On July 24, the Minneapolis Parks & Recreation Dept. opened the United States’ first public natural swimming pool through Labor Day. Somewhat popular in Europe, natural swimming pools have started to break into the America market in the past few years.

These pools forgo the use of chemicals through a filtration system containing aquatic plants like those used in koi ponds, combined with skimmers and pumps.

The Webber Park pool was supposed to open last summer, but has faced problems and controversy since design and construction began in 2012. The original robotic cleaners broke down and were unable to clean the pool properly.

“We [have] a zero depth entry. The little robot [cleaners] didn’t quite get it,” said Jon Olson, the Minneapolis Parks & Rec District 2 Commissioner. “[They] would just keep going up the ramp and into the grass. They were trying to clean the grass not the pool.”

The department had to purchase new, custom- made cleaners from a firm in Europe.

The project also went over budget. It was slated to cost around $4 million, but the price jumped to over $6 million.

Olson defended the rising cost: “... If you’re looking at it in 2005 dollars, it’s a $4 million dollar project.”

He said concrete costs rose sharply due to demand from construction of the U.S. Bank Stadium for the Minnesota Vikings.

The project was 10 years in the making and replaces a crumbling pool built in the ‘50s. Officials worked with BioNova Natural Pools.

CEO James Robyn said the firm would continue to consult with the city after the pool opens.

Minneapolis Parks & Rec Superintendent Jayne Miller was enthusiastic about the opening. “This is exciting, and it’s been challenging,” she said. “When you do something new and innovative, you plan as much as you can.”

For now, the opening will be a chance to test the pool’s capabilities, with some limitations due to the delays caused by the broken vacuums. Currently, the staff hand-vacuums the pool, which takes a few days.