VESSEL 1 WAS FISHING IN THE TAILRACE OF BIG BEND DAM IN LYMAN COUNTY, SOUTH DAKOTA.  AFTER FINISHING A DRIFT O/O1 BEGAN DRIVING HIS BOAT (SD 281 EH) TOWARDS THE DAM TO SET UP FOR ANOTHER DRIFT.  O/O1 ALLOWED ONE OF HIS PASSENGERS TO REMAIN SEATED IN THE FORWARD FISHING SEAT, PARTIALLY BLOCKING THE OPERATOR'S VIEW.  VESSEL 1 WAS TRAVELING EAST/SOUTHEAST NEARLY DIRECTLY IN TO THE SETTING SUN.  O/O1 NEVER BROUGHT THE VESSEL FULLY ON TO PLAIN, BUT KEPT THE BOW HIGH AND KEEPING HIS SPEED DOWN.  

VESSEL 2 WAS ENGAGED IN FISHING ACTIVITY IN THE SAME AREA AND HAD A FOWLED HANDLINE THAT O/O2 WAS ATTEMPTING TO FREE.  O/O1 DID NOT SEE VESSEL 2 (SD 648 CG) AND STRUCK VESSEL 2 ON THE AFT PORT SIDE, CAVING IN THE GUNNEL AND DAMAGING THE ENGINE COWLING.

NO PFD'S WERE USED IN EITHER VESSEL, NO DRUGS OR ALCOHOL HAD BEEN USED BY EITHER O/O
FT THOMPSON                   