One year shy of the 40th anniversary of the Mercer Island Half Marathon, the planning and preparation are heavily underway for the March 20 event.

The annual race, which brings thousands of racers to Mercer Island in what many consider to be the kickoff to the spring racing season, has been in the planning stages since, well, the day after last year’s event. At the helm this season is Dawn Naye, who will be chairing the event this year and during the anniversary celebration next year.

“It’s going great,” said Naye weeks before the starting gun was set to blast. She said this year that the event, which is running smoothly, is focusing on the fundraising aspect, specifically the funds that the organization donates to the Washington Colon Cancer Stars, which helps with support, treatment and awareness of colon cancer.

“I think the race has been such a great way to see Mercer Island and support a great cause,” said Naye. “Colon cancer is the only preventable cancer. Naye added they always have been contacted by people with stories about how their families have been touched by colon cancer. They’ve often said how the race has made them more aware and helped them learn about getting screened, said Naye. The race also benefits the Mercer Island Rotary Club Foundation.

So far ahead of the race, Naye said registration numbers are down a little bit, after last year’s record number of participants hit Island streets.

“We don’t know if it is because the weather last year before the race was so nice, and this year it’s been so cold, but we’re down about 26 percent,” she said.

While the race’s marketing strategies to remind people of the event haven’t changed, the race organizers are hoping for a last-minute surge during the weekend of the event.

“Last year we had 500 register the weekend of, which is a ton of people, so hopefully that will happen again,” she said.

The Mercer Island Rotary Run, as it is known to many, includes the half marathon — both a run and a walk, a 10k run, a 5k run and walk, and a kids dash. Other than a slight change to the 10k course, which will keep runners on North Mercer Way this year, Naye said the race is the same as years past. This year will also see the return of tents and vendors in the Community Center parking lot, where the race begins and ends. Also, as in previous years, Naye said local businesses have graciously allowed race participants and visitors to use their parking lots for the day.

“It’s a fun, family environment that’s great for Mercer Island,” she said. “It’s fun to be involved.”

Naye said the race wouldn’t be the success it is every year without the help of the city, fire and police departments on Mercer Island.

“They do so much to make it a great event,” she said. “Everyone always says this is one of the best events they’ve been to.”

Naye said the race also wouldn’t be possible without the many volunteers to turn out to coordinate the events and help the runners through the day. She said they are still looking for volunteers to help this year.

Anyone interested in registering for the race or volunteering can visit mercerislandhalf.com.