A sign at the entrance to the Littauer Library warns students of the waters that closed a portion of the facility. The flood was caused by a broken cap in a water main.

A broken water main caused significant flooding yesterday afternoon to the basement of Littauer Library.

Few books are stored in the basement of the library, which opened in 1939 and contains collections on economics, government, and political science, along with the Environmental Science and Public Policy Archives.

The flooding was caused when a cap in a water line broke, according to Matthew P. Stec, the building manager who was on scene coordinating the clean-up effort.

Stec said yesterday evening that it was too soon to say how much damage had been caused by the flood.

He added that a private mold mitigation company had been called to assist with repairs.

Through the library’s ground level windows, numerous men were visible using shop vacuums to clear standing water off the basement’s carpet.

The basement contains primarily study carrels and lockers. Water was visible dripping onto carrels along the library’s east end, and workers were removing ceiling panels in the area.

—Staff writer Evan H. Jacobs can be reached at ehjacobs@fas.harvard.edu.