Iron gates and student keycards help keep intruders out of Harvard buildings, but last weekend's torrential rain was unstoppable.

Although the University faired the storm--which dumped some seven inches on Cambridge in three days--without major damage, flooding affected many buildings and clean-up efforts continue.

"Almost every building had some form of flooding," said John E. Cady, manager of facilities maintenance.

The worst flooding occurred in Mallinckodt Laboratory, because of its proximity to a construction site. The building had two or three feet of water in some areas of the basement, Cady said.

Harvard's libraries were also affected by the rain.

Two inches of rain covered the D-level of Widener Library and the ground level of Lamont Library, said Susan A. Lee, associate librarian of Harvard College for planning and administration.

"[However] none of it rose to a depth that affected the first shelves of books," Lee said.

"Most of the problems have affected the facilities themselves," Lee said, citing wet carpets, buckling tile floors and dead phone lines as the main concerns.

Recovery efforts in Harvard libraries will take close to a month, and the damage is covered by insurance, Lee said. Officials have yet to estimate the cost of the damage.

Other libraries, such as the Harvard-Yenching Library, were also affected by the downpour.

According to James K.M. Cheng, librarian of Harvard-Yenching Library, toilets in that library's bathrooms overflowed. In parts of Cambridge the sewer and storm drains are not separated--a problem Harvard and Cambridge are currently working to repair.

Ten books were damaged and sent to the freezer in Widener Library, Cheng said. Books with water damage are frozen and then slowly thawed out in a controlled environment.

Cheng said that in all "there was minimal damage to the collection" and that Yenching's rare books were completely unaffected.

"We were lucky that...the response of the Widener administration was very fast," Cheng said.

Lee said early response is crucial to protecting the libraries during adverse weather and said the university is studying its libraries "disaster preparedness."