Every day, Ian McKay calls his friend Rose Pomerleau and leaves her a voicemail.

“English Channel, here I come,” he says.

McKay, 31, has spent three years training for one of the most challenging marathon swims in the world. On Thursday, he will finally set out for England to make his attempt during the first week of July.

McKay has autism, but his diagnosis has been just one factor of many for his team to consider.

Fewer than 2,000 swimmers have completed solo crossings of the English Channel since 1875. The Channel Swimming Association formed in 1927 to authenticate these swims and verify their times.

To be official, a swimmer must be accompanied by a pilot boat to guide the journey and an observer from the association. The expedition can cost thousands of dollars. The pilots give McKay and other hopefuls a weeklong window of opportunity and decide which day is best for the attempt and whether to end it if conditions become unsafe.

Swimmers contend with frigid waters (no wetsuits allowed), jellyfish and winds that can cause waves greater than 6 feet. The Channel is also one of the busiest shipping lanes in the world, active with tankers and ferries. The shortest distance across is 21 miles, but tides often force swimmers to travel much farther.

Still, the people who have watched McKay prepare and given him guidance along the way have expressed complete confidence in his ability to reach his goal.

“He’s really the most determined person I’ve ever met,” Pomerleau said.

On Sunday, a small group gathered at Willard Beach in South Portland to watch McKay swim his last training session before they leave for the Channel. Pomerleau was there, wearing a white cap that said “Ian’s Channel Swim.” McKay’s mom, Shirley Haynes, helped her son adjust his yellow swim cap and fasten a neon orange swim buoy to his waist. McKay waded around children playing in the surf and flashed a thumbs up before he began his laps from one end of the beach to the other. His coach, Will York, paced the sand, tracking McKay in the water.

These three people will be on the pilot boat that will guide McKay from one shore to the next. They are a protective and supportive circle, and they’ve been preparing for years to be a part of this effort. McKay and his mother did not join interviews in order to stay focused on the upcoming swim, but their friends talked about the hard work that brought McKay to this point in his dream.

Pomerleau met McKay when he was 4 years old. She was his first home-based teacher and helped him transition to public schools. He loved the ocean, she said, but he was scared of swimming pools because he couldn’t touch the bottom. Pomerleau was a lifeguard at the time, and she worked with him to overcome that fear. Swimming became an important part of his life, and he frequented the pools at the South Portland Community Center and the YMCA of Southern Maine in Portland. As an adult, he has repeatedly completed Peaks to Portland, a 2.4-mile swim in Casco Bay.

Pomerleau, 59, has stayed close with McKay and his mom over the years. When he swims Peaks to Portland, she always brings him a doughnut at East End Beach. When she signed up for her first ocean swim – part of the Tri for a Cure in South Portland – she joined McKay during his training sessions at Willard Beach.

He never let her skip out early just because she was getting tired.

“He’s way more dedicated than I am,” she said with a laugh. “He was great for me. It was a wonderful, full-circle moment.”

Yes, McKay has been her student in the past, but Pomerleau is joining his effort as a friend. She said his autism might increase the challenge ahead in some ways – the long flight especially might make him feel anxious – but she thinks his desire to get into the Channel will be stronger.

“He is so motivated by this goal that he will rise above that,” she said.

A few years ago, McKay’s mother called Pomerleau and said, “You won’t believe what Ian wants to do.” He had just met Pat Gallant-Charette, a seasoned marathon swimmer from Westbrook who at 66 became the oldest woman to swim the English Channel in June 2017. During their first conversation, Gallant-Charette said, McKay was clearly excited to talk about their shared sport and told her over and over how much he loves swimming.

After they met, McKay decided he wanted to swim the English Channel, too. When his mom reached out to Gallant-Charette for advice, she happily gave them tips about what to eat in the water and how to build up his training. She has been particularly impressed with his dedication to acclimatizing to the cold water.

“I would put Ian right up there with some of the most passionate swimmers I’ve ever met,” Gallant-Charette, 71, said.

York, 31, grew up in South Portland and went to elementary school with McKay. Now, he works as a behavior specialist in Scarborough schools and coaches swimmers from Gorham High School and the Westbrook Seals, a youth swimming club. Pomerleau now works as a special education teacher in Scarborough, and she reconnected the two former classmates when McKay decided he wanted to make the channel attempt. York has been helping him train since 2020.

“I’ve had some really great athletes over the years, but the thing that is so exciting about Ian is he’s not getting out until someone tells him he has to get out,” York said. “The ocean is rough, the ocean is cold, and he gets in and he’s settled. He’s swimming until we tell him to get out. It’s a uniqueness to his spirit, his courage, his effort, that makes him who he is.”

McKay has been through an intense training routine.

One of the greatest challenges for Channel swimmers is hypothermia, so acclimatizing to the cold has been a central goal. The water temperature in the English Channel is generally 59 degrees Fahrenheit at the end of June and increases to around 65 degrees Fahrenheit by September – similar to the water temperature off the coast of Maine – but wetsuits are not allowed because they provide extra buoyancy. McKay practiced without one until October last year and began again in May this year. He and his mom sat outside in winter wearing just T-shirts and shorts. He takes cold showers every day. His mother and his coach have learned how to recognize the early signs of hypothermia and how to tell if McKay is getting drowsy or disoriented.

“I think I could count Ian’s stroke in my sleep at this point,” York said.

“For Ian, it’s hard for him to vocalize how he’s feeling and how he’s doing,” he added. “We’ve trained for years now to know those signs, know those points, know how to talk about those things. And he’s ready. He can be in the ocean for hours and not be cold.”

York remembered a training day at Willard Beach this spring when a group came down to do a cold-water plunge. They raced into and then out of the water in triumph, and then they noticed McKay, without a wetsuit, swimming a steady path from one end of the beach to the other. They asked his mother and York how long he had been swimming (an hour and 15 minutes) and how much longer he would be in the water (45 minutes).

“I didn’t mean to burst their bubble,” York said with a laugh. “But we burst their bubble so bad.”

McKay has started to scale back his training so he can save energy for the big day, like a marathon runner tapers to shorter distances before a race. He swam 50 minutes (about 2 miles) on Sunday, but he had been swimming two to four hours every day during his training. He had to swim at least six hours even to qualify, and York estimated it will take him 14 to 16 hours to cross the Channel.

During training sessions earlier in the process, sometimes his mom or his coach would paddle alongside him in a kayak. They’ve practiced his hourly feeds; they cannot have physical contact with McKay during the channel swim, but they can toss him a water bottle with liquid calories (such as mashed bananas). He’ll trail a buoy and lights on his crossing to make sure he is visible in the water. If the pilot cuts the swim short, McKay might get a second chance during his window. He also could attempt the swim again in future years.

“Even before he starts the swim, he’s a champion in so many ways,” Gallant-Charette said. “Training is grueling. He has done it. He has done everything possible to be successful – and now, when he gets to England, Mother Nature will rule the day. If he has good conditions, he’ll make it.”

Beyond swimming, McKay loves baseball and other sports. He likes to listen to the Red Sox on the radio and check out books from his local library. He lives in an independent living community for adults with disabilities run by Specialized Housing of Maine and spends a lot of time with his mom. (“A super mom,” York called Haynes. “Just remarkable,” Gallant-Charette said about her.)

During his training swim on Sunday, he would pause now and then to look for his mother on the beach to give her a reassuring thumbs up.

As their departure date approached, McKay called Pomerleau to leave his daily voicemail. His message was simple but determined.

“I just want to swim for the rest of my life,” he said.