Buttermilk Channel

Buttermilk Channel is a small tidal strait in Upper New York Bay in New York City, approximately 1 mile long and 0.25 miles wide, separating Governors Island from Brooklyn. The channel is marked by a number of navigation aids . Tidal currents on the channel are rather strong.
Origins of the name are uncertain but it is alleged to be a reference to the dairy farmers who used to cross this channel by boat to sell their milk in Manhattan markets. Some people believe that the channel got its name because crossing it was so rough that the farmers' milk was churned into butter by the time they reached Manhattan. According to another legend, before the channel was dredged to accommodate cargo ships, cows were walked across it at low tide to graze on Governors Island. In his newspaper articles about Brooklyn history, Walt Whitman wrote of a time "as late as the Revolutionary War cattle were driven across from Brooklyn, over what is now Buttermilk Channel, to Governor's Island." In the bitter volcanic winter of 1817— the volcanic winter following the "Year Without a Summer"— when the thermometer dropped to −26 °F , the waters of the Upper Bay froze so hard that horse-drawn sleighs were driven across Buttermilk Channel to Governors Island.

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