was landing at Trout Lake, NWT with the pilot and 2 passengers, carrying a load of moose meat and fish. As the a/c touched down on the water, the a/c apparently landed hard, bounced into the air and came down again, and the right float separated from the a/c. The left float was then driven up into the wing, and the a/c nosed over into the water. One passenger was thrown into the control column, and the other passenger received a strained back. The pilot assisted the passenger with the injured back in exiting the a/c and they were all able to used the separated right float to hold onto, while some residents on shore came to the aid of the pilot and passengers with their boats. The passenger with the injured back was treated in hospital and released. It is not known at this point when the a/c will be salvaged from about 9 feet of water. UPDATE On the approach, the a/c contacted the surface of the water prematurely, bounced and struck a sand bar that extended across the flight path. The right float then separated and the left float was driven up into the wing. The a/c cartwheeled and sank nose first in about six feet of water. The water was calm, as was the wind, and the sky was overcast with moderate rain. The pilot reported that he was using the sand bar as a reference point during the approach, and had planned to pass over it and land on the water. However, he misjudged the approach, struck the water heavily, bounced and skidded across the sand bar. A medevac was arranged for the passenger seated in the rear of the a/c who sustained chest, leg, and back injuries. The pilot and front seat passenger received minor lacerations.