The 40-year-old firefighter has spent countless hours week in and week out swimming laps to build endurance, to prepare for a 10- to 12-hour swim across Ontario, all for a good cause.

On August 15, the Toronto native will depart from Niagara-on-the-Lake to swim across Lake Ontario towards Toronto in an effort to raise money as part of Swim for Kids, a fundraiser for the burn unit at the Hospital for Sick Children.

"Having the unfortunate experience with burn victims in my job as a firefighter, has made me aware of the horrific pain and suffering they cause," Chisholm said.

" We are very lucky to have The Hospital for Sick Kids in Toronto to deal with illness of all kinds especially the most painful like burns."

Chisholm said he and his fellow firemen recently had a tour of the hospital to get a sense of what he's raising money for. Chisholm said this is his first fundraising venture.

"When I first started fundraising people asked me about my financial goals," Chisholm said. "Having no experience fundraising, I never expected Swim for Kids to raise almost $17,000 two months before my event."

Chisholm said some of the money came from events such as a cycling ventures initiated by his family and friends. Chisolm's quest is also supported by a few corporate sponsors.

Physically training for the marathon swim has been tough, Chisholm said, but mentally, determination and knowing the money is going towards the hospital motivates him to strive for his best.

For more information, visit www.swimforkids.ca.