EE & COWORKER WERE WASHING A BACKHOE AT WASH RACK. EE LOCKED A WATER CANNON ON TO SPRAY THE BUCKET. COWORKER TOLD EE THAT HE WAS GOING TO WASH OTHER SIDE OF MACHINE. EE TURNED TO MOVE AWAY AND STEPPED INTO THE STREAM OF PRESSURIZED WATER FROM WATER CANNON. WAS HIT IN FACE WITH WATER, KNOCKING OFF SAFETY GLASSES. TREATED AT LOCAL ER: IRRITATED EYE/ANTIBIOTIC EYE DROPS.