Unit 1 was traveling up the reedy river on Lake Greenwood and collided with unit 2. Unit 2 struck unit 1 on the port side. Neither operator saw the other vessel until after the collision. Unit 1 then towed unit 2 back to public ramp. Upon the collision three subjects were injured. Subject1 aboard unit 1, suffered minor cuts and bruises from the impact of unit 2. She hit the from windshield on her vessel cutting her noise. Subject2 was the boat operator of unit 2 and was ejected from the vessel. He suffered a bloody nose from the impact.  Subject3 was the third subject with injuries. She was a passenger in unit two. She had complaints of lower back pain after the collision. She was not ejected from the vessel. All parties refused medical treatment that evening from Laurens County EMS.