RedactedNarrative: At approximately 9:00 PM on 09/03/17, Vessel 2 was unattended and docked in Slip E-60 in DuSable Harbor.  Vessel 1 was heading west in the channel between E and F docks of DuSable Harbor.  A witness stated Vessel 1 had three persons on board; one at the bow, one at the helm, and one at the stern.  Vessel 1 attempted to dock at Slip 59, which is just east of Slip 60.  The witness stated Vessel 1 was traveling at a higher speed than normal when docking.  As Vessel 1 was attempting to turn to dock it missed the entrance to Slip 59.  The witness stated the crew member at the bow of Vessel 1 attempted to yell at the operator, but the music was too loud.  Vessel 1 struck the docked Vessel 2 in the stern and damaging the dinghy attached to the swim deck causing it to be punctured and destroyed.  Due to the force of the impact after being struck, Vessel 2 lunged forward and struck its bow to the front of Slip 60.  The operator of Vessel 1 reversed its boat striking Vessel 2 as it attempted to turn.  Vessel 1 backed down the channel and returned to its slip, Slip 59 at slower rate of speed.