Tashlich                                               photo by Julie Z. Russo

On the first day of Rosh Hashanah, the Jewish new year,  worshippers go to a lake, river or sea and recite the Tashlich prayers, where sins are symbolically cast into the water (like old leaves), in evocation of the verse, "And You shall cast their sins into the depths of the sea." We leave our old shortcomings behind us thus starting the new year with a clean slate.

Text from http://www.chabad.org