The building has been instructed to provide more notice of such things in the future.

Updated 4:30 p.m.

A huge stream of water visible from miles away gushed from the tiered west pyramid facade of One Liberty Place early Sunday morning, soaking the Center City Philadelphia sidewalk below.

Identified later by city officials as part of an ill-prepared fire system test, the liquid continued pouring out for approximately five minutes before coming to an abrupt stop.

Contacted shortly after the flow stopped, a security person at Liberty Place declined to comment on what might have caused the incident at the taller of a dual-tower skyscraper at the heart of the city.

Turns out the gusher was a test of the building’s fire protection systems, which must be certified annually, according to Kathy Matheson, spokesperson for the Philadelphia Fire Department. And while some structures have internal drains to prevent the water from flooding the below sidewalk, this one did not, she said.

“Newer buildings are equipped with special drainage systems that pull off most of the water that is generated by such tests,” Matheson wrote in an email. “Liberty 1 wasn’t required to have this [because] of when it was built.”

One Liberty Place was completed in 1987, when it became the first skyscraper in the city to surpass the height of William Penn atop Philadelphia City Hall.

The annual fire system certification requirement is not new, said Karen Guss, spokesperson for the city’s Department of Licenses and Inspections, which sent inspectors to the site on Sunday

Officials acknowledged building management should have taken more precaution to avoid putting cars and pedestrians in the way of an unexpected shower.

“The certification company and Liberty 1 have been directed to get a street closure permit and police assistance going forward,” Matheson said.

Meanwhile, Philly Twitter had plenty of ideas as to what could have caused the unusual spurt.