Authorities said a Sea-Doo watercraft and a powerboat collided at about 4:30 p.m. Saturday in the launching area near 250 Puddingstone Drive. Investigators worked into the night trying to piece together what led up to the crash.
Aurora Yeso, 59, Mari-con Yeso, 34, and another woman were pronounced dead at the scene.
The male driver of the boat and two passengers were seriously injured, and a female passenger had minor injuries. They were expected to survive.
Investigators don't know if speed was a factor, but at this point, they say there's no indication alcohol was involved.
The deaths were the first on the lake in years.