CHULA VISTA — This city has a challenge for its young residents: Trade in your soda for a good soaking.

It's rewarding children who forgo high-calorie, high-sugar drinks for two weeks with tickets to the Knott's Soak City while supplies last.

The goal is to fight childhood obesity, according to a city announcement issued Tuesday.

"We are facing a very real health problem," said Buck Martin, director of Chula Vista's recreation department. "We can be a part of the solution, particularly if we can influence children to make healthy choices about what they eat and drink."

The program promotes drinking water and milk instead of soda, though juice and sports drinks are allowed. The youngsters also will be encouraged to eat fruits and vegetables daily.

To participate, children can register at any of the city's 13 recreation and aquatic centers. A limited number of tickets are available so they are encouraged to enroll as soon as possible.

The Chula Vista Elementary School District recently evaluated the weight of its 24,000 students, of which 68 percent are Latino, and the results were alarming:

A total of 22.2 percent were obese and an additional 17.6 percent were overweight.

What's more, 29.7 percent of the kindergarteners were already overweight, the announcement said.

Experts agree that a major culprit is the over-consumption of sodas.

"We drink soda like water. But unlike water, soda serves up a whopping 17 teaspoons of sugar in every 20-ounce serving," said Dr. Harold Goldstein, of the California Center for Public Health Advocacy, in the announcement.

According to a center study, 41 percent of children ages 2 to 11 and 62 percent of teens drink soda daily.

More information about the "Soda Free Challenge, as well as the location of the Chula Vista's recreation centers is found at www.chulavistaca.gov/rec.

Alexandra.mendoza@sandiegored.com