FWIW, it's steam. Steam (for heating) is delivered by pipe in Manhattan. (In Co-op City, heated or chilled water is similarly centrally heated [or chilled] and delivered by the Ric-Well system that was perennially in need of repairs. In the winter [at least before the Greenway became the Asphaltway] the path of the heated-water pipe could be seen from the melted snow.) Dig we must!

It seems that one cannot take a bad picture in NYC! Love the mood...now where's the Jazz soundtrack?