A rooftop water tank on a Manhattan building came off this week, and the removal exposed the wood-cistern construction trade most New Yorkers never think about until a tank has to come down.

The tower sat atop a building that had drawn attention earlier this year as the nesting site of a rare family of barn owls, first reported by CBS News and ABC News. Photos published by both outlets show the tank's roof dismantled and the structure partially disassembled as of this week.

Wood water tanks are built and maintained under New York City's own rules: DOB requires periodic inspection, and tanks over a certain size need a filed permit for both installation and removal, since the structure sits over a public way and carries real weight and water-pressure risk if it fails. The trade is a narrow one in the city — a handful of licensed tank companies, most of them generations-old family shops, build and service nearly every wood tank on the skyline.

Removal work like this gets permitted the same way any rooftop demolition does: a DOB permit, a licensed rigger or contractor of record, and — on an occupied building — a plan for protecting the sidewalk below. For a GC or roofer bidding adjacent rooftop work, a tank removal or reconstruction nearby is worth flagging in a site survey; the crane pick and sidewalk protection for a tank job can affect staging for an unrelated project on the same roof or an adjacent one.

Neither CBS News nor ABC News identified the building's address or ownership, and DOB's public permit search was not checked against a specific address for this item because none was published. The construction activity itself — a tank roof removal — is confirmed by the photos both outlets ran this week.