I hate to say, "I told you so," ... and I won't, because it's too early and there is no conclusive or scientific evidence yet, but this journalistic report  from The Catholic University of America by "Inside Higher Ed" shows that the new single-sex dorms at the school haven't had much effect on either binge drinking or "hooking up."
In June, when CUA President John Garvey announced the decision to revert to single-gender dorms after being co-ed for years, I argued  that while his stated intention was to lower the incidence of drinking and sexual activity, there was little evidence his move would accomplish much. Instead, I believe, it was most likely a decision meant to satisfy parents and church leaders, primarily conservative ones.
The "Insider Higher Ed" reporter estimates that the student body is mixed, with about half approving of the change and half upset about it. Spray-painted graffiti depicting a man and a woman with the slogan “Life is Co-Ed” has appeared on several places on campus. A planned student referendum on the subject, which will not be binding on the university, will reveal more accurately student opinion.
More interesting would be data that show that Garvey's move was well received by his true audience. Perhaps evidence of increased donations from conservative Catholics?