PHOENIX - The Burton Barr Library, which houses not only a rare book collection but a vault containing irreplaceable Arizona artifacts, will remain closed until further notice, due to damages caused by a microburst that swept the area Saturday evening.

Building maintenance reported a leak right before 8 p.m. Fire crews responded and found a microburst moved roof tiles, which the roof is designed to do, however, at one point the roof membrane was lifted up and when it slammed back down the impact broke a sprinkler pipe.

That set off the sprinkler system in the library, which firefighters estimate caused about 50 to 60 gallons of water per minute to flow throughout the building.

What was damaged?

As of Sunday afternoon, crews were still assessing damages but estimate at least 50 percent of the building was damaged.

"At this point, we have about 300 drying fans and 30 to 40 dehumidifiers. Now they're working on controlling all the moisture in the building," said Phoenix Fire Captain Reda Bigler.

Phoenix Fire Department shared pictures of the inside of the library. Damp books could be seen littering the floors, computers were covered with plastic.

The Burton Barr Library is also one of very few public libraries to have a rare book room, with more than 5,000 rare items, luckily, that room was barely touched.

Neither was the Arizona Room which hosts many Arizona artifacts.

However, it's unknown how many books the library lost in the incident. Lee Franklin, with Phoenix Public Libraries said the library has very stringent quality standards for their books, and that means those that got wet might have to be taken out of circulation.

How long will the library be closed?

It is not clear how long Burton Barr Library will be closed while crews continue to clean up.

Franklin said any checked out materials can be brought back to any one of Phoenix Public Libraries other 16 locations.

If Burton Barr is the only library you can access, you can call the at 602-262-4636, and they will make arrangements with you.

Meanwhile, you can find any updates to when the library will reopen at