RedactedNarrative: On June 23, 2018 I, Game Warden, was aboard my vessel on patrol at Lake Mead National Recreation Area.  At Approximately 7:29pm, I was notified by National Park Service (NPS) Dispatch about a vessel sinking somewhere in the middle of Boulder Basin, with 4 individuals aboard, whom had jumped into the water and boarded an Good Samaritan (GS) vessel.  NPS also had a vessel on the water currently looking for the vessel.  I contacted my dispatch and started a hasty search of the basin.  
  
       At approximately 7:41pm, I arrived on scene, (36.1186, -114.73599) in Boulder Basin, southeast of Battleship rock.  NPS was already on scene.  I observed a yellow vessel (V1) upside down in the water, almost completely submerged.  V1 had noticeable damage on the propeller and the rudder was completely destroyed.  
  
  Due to the onsetting darkness, we determined V1, being capsized, was a hazard to nighttime navigation.  The NPS Rangers attempted to place glow sticks upon V1.  A call was placed to Towboat USA requesting assistance righting and recovering V1.
  
       I advised that I would have the 4 occupants of V1 transfer onto my vessel.  I brought my vessel alongside V2, had them put on their lifejackets, and assisted them onto my vessel.  I spoke with the both operators to get their accounts of the accident.
  
       At approximately 8:40pm, NPS received another emergency call that they needed to respond to.  I stayed on scene with V1 as it drifted toward shore. At approximately 9:16pm, Towboat USA advised that they would not be able to respond due to weather conditions.  At approximately 9:35pm NPS returned to my location. Due to Towboat USA no being able to assist, NPS stayed with V1 until it drifted to shore, no longer being a hazard in open water.  I cleared the scene and transported operator and his party to Boulder Harbor where he was to meet up with a friend.
  
  
  Conclusion
  
  •     V1 ran aground at some point, causing substantial damage to the propeller and rudder, causing the vessel to have noticeable vibrations.  The grounding also heavily damaged the rudder causing the vessel to lose steering.
  
  •     The tow line was place on the top portion of the vessel (hand rail) on not the bow eye.  The bow eye is designed for high stress and is the desired location to tie off a tow line for long distance towing.  The bow eye is specifically placed lower on the keel and allows the vessel to rise in the water during tow preventing swamping.  The tow line should have been placed on the bow eye during the tow.
  
  •     During tow, V2 should have maintained an adequate speed for the weather conditions.  Winds were strong, approximately15-25mph, and waves were rough, approximately 2'' to 6''.