Norfolk Southern officials said Tuesday that culverts in Flowery Branch were overwhelmed Sunday by the heavy rains that fell overnight. Rick Harris, director of corporate communications for the railroad, said flooding was not about culvert failure, rather it was the amount of rain that fell in such a short time that overwhelmed everyone’s culvert systems, including the railroad’s, which were recently fortified. Those culverts include one under Flowery Branch Creek, near Park Drive and west of the tracks, and two at an unnamed stream about 900 feet south of Flowery Branch Creek, he said.