I laid out the conceptual design for a natural pool a few years ago, although the client chose not to proceed, partly out of fear of the problems reported in Minnesota. Ongoing, reactive maintenance and planting design are critical components of designing a successful natural pool, as well as a willingness to experiment and maybe not achieve 100% success up front. For example, in our area (southeastern Pennsylvania) geese would definitely pose a problem, but might be mitigated by using tall, dense native grasses in the treatment area and around the pool (geese like clear sight lines). Other creative solutions (dogs, fox dens, fountains) might work in the right context or might create even more problems. To avoid bacterial problems, I suggest "overdesigning" the wetland treatment area of the pool.
In a risk-averse world, my guess is these will remain a niche market, which would be a shame.
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John Zollers EIT,A.M.ASCE
Engineer
AECOM
Philadelphia PA
(215)606-0408
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