Harvard and Cambridge police are tightening security in anticipation of the usual flood of spectators and rowers for this weekend's Head of the Charles Regatta.

The gates of Harvard Yard and the houses will be locked starting at 4 p.m. Saturday. Admittance will be restricted to those with Harvard ID, who may bring one guest each.

Students who wish to host overnight guests must obtain permission from their house office or first-year proctor. Guests must be registered before Saturday.

Finally, all "social gatherings" must be registered with the Freshman Dean's Officer or a house office. Large parties are banned, and keg deliveries to the Houses will not be permitted.

These measures are the result of adverse past experiences, said Dean of Students Archie C. Epps III.

"In the past people have used the College grounds as bathrooms, and people have slept in corridors and the like," Epps said.

Most problems during past Head of the Charles weekends have not involved Harvard students, said Harvard University Police Officer Lawrence S. Murphy.

"Generally the problems occur when individuals from all over the country and the world start roaming around Harvard Square looking for something to do," Murphy said.

University administrators have taken steps to dam the river of students from private schools that has traditionally flowed into Harvard this weekend, Epps said.

"We have written to the headmasters of all of the private schools in the area as well as the deans of colleges to explain to them that we don't have housing for their students and can't accomodate them," Epps said. "We've written a couple hundred letters."

The Metropolitan District Commission is also taking special precau- tions to keep its head above water this weekend.

Harvard and Cambridge police will operate checkpoints around the Square to enforce the ban on public consumption of alcohol.

"We have not seen many alcohol problems with our students but with students who come to the Square from private schools," Epps said.

"The Metropolitan Commission has taken more seriously the public consumption of alcohol during the race, and that has cut down on the number of problems," he said.

Many Harvard students find the stream of tourists to be a stroke of misfortune.

"It's going to be a pain," said Lowell House resident Rudd W. Coffey '97. "I hear Lowell House is the worst place because it's so close to the Square. Apparently people end up puking in the courtyard."

Other students objected to the tide of new regulations.

"The commie pinko pigs are trying to ruin our lives," said Haneen M. Rabie '95. "I'm going to Brown to escape."

"We regret the inconvenience to our students," Epps said. "But experience has taught us that it is wise to take such measures.