The Oct. 18 sinking of the 65-foot vessel was traced to the failure of two hoses to drain water from a rear storage compartment, park service spokeswoman Christie Vanover said.
One hose was disabled by a kink, and the other wasn’t properly connected, Vanover said.
No one was on the boat and no one was injured when the 1996 Skipperliner, named Rendezvous, became swamped and sank stern-first in 49 feet of water in a slip at the Temple Bar marina on the Arizona side of the Colorado River reservoir.
The vessel and items in it were a complete loss, the park service report said.
Newton’s sister-in-law and family spokeswoman, Tricia McCrone, didn’t immediately respond Thursday to messages. McCrone had said that Newton and his wife, Kathleen McCrone, were vacationing out of the country when the boat sank.
The vessel was one of the largest on the vast reservoir behind Hoover Dam. A photo provided by the Park Service at the time showed the boat’s bow sticking straight up from the water.
The loss of Newton’s yacht came several weeks after the 71-year-old “Danke Schoen” crooner lost a three-year ownership battle for his 40-acre “Casa de Shenandoah” estate. Newton had lived at the spread several miles southeast of the Las Vegas Strip since 1968.
Newton had creditors at the door when he sold the property in 2010 for $19.5 million to CSD LLC, headed by investors Lacy and Dorothy Harber.
Newton, his family and their menagerie of exotic animals moved in June to a downsized nearby property with several homes on about 20 acres.
His former estate was put up for sale in September for $70 million.