For about five minutes on Sunday, a steady stream of water shot from the crown of One Liberty Place, one of Philadelphia's iconic skyscrapers.
There was no fire, no call for help, no rush of emergency responders; just a steady torrent of water tumbling some 800 feet to Center City streets below.
The spray, which began around 7 a.m., left citizens perplexed. WHYY's Billy Penn tweeted video of the stream while searching for information about what was taking place.
City officials were also unsure when first contacted by NBC10. They too were working to figure out what was happening at the 61-story tower located at 17th and Market streets.
Turns out, One Liberty's property manager was conducting a mandatory annual test of the tower's fire suppression system.
Both the property manager and sprinkler company failed to tell the city, a spokesperson for Philadelphia's Department of Licenses & Inspections said Monday. Inspectors went to the building and confirmed the test with the companies.
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"The certification company and Liberty 1 have been directed to get a street closure permit and police assistance going forward," a statement read in part.
As for the sky-high water spectacle, L&I says it's perfectly normal for a high-rise like One Liberty Place because of the building's age.
Newer buildings are equipped with drainage systems that pull sprinkler water down into the stormwater and sewer system during use, officials said. One Liberty, which was opened in 1987, was not required to have drainage systems installed.