Go jump in a lake - in your own back yard!
By Jean-Marc Daigle

One of the things I most cherish is a long, refreshing swim on a hot summer day in a cool, clear lake, and then hanging out on a warm slab of shoreline rock to dry off and soak it all in.

Water was a big part of my youth and to this day, I still look forward when I can get myself north to a beach or a lake.

I always end up wishing for a jump in a lake.

If you are like me, you might be interested to know that there is now a natural, e c o l o g i c a l l y - f r i e n d l y alternative to the conventional chlorinated (or salt-water) pool. They are called natural swimming pools, they are all the rage in Europe and Great Britain (where thousands have been built), and they are now bubbling up here, in Ontario.

Conventional pools rely on chlorine and other chemicals sterilizers to keep the water clear and clean and devoid of any life form (other than swimmers). Natural swimming pools are anything but sterile, in that they are designed to promote aquatic life rather than eliminate it. Water quality is maintained through the combination of bio-filters, UV filters, mechanical aeration, and aquatic plant filters that are incorporated into the design. Dollar wise, they generally cost about the same as a conventional pool.

Although many different styles and designs are possible - including more formal layouts - natural swimming pools typically look like a natural pond. They usually include lots of aquatic plants, a waterfall and/or creek, and natural stone at and below the water line.

The pool basin must be carefully sculpted with a wide perimeter shelf and a central deep zone, and then lined with a durable heavyduty EPDM or PVC liner. The key feature of the natural swimming pool is a submerged retaining wall that keeps the granite rockfilled plant filters on the perimeter shelf separate from the open swim zone.

Natural swimming pools rely on external, highefficiency pumps to circulate the water through the plant filters, waterfalls and other filtration devices. Once the algae-fighting bacteria and plant filters are established, they do a great job of keeping the water crystal clear and fresh, while the UV filters ensure that ecoli bacteria is kept in check. The design can also include a diving dock or rock slab, steps, underwater lighting and other accessories.

Yes, there are "bugs" in the system - literally. Within a few days of filling a natural swimming pool, water boatmen and water striders will make an appearance, along with a coterie of other harmless - and in fact beneficial - creatures, such as butterflies, dragonflies, frogs, newts and songbirds that prefer wet environments. This, in fact, is the beauty of natural swimming pools: not only are they are great to swim in and beautiful in all seasons, they also create wonderfully diverse aquatic habitat teeming with life.

No, natural swimming pools are not to everyone's taste: some may be squeamish about swimming next to plants and other creatures. Nor are they suited to every site: they generally require more space than a conventional pool to accommodate the plant filters, so they are better suited to larger properties (though pools can be sized for smaller lots). But, for the right homeowner on the right property, natural swimming pools can be a beautiful, refreshing, ecologically sensible alternative to the conventional pool, and they can certainly help satisfy that urge to "go jump in a lake"! Jean-Marc Daigle is a landscape architect, builder, author, and president of Genus Loci Ecological Landscapes Inc. Genus Loci specializes in ecological landscaping, which works with, rather than against, nature to create sustainable gardens and landscapes that are beautiful, functional and e n v i r o n m e n t a l l y responsible. Jean-Marc can be reached at 905-939- 8498, or jmd@ecologicaloutlook.ca.