A north Minneapolis community swimming pool touted as an unusual ecological experiment has run into numerous delays and cost overruns, leaving area residents without a public pool as midsummer heat approaches.

The new pool was supposed to open at Webber Park in 2013, but now is not slated to open until at least the middle of July. When it does start welcoming guests, the $7 million price tag will have nearly doubled from the 2012 estimate of $4 million.

“I’m shocked by what it’s costing,” said former Commissioner Bob Fine, who was on the Minneapolis Park and Recreation Board when the pool was approved.

Park officials plan to announce an opening date for Webber on Friday.

Supporters heralded the pool as the first in North America to use simulated wetlands, rather than chemicals, to cleanse water. But then came rain delays, inadequate robotic pool vacuums, unexpected obstacles underground, toad migration and even duck droppings that delayed the opening.

With demolition, extra inspections and testing, consultants and a bathhouse, the project now is estimated to cost $7.2 million. That includes $140,000 for three specialized vacuums to clean the pool floor, replacing three earlier ones that cost $18,000 and did not do the job.

“The vacuum is really critical to the operation of that pool,” said Cliff Swenson, director of design and project management for the park system. Without a nightly vacuuming, the pool bottom would get a slippery feel like rocks in a river, he said.

Webber-Camden residents opted for the natural filtration pool, which uses an adjacent bioengineered pond to cleanse water like a wetland, after the previous outdoor pool closed in 2010.

“People wanted something different and innovative and that’s not without its challenges,” said City Council President Barbara Johnson, who represents the area. “It would have been much easier to replace the pool with a standard pool.”

The park district sent four staffers to Europe to examine some of many public natural filtration pools in use there before breaking ground in 2013. But initial excitement has given way to some apprehension about the pool.

“I’m very frustrated with the cost overruns and the timetable on this thing,” Commissioner John Erwin said.

Swenson said park officials are determined to get things right before opening the pool. “We’re doing the best we can to get a good facility,” he said. “If we make a mistake, we’re going to be pointed at, ‘What’s wrong with you?’ ”

Another complication arose when area ducks flocked to the cleansing pond. Their droppings had the potential to upset the biological cleansing properties engineered into the pond. So did the unexpected migration of toads, which found the pool and pond a convenient place to spawn.

Park workers collected the amphibians and carried them off, removed their spawn and installed finer mesh fencing to deter new ones from coming back. Cutouts of dogs were used temporarily to try to discourage the mallards, and this year, park officials added lines suspended over the pond bearing Mylar strips.

Swenson said it’s been helpful to have those problems arise now so pool workers are prepared for them.

There were other problems unrelated to ducks and toads. An unanticipated storm sewer manhole was uncovered, as were old light pole bases containing asbestos. More mucky soil than anticipated was discovered, needing to be hauled away and replaced with better fill. A buried dam foundation further complicated work.

The new pool will use a combination of filtration, bacteria and microorganisms that feed on harmful bacteria and aquatic plants that extract nutrients that can degrade water quality. So far, it’s been cleaning the water as designed, Swenson said. That water will more closely resemble the hue of pond water than clear chemically treated pools, he said. A German consultant will give a final inspection next week and then, if given the go-ahead, park officials will set an opening date.

Once it opens, the pool will be free and can handle 500 swimmers at a time.

For now, North Siders are being bused to northeast Minneapolis three days a week to swim at Lupient Water Park while the Webber pool is under construction and the North Commons pool is being fixed. Residents get discount passes.

 

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