The road was closed in both directions between 47th Street and Brook Avenue at 1:40 a.m., a Suffolk County Water Authority spokesman said. The road was reopened just before noon, officials said.
The main broke in two place within a block of each other, the water authority said. The breaks are believed to have been caused by the frigid temperatures, the water authority said.
The temperature at midnight was 27 degrees, dipping to a low of 25 at 4 a.m., the National Weather Service said.
With Gary Dymski