142-year-old Rosenwach Tank makes icons of New York skyline

Up on the roof, 12 stories above W. 86th St., six craftsmen plied a trade from the post-Civil War era, hammering upright cedar planks into place and tightening the lugs on nine galvanized steel hoops that encircled them.

The workers were making a wooden water tank – a relic of old New York that’s a must for even the most modern skyscrapers in a city with naturally low water pressure.

“Paris has the Eiffel Tower, Pisa has the Leaning Tower and New York has the water tower,” said Andy Rosenwach, 55, who  manages the family business, Rosenwach Tank Co.

He’s got an arsenal of quips because he’s the fourth-generation owner of one of only two surviving New York City wooden tank builders.

Because water pressure is low, city buildings more than six stories tall use electric pumps to send water to rooftop tanks. Gravity delivers it to sinks, tubs and toilets as needed.

Rosenwach Tank was recently featured on the popular Discovery Channel series “Dirty Jobs.”

E-mails pour in from water tower groupies – one man sent photos of himself dressed as a wooden tank for Halloween. Strangers see the Rosenwach name painted on his car and tell him, “We love your company.”

It was started on the Lower East Side in 1866 by barrel maker William Dalton. In 1894, he hired Polish immigrant Harris Rosenwach. When Dalton died two years later, his widow Mary sold the employee his “lumber, tools and goodwill” for $55.

More than a century later, wooden water tanks continue as icons of the New York skyline. There are about 10,000 – more than in any other American city.

Some buildings have steel tanks. But many landlords prefer unpainted wood – which insulates the water efficiently and imparts no taste to it, and lasts a long time.

A cedar tank lasts 35 years. In the past, when redwood was available at reasonable prices, tanks lasted even longer. The old tank the crew was replacing on W. 86th St. between Columbus and Amsterdam Aves. had been installed by other Rosenwach workers in 1966.

Wood tanks are cheaper than steel, which must be lined so rust doesn’t seep into the water.

A 10,000-gallon wood tower costs $30,000. A steel tank that size costs up to $120,000 because of the labor – parts are hauled to the roof and welded, which could take two months, Rosenwach said. An old wooden tank can be dismantled and a replacement installed in a day.

Tanks aren’t made of plastic because it doesn’t insulate well against heat and cold; the use of fiberglass is prohibited by the city fire code.

Rosenwach crews build 200 to 300 wooden tanks a year, and top each one with a decorative rosette made of four R-shaped pieces of wood to mark them as their handiwork. The planks are prepped at a company wood mill in a former stable in Williamsburg, Brooklyn, using machines from the 1930s.

BY LORE CROGHAN

Daily News