Las Vegas, NV (KTNV) -- National Park Service park rangers and other first responders conducted multiple search and rescues at Lake Mead on Tuesday after a thunderstorm formed over the Boulder Basin.
The storm began around 3:45 p.m. and created 5-foot waves and reports of 8-foot swells.
The Lake Mead Interagency Communication Center received more than 70 distress calls from boaters, 11 of which required rescue.
All of the groups had reportedly made it to land.
A woman in her 30s was rescued around 8 p.m. in the middle of the lake after treading water without a life jacket for more than 3 hours.
She was on a personal watercraft and decided to take her life jacket off to go swimming just before the storm hit. She was rescued, treated and released. Her husband and stepson were rescued earlier in the evening.
The remaining individuals who were rescued were wearing their life jackets.
"Life jackets and first responders saved lives today," said Christie Vanover, park spokesperson. "Visitors did the right thing when the storm came. They put on their life jackets, they moved to shore and they called for help when they needed it."
At least one vessel sank and others had to be towed back to the marina.
Earlier in the day, an unrelated search and rescue was conducted on land at Goldstrike Canyon. A teenage girl was rescued after hiking the trail with very little water. She was transported to an area hospital.