CORVALLIS — Oregon State University’s Greek houses have largely abandoned their annual Mother’s Day weekend at Lake Shasta in the three years since a student committed suicide there.

Before the death of 23-year-old Gina Zalunardo, three or four dozen houseboats filled with Oregon State students would be on the lake in Northern California for the Mother’s Day weekend. At the start of this weekend, however, only five boats had Oregon State students.

“It was huge. Huge. Every chapter had five or six boats. They got T-shirts printed for Shasta,” said Ron Thiesen, who ran Campus Connection, a business that sold sweat shirts and other goods to the Greek community for nearly 25 years before closing last year. “It was going well before we opened up the store.”

Shasta County Deputy Gary Van Dyne said the lake now is less popular as a college party locale at Oregon State and other schools.

From 2003 to 2005, there were anywhere from 160 to 220 student-occupied houseboats over the Memorial Day weekend, each with about 25 people. This year, he expected a maximum of 140, including Oregon State students who have largely abandoned the Mother’s Day weekend for the trip and switched to the other holiday.

Van Dyne said the sharp rise in gas prices might explain some of the decline.

But Greek leaders openly advocated against Shasta after the death of Zalunardo, a member of the Delta Gamma sorority who hanged herself following an argument with a boyfriend.

Zalunardo, who had a blood-alcohol content of 0.14 percent, wasn’t the first tragedy at Shasta for OSU. In 2001, Sigma Phi Epsilon fraternity member Sean Matsuda, 19, drowned when he slipped and fell from a houseboat. In 1992, 19-year-old Stacy Epping was swimming when a houseboat backed over her. She was caught in the propellers and her left leg had to be amputated. In 2005, University of Oregon student Joel Meyer drowned during Memorial Day weekend.

“When you really think about it, it’s a terrible idea to involve booze and water. Unfortunately, it took a tragedy to make people realize how real the danger was,” said Trevor Giroux, president of the OSU Interfraternity Council, who went to Shasta three years ago as a freshman, when it was hyped as a good way to blow off steam.

Sigma Phi Epsilon stopped going to Shasta the year after Matsuda’s death.