The lure of water is undeniable for cottagers and homeowners. Throughout the world, from the French Riviera to Australia's Gold Coast, from Vancouver to Nova Scotia _ and in countless freshwater lakes across Canada _ water attracts development. Because we evolved from the first oxygen-producing stromatolites in our oceans, billions of years ago, a primordial affinity for the water was, perhaps, imprinted on our subconscious. Undeniably, people the world over will pay a great deal to have a home with a view of water.

The opulence of Canada can be breathtaking. To sail across our many lakes is to reveal an astonishing array of impressive homes and cottages, some with seaplanes moored at the edge of their lawns. While many homes are in architectural harmony with the natural beauty of the surroundings, there are ominous signs that some lakes are becoming stressed. Mesotrophy, the grim precursor of eutrophy, that natural aging destiny of all water bodies, is clearly accelerating in many lakes, perhaps stimulated by run-off from lawn-fertilizing operations, or from poorly constructed septic systems.

Patches of the ubiquitous eurasian milfoil are increasingly evident in shallower waters, especially near shorelines. The sheer number of small sailing craft, and indeed the seaplanes themselves, are definite suspects as carriers in the increasing proliferation of many species of weeds in these lakes.

Buildings in sensitive areas need stringent pollution controls. Activities such as lawn fertilizing can threaten the very water quality and scenic ambience which drew homeowners to the location in the first place. It need not be so. We have proven technology to protect, or restore, most of the polluted, or stressed, waterways. The recovery of Lake Erie is encouraging evidence of achievable remediation through nutrient removal at our sewage treatment plants.

The loss of value in real estate from a reduction of water quality can be startling when measured by the Secchi Disk, invented by an Italian physicist to measure water transparency. After the disk is thrown into the water, the readings give an accepted measure of water clarity at various depths. Research work undertaken during a Master's thesis at the University of Maine, indicated that every one metre drop in Secchi Disk transparency could translate to a 10 to 15% drop in waterfront property values. For upscale cottage communities, where properties frequently range from $500,000 to $1 million, the total cost of environmental neglect could run to millions. There have been many examples where the neglect of septic systems or lawn runoff has transformed priceless aquatic assets into expensive real estate liabilities. Try selling your dream cottage after a matted carpet of weeds begins to reach out from your shoreline.

Sampling begins, using a Secchi Disk at Clear Lake in Parry Sound, Ont.

Waterfront homeowners on serviced lots are luckier as nutrient rich sewage is pumped miles away for proper treatment. But even on serviced lots problems may stem from proud gardeners who lavish both fertilizers and herbicides to bring about their perfectly green lawns. Unhappily, aquatic plants also respond to lawn fertilizer and herbicide run-off which has serious consequences to fish and wildlife.

For the majority of cottagers who are located on unserviced lots, a great deal of waterfront protection can be achieved simply by maintaining and upgrading septic systems and by maintaining natural vegetation between the cottage and the lakeshore.

Recent research indicates that sophisticated septic systems could achieve a very high order of pollution removal which could match or exceed the treatment effectiveness of a municipal facility. While this is encouraging for the future, regular removal of septage from tanks is recommended and regular maintenance inspections are vital.

My cottage neighbour recently dug up his tile bed to find the tiles were completely filled with silt and sand. He quickly replaced it with a modern plastic system. It cost less than one thousand dollars, but his simple action will do a great deal to protect his (and our) waterfront. But few cottagers seem interested in septic upgrades and universities are often slow to translate their research findings into lay language. Far too many cottagers neglect the routine cleaning so necessary to protect our precious waterways.

Recreational lakes, in fact, are microcosms of Canadian environmental spending priorities. Underfunding means that valuable lakeshore properties will inevitably become less desirable, gradually losing millions in real estate values as they deteriorate. Such devaluation has already taken place in many North American inner cities where real estate prices have plummetted because of urban decay. Wouldn't it be ironic if coveted vacation properties in this country experienced similar losses because of degraded waterways?

How do you know if your lake is in danger?

The Ontario Ministry of Environment and Energy's Dorset Environmental Science Centre, is wedged between Haliburton Highlands and Muskoka. It is at the heart of some of the most expensive waterfrontage in Canada. While it would be prohibitively expensive for the ministry to regularly sample the thousands of lakes in the area, the Dorset Centre has implemented a unique cost-effective, self-help scheme where it encourages cottagers to monitor their lakes and report findings.

There's a simple way to determine if a lake is oligotrophic (has few nutrients), mesotrophic (has more nutrients), or eutrophic (has too many nutrients). Regular testing must be done to measure water clarity and how much algal growth is taking place because of excess nutrients. If the water seems to be losing its clarity through the years, there are too many algae _ indicating the lake is over-enriched with nutrients.

To measure water clarity, use a Secchi Disk. It's a round, flat disk. The surface is divided into quarters, painted alternately solid black and solid white. A standard Secchi Disk is 20 centimetres (almost eight inches) in diameter and is mounted on metal. (See drawing.)

Away from shore, the disk is lowered into the water and the depth at which it disappears from view is noted. If the disk disappears at a relatively shallow depth (see chart), that indicates there's a lot of algae growing in the lake and is an indication of too many nutrients entering the water.

Cottagers need to know just how dense the algal growth is in their lake and their associations should supply water samples regularly to the MOEE where they can be analyzed to see how much "chlorophyll a" (the amount of green pigment in most plants and algae) is present. The higher the density of chlorophyll a, the more nutrient-enriched is your lake.

Volunteers simply supply the ministry with water samples and Secchi Disk readings about six times each season (from May to September), permitting annual 'check ups' of the health of the lakes, and the ministry analyzes the data. This fine program combines the self-interest of cottagers, with the experience and knowledge of ministry scientists. If there is a more cost-effective way to protect the environment, I have yet to hear about it.

If homeowners on our lakes could only link the environmental facts of life with economic realities, they would demand immediate action to restore and protect our precious water bodies. While public concern about the environment remains high, the truth is that actual spending on real pollution abatement projects and R&D is minuscule compared to other costs, especially debt servicing costs.

The Secchi Disk has been lowered onto an old crib.