This little shack contains a valve chamber for a city water supply tunnel running hundreds of feet beneath the surface, bringing in water from the Catskill Mountains.
Like the Bedford-Atlantic Armory, this facility is currently being used as a homeless shelter.
From Dusk of Dawn:
"We are the supermen who sit idly by and laugh and look at civilization. We, who frankly want the bodies of our mates and conjure no blush to our bronze cheeks when we own it. We, who exalt the Lynched above the Lyncher, and the Worker above the Owner, and the Crucified above Imperial Rome."