By Mike Dunn

PHILADELPHIA (CBS) — Nearly 2,000 city workers got an unexpected day off today after a burst water pipe forced the closure of their Center City office tower.

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The 18-story One Parkway tower at 1515 Arch Street had to be closed for business because a heater pipe on the fifth floor burst Tuesday evening.

Mayor Nutter says this created a mess. “It flooded the elevators and affected the mechanical systems in the One Parkway building.”

The building is one of the primary city office buildings, and houses the Department of Human Services that oversees cases of children at risk.

Nutter says essential DHS functions are operating at a temporary location.

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“The Department is more than operational,” he says, “and we are not anticipating that any cases would suddenly fall through the cracks, or something like that.”

The building houses 1,900 workers in all, and also include the departments of Commerce, and Parks and Recreation.

The tower was constructed in the 1960s for the former Bell Telephone company. Nutter recalled visiting as a child, when his mother worked there.

There’s no word yet as to whether the building will re-open tomorrow.

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