Vessel 1 attempted to pull into Slip G2 on the west side of the channel between F and G Dock at North Point Marina.  Vessel 1 came too close to the boat  in Slip G1 and reversed throttle back into channel to avoid collision.  Vessel 1 throttled forward to cease forward movement.  Operator of Vessel 1 slipped and inadvertently bumped throttle forward too far causing the vessel to accelerate rapidly under walkway.  Vessel 1''s windshield was sheared off by walkway and it struck the rocks at north end of channel becomming grounded and wedged under the walkway.  EMS was called to scene and operator was determined to be uninjured except for minor scrapes and lacerations.  He did not receive medical treatment.
Winthrop Harbor               