am, and I’ve lost a part of my youth and myself that I’ll never get back.”

Lind said that she now views Block Party as the most dangerous night for students at U-Va. She said she speaks to younger female students about the risks of drinking at such parties, when one can be surrounded by strangers.

“It’s crazy that it’s one night that people are willing to risk their lives over,” Lind said. “It’s one night that can change your whole life. It’s not worth one night of partying to risk your entire career and your entire life.”

Correction: An earlier version of this story attributed a quote to a Block Party attendee who misidentified himself to The Washington Post. The quote has been removed from the story, which has been updated.

Cups, beer kegs and trash are seen in front of houses after Block Party. (Jabin Botsford/The Washington Post)

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