Rachael DeWitt has gone through extraordinary lengths to help preserve the Skaneateles Lake in upstate New York -- and raise awareness for clean lakes and oceans all across America.

       DeWitt currently lives in Washington, D.C., but she grew up on Skaneateles Lake -- just a 30-minute drive "World News Tonight" anchor David Muir's hometown of Syracuse.

       "This lake really made me who I am, and made me care about ocean conservation and water conservation," said DeWitt, who earned degrees in environmental science and marine biodiversity and now works for the nonprofit Ocean Conservancy.

       She learned how to swim in the lake, was on the Skaneateles High School varsity swim team and always dreamed of swimming the entire length of the lake.

       Nine hours, 16 miles and more than 32,000 swim strokes later, that dream has now become a reality.

       DeWitt trained for what would become the longest swim of her life. She swam about 2 to 4 miles a day.

       But the length of Skaneateles Lake is 16 miles -- 10 more than the most she'd ever done.

       At sunrise, she began her journey, jumping into the lake at the village pier and pushing off the concrete seawall.

       DeWitt stopped about every 30 minutes for water and energy bars from her team of kayakers -- including her mom, Terry.

       Her dad, Bob, followed his daughter's nine-hour swim along with some of her supporters.

       "From the minute I pushed off the north wall at the head of the village, everyone was behind me, and all along the way, I saw people with signs of support cheering up and down on their docks," DeWitt said.

       By the time she got to mile 10, she passed by a kids summer camp, where hundreds of children cheered her on.

       "It really just kept me going the whole time," DeWitt said. "They were so inspiring to me."

       DeWitt completed her goal, and was embraced by her parents. She said she celebrated her accomplishment the same way she trained, "with a lot of carbs" – and a surprise party from her friends and family.

       "I did this swim as a lifelong dream of mine, and also to support water quality and conservation, specifically for the Skaneateles Lake Association," DeWitt said. "I'm just so grateful to everybody who came out and shared this moment with me."