RedactedNarrative: On July 23, 2013 at approximately 1300 hours, Operator was operating her vessel on Lake Tahoe in the area of Logan Shoals.  She was towing her son on a wakeboard.  Her son''s friend was in the vessel and the observer.  There are three "Danger Shoreward" buoys at Logan Shoals arranged north to south stretching about 1/3 of a mile marking the shoals.  She was northbound approximately 250 yards from shore and 100 yards inside the "Danger Shoreward" buoys.  She was traveling approximately 25 MPH.  She told me she saw a rock sticking out of the water about 6" and turned slightly right to avoind it.  She did not see a submerged rock about 100''  southeast of the visible rock.  The outdrive of her vessel struck the submerged rock.  She shut the engine off realized the vessel was taking on water.  She called 911 and Vessel Assist.
  
  I arrived about 1310 hours.  Vessel Assist was already there and had the three occupants onboard their vessel.  I brought the three people onboard my vessel.  Vessel Assist towed the disabled vessel to the Cave Rock boat ramp.  Operator told me what had happenned and I confirmed that no one was injured.  At their request, I transported the to the Pinewild condominiums.
  
  At 1500 hours I was in my patrol vehicle and saw the vessel parked.  I took pictures of the damage on the vessel and saw that the outdrive was missing.  On July 24 I contacted Operator who told me the vessel had been taken to Walker Marine in South Lake Tahoe.  I went there and saw the outdrive in the back of a truck and took pictures of the damage to the outdrive.  Personnel at Walker Marine told me they had to take the outdrive off the vessel before they could tow it as the mounting hardware had broken in the accident and it was attached only control cables and hydraulic arms.
  
  Warden took pictures of the submerged rock on July 24th.  He estimated the rock was 12" below the water surface.  The pictures he took clearly show gelcoat and fresh scars on the rock.
  
  In the diagram, the white oblong figure represents the visible rock Operator turned slight right to avoid.  The black oblong figure represents the submerged rock her vessel struck.  When I arrived, I saw the boat was about 25'' southeast of the submerged rock with the bow pointing in approximately the same direction.
NameOfBodyOfWater: Lake Tahoe
NearestCityTown: Glenbrook