It was quiet at Webber Park for quite some time after the August 14 pool groundbreaking ceremony. One might have doubted that construction on the natural swimming pool would begin in 2013, but in September the orange and blue lines began to appear on the grass throughout the park. Project signs were erected at either end of the soon-to-be construction zone, and trees that were in the path of destruction - and restoration - were removed. The west end parking lot was closed and demolished, making entering the park building a labyrinthine feat.
The 74-stall parking lot is mostly complete, with installation of rain garden plants and other landscaping around the lot planned for next spring. What seemed like slow progress has made way for full blown construction. MPRB Construction Manager Jon Duesman said that wet autumn conditions and earlier than expected cold temperatures slowed down some of the work. Even so, prior to winter’s snowfall, the three distinct pond areas were emerging as landmarks of the new Webber Park landscape, as a huge mountain of dirt was pulled from the Earth and piled on the footprint of the former pool. If anyone thought that a natural filtration swimming pool was a simple matter of moving water through some aquatic plant matter and back into the swimming area, they were mistaken. Duesman said there are still many miles of below ground piping to be installed and contractors will be working off site, fusing pipes during the winter so they can be installed as soon as possible in this spring.
If you’ve walked or driven by the park, you will notice that below zero temperatures haven’t halted construction. The workers are there Monday through Friday and some Saturdays, regardless of conditions or temperature. According to Duesman, the workers are employing the use of cold weather techniques in order to work as late in the year as possible, so critical project components can be completed. One can see the large plastic shelters that workers have constructed to improve their working environment. The new snow flattens the contours of the ponds, but one can observe changes to the terrain daily.
The water from the Natural Swimming Pond (NSP) will be purified by the movement of the water through filters and the biological workings of plants and microorganisms. Initially the water flows out of the Swimming Zone by gravity and follows a path that takes it through natural fine-filters. These filters remove debris and particulate matter. The force of gravity continues to move the water into the Regeneration Zone, where the water moves through the under lying layers of rooted aquatic plants. A circulation pump will then draw the water out of the Regeneration Zone and return the purified water back to the swimming zone. The regeneration zone is the key to the purification process. In this part of the process undesirable matter in the water becomes nutrients for the microbes and plants in the regeneration zone. There is no soil in the filtration system, which means that the plants and microbes will absorb the organic matter that could otherwise become a problem as algae growth. The water will not be sterile in the sense of a chemically treated pool, where the intention is to kill all organisms, except the swimmer. Ideally, the NSP system clarifies and purifies the water and the biological elements that remain will be balanced in a healthy ratio that is called stability.
Duesman says that the regeneration zone is taking shape, with most of the rough grading and piping having been completed by late November. The concrete footings and foundations for the water tank and fine filter tank have also been poured. Earthworks operation for both the upper and lower swimming pool is also complete. The excavation and installation of concrete footings for the upper pool began in November, with the majority of the footings having been poured. Duesman is hopeful footings for the lower pool will be installed before the end of the year. The pool house construction has started and the building contractor will be working through the winter to build the above ground portions of the building.
As of this writing there has been no change to the grand opening in August 2014. When the ribbon is cut and the public enters, they will enjoy free admission to a 21,000 square ft. pool, which is three times the size of the former swimming pool. In addition the design includes a 4,500 square ft. wading pool, lap lanes, a diving well and a jumping cliff. The new bathhouse will be a multi-use facility, doubling as a warming house for winter skating. The master plan also includes relocation and reuse of historic park benches, bike racks, rain gardens, new lighting, and expansion and reconstruction of the recreational paths. In an update on the Webber Park renovations, Commissioner Jon Olson stated, “It is without a doubt that Webber Park is a key gathering place for the surrounding neighborhoods.” For info/updates check out the project webpage at minneapolisparks. org/default.asp?PageID=1286.