Some 1,400 miles into the trip, Ploetz jumped out of the water Friday to throw out the first pitch in St. Louis.
"To be here and throw the first pitch means a lot," Ploetz said. "There's no words to explain it. I can't explain how much it means to me."
Ploetz, a native of St. Charles, Minn., has suffered through PTSD, and when he got out of the Marines eight years ago, a man named Matthew Mohlke recommended he try going down the Mississippi River. Mohlke did so himself in a canoe in 1999, and wrote a book about the experience.
Initially, Ploetz said he blew the idea off. After struggling, he decided to give it a try, beginning his "Paddle Off the War" mission.
"[It's about] doing something that I can attach myself to," Ploetz said. "That's really what a lot of veterans are missing, they struggle with the everyday things -- not being around another Marine or another veteran or another Army gentleman, solider or seaman, all those things. It's a different life."
Ploetz rises each morning he's on the water around 7:30 and takes breaks roughly every two hours. A 12-hour day follows with a goal of moving down the river 50 miles per day.
His goal is to reach his final destination in Louisiana within 64 days in the canoe, spending other time along the way raising awareness as he did at Busch Stadium on the Fourth of July.
"It doesn't take long to do that, but it's a lot of time to think in your boat by yourself," Ploetz said of moving 50 miles each day. "It kind of opens your mind up to a lot of things, because life is slower on the river. You're only going 5 mph. There's a moment every day I've had an epiphany. When you're going 55 mph down the road, you miss those things."
Ploetz has received support along his journey down the river, meeting people who join him on his route. Mostly, he said, he's learned a lot about life paddling with just his thoughts.
"Life is a journey and it's learning curves and stuff like that," Ploetz said. "If you just sit there and enjoy it, don't plan out your day too much, life goes a lot easier that way. You're not so stressed out, you're not so worried about those things in life and you push on."