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Water Conservation Every Drop CountsThe importance of protecting our water resource cannot be overstated. In economic terms, the measurable contribution of water to the Canadian economy is difficult to estimate. In environmental terms, water is the lifeblood of the planet. Without a steady supply of clean, fresh water, all life, including human, would cease to exist. The perception that Canada is blessed with an abundance of fresh water has led to misuse and abuse of the resource: from household toilets that use 18 litres per flush where 6 litres would do, to industrial plants and some municipalities that use water bodies as convenient sewers. In 2001, the average Canadian daily domestic use of fresh water per capita was 335 litres. The quantity, quality and economic problems we face as a result of our use of water are complex but, at least one of the causes of these problems is easy to manage the way we waste water. And, the solution is straight forward water conservation. Simply stated, water conservation means doing the same with less, by using water more efficiently or reducing where appropriate, in order to protect the resource now, and for the future. Using water wisely will reduce pollution and health risks, lower water costs, and extend the useful life of existing supply and waste treatment facilities. And it's easy. With little change to the way we do things now, or the equipment we use, we can reduce water consumption in the home, and in business, by 40% or more. These pages outline the role of water conservation in addressing problems related to water use and water quality. It also shows us what part we can play as residential consumers in finding solutions. Sustaining our water supplyWater is considered a renewable resource: "renewable" referring to that portion which circulates back and forth in the hydrological cycle (described more fully in Freshwater Series A-1, "Water Nature's Magician"). However, pressures on the resource are growing. For example, between 1972 and 1996, Canada's rate of water withdrawals increased by almost 90%, from 24 billion m3/yr (cubic metres per year) to 45 billion m3/yr. But, our population increased by only 33.6% over the same period, illustrating the growth in our thirsty lifestyles. As the readily available supplies of fresh water are being used up, we begin to see that there are real limits to how much water we can count on. Limiting factors
We can, however, make a significant contribution to solving these problems by reducing unnecessary levels of water use. To do so requires that we identify the areas within our homes, businesses, buildings and processes where we waste water and then make appropriate changes, either in our fixtures, or in our water-using habits. How water is usedWe use water in many ways, and assign different values to those uses. Instream uses (e.g., for transportation and recreation) are valued highly, but it has proven difficult to give them a dollar value that has any real meaning. For example, just what would the average consumer be willing to pay to swim in a clean lake or for a chance to catch fish in a clean, unpolluted river? By far the greater number and variety of water uses occur on land. These are called withdrawal uses and, although important to our daily lives, they have tended to be assigned a low value. Water is withdrawn, used and then discharged. Most withdrawal uses "consume" some of the water, which means less is returned to the source than was taken out. And, after it has been used, the quality of the water that is returned is often diminished, which has a negative impact on both the environment and recreational instream uses. In 1996, five main withdrawal uses accounted for a total annual water intake (extractive uses) of 44.6 billion m3. These uses are described more fully in Freshwater Series A-4, "Water Works!". Thermal power generation includes both conventional and nuclear power generating plants, which withdrew slightly more than 64% of the total water intake in 1996. Manufacturing accounted for 14% of water withdrawals in 1996. Paper and allied products, primary metals and chemicals were the main industrial users. Agriculture accounted for nearly 9% of total withdrawals, with the semi-arid Prairie region of Canada accounting for 75% of this total. Agriculture consumes a large portion of what it uses, returning less than 30% to its source where it can be used again. Irrigation is the largest agricultural consumer of water. Municipal use accounted for 10% of all water withdrawals in 1996, or 12% when similar rural uses were included (excludes industrial uses and large-scale agriculture). In the municipal sector, more than half of the water demand is a result of residential use. Mining use, including metal mining, non-metal mining, and the extraction of coal, accounted for 1% of all water withdrawals in 1996. Water is used by the mining industry to separate ore from rock, to cool drills, to wash the ore during production, and to carry away unwanted material.
Sustaining our infrastructureWhile many communities have access to an abundant water supply, the costs of the infrastructure that provides homes and industry with water and sewer services are straining the available municipal financial resources. By infrastructure, we mean the water treatment plants that purify our water, the water mains in the ground that transport water, and the towers and reservoirs that store water. The term includes the sewer pipes that carry away wastewater and the sewage treatment plants that treat wastewater before returning it to the environment where it often becomes the source of water for communities downstream. Experts are predicting a growing problem involving municipal water and sewer infrastructure in Canada. In 1991, the value of this investment was estimated to be worth over 90 billion dollars, of which a significant amount is deteriorating with age. An increasing number of Canadian municipalities are considering water conservation as the key to keeping expansion needs to a minimum. Water conservation also optimizes plant efficiency, while assisting municipalities in financing the replacement of infrastructure that may be over 50 years old in some communities and up to 100 years old in several others. Communities with older systems in need of extensive repairs or replacement face the most difficult problems. With all levels of government adopting policies of realistic water pricing and user pay principles, many municipalities have instituted full cost pricing to recover the total cost of providing both water and sewer services including the costs of financing the replacement of older systems and the upgrading of overloaded treatment plants. Higher municipal costs, in turn, mean higher water and sewer bills. The problem of stressed treatment systems is not restricted to communities with piped water and sewer systems. Over the past 25 years, there has been a substantial migration of urban dwellers to the countryside. City-bred water using habits and attitudes are, in many instances, lowering the water table. And, the flood of wastewater produced is stressing the soil's ability to treat septic effluent adequately. For both urban and rural communities, water conservation can extend the life of this over-stressed infrastructure.
Sustaining our water qualityIn addition to water supply and infrastructure issues, water quality is a problem in many Canadian communities. Generally speaking, the decline in water quality is a function of the way we use water. Even something as simple as rinsing dishes in the kitchen creates wastewater that is contaminated to some degree. Once this water enters the sewer system, it must be treated in a sewage treatment plant. These facilities are never 100% effective, which means that some water quality deterioration remains after the treatment process. Specific causes of impaired water quality are numerous, including: agricultural runoff containing the residues of fertilizers, pesticides and other chemicals, industrial pollution, either directly from the facility, or indirectly from the leaching of chemicals from landfills, or pollution from average households in the form of improperly treated municipal sewage (refer to Freshwater Series A-3, "Clean Water Life Depends in It"). Nearly 75% of Canadians are serviced by municipal sewer systems. In 1999, 97% of the Canadian population on sewers received some form of wastewater treatment. The remaining 3% of Canadians served by sewage collection systems were not connected to wastewater treatment facilities in 1999 and discharged their untreated sewage directly into receiving water bodies. For the roughly 25% of the Canadian population served by private wells and septic disposal systems, the news is not much better. These systems were originally designed for houses that were widely separated from their nearest neighbour, such as farmhouses and the occasional rural residence. Yet, today, in many parts of the country, individual private wells are being installed in subdivisions at suburban densities. The primary danger here is that too many wells may pump too much water for the aquifer to sustain itself. Septic treatment systems associated with these developments can stress the environment in a number of other ways. They are often allowed in less than satisfactory soil conditions and are seldom maintained properly. They are also unable to treat many household cleaners and chemicals which, when flushed down the drain or toilet, often impair or kill the bacterium needed to make the system work (The same applies in urban systems). The end results are improper treatment of wastewater if not outright failure of the system and the contamination of adjacent wells with septic effluent containing bacterium, nitrates and other pollutants. Once these contaminants are in the groundwater, they eventually reach rivers and lakes. In other words, once we have a pollution problem, we may be only a step away from a water supply problem.
Individual action conserving water in the home, community and at workAs we have seen, water quality and quantity are two sides of the same coin. How does saving water help water quality? Because water saved is water that does not end up in the wastewater stream requiring treatment. This, in turn, reduces municipal pumping and treatment costs and frees up monies that can be used for infrastructure renewal and replacement and protection of supply sources. Less wastewater in the sewage treatment plant also means that the plant has a better chance of doing the job it was intended to do. So where do we start? The first step is to identify where we use water in the home. Then we need to decide on what to do to reduce the amount of water we use, either by eliminating wasteful practices and habits, or by improving the efficiency of our water using fixtures and devices. Since we waste so much, this should be a relatively easy and painless process. The prime area to target is the bathroom, where nearly 65% of all indoor water use occurs. What follows are some suggestions for how to get your house or business in order. Based on the three rules of water conservation reduce, repair and retrofit a typical household can reduce water consumption by 40% or more, with or no effect on lifestyle. ReduceMuch of the water "consumed" in our daily activities is simply wasted. Taps are left running while we brush our teeth. Dishwashers and laundry machines are operated without full loads. Really, everywhere we use water there is room for improvement. Here are just a few examples for both indoor and outdoor water use.
RepairLeaks can be costly. A leak of only one drop per second wastes about 10 000 litres of water per year. Most leaks are easy to find and to fix, at very little cost.
RetrofitRetrofit means adapting or replacing an older water-using fixture or appliance with one of the many water-efficient devices now on the market. While these solutions cost more, they also save the most water and money. Retrofitting offers considerable water saving potential in the home and business, so this issue in the Freshwater Series is devoting considerable space to it. 1) Toilet retrofitsWhen it comes to retrofitting, the prime fixture to target is the toilet. You can: i) adapt your existing toilet in a number of ways, by installing certain water-saving devices inside the tank at the back of the toilet; or, ii) if the toilet is more than fifteen years old which means it probably uses about 18 or more litres of water per flush you can replace it with one of the growing number of ultra-low-volume (ULV) toilets, that can be ordered from most plumbing outlets, and use only 6 litres or less per flush. There are many toilet adaptations you can install in the tank of an existing toilet to reduce the amount of water used in a flush cycle. These devices fall into three generic categories:
The most common water retention device available is the toilet dam. A set will save about 5 litres per flush when installed properly. Their main attraction is their low cost (under $10.00 per set) and the fact that they are easy to distribute and install for example, as part of a wider municipally-sponsored retrofit program. Their main disadvantage is that they tend to leak over time by slipping out of adjustment and can slip free and interfere with the moving parts inside the toilet tank, if not routinely checked. Toilet dam and displacement bag: The water displacement devices familiar to most people are the plastic bags or bottles filled with water which are suspended inside the toilet tank. As the name implies, these devices displace several litres of water, saving an equivalent amount during each flush. Like the toilet dam, most displacement devices are inexpensive and easy to install. Their chief disadvantage is that they don't save as much water as other devices and, if they are not installed carefully, they can interfere with the proper operation of the toilet. One displacement device to stay away from is the brick! It can disintegrate inside the toilet tank, leading to excessive leakage at the flapper valve and may even be heavy enough to actually crack the tank. There are essentially two types of alternative flush devices: early-closure and dual-flush. They are usually attached to the overflow tube inside the toilet tank (Figure 9). In both cases, they close the flush valve or flapper after the tank is only partially emptied. In theory, this interruption in the flush cycle occurs after the bowl has been cleared. In the case of the dual-flush mechanism, the amount of water saved is dependent upon how long the flush lever is activated a partial flush for light duty or full flush or heavy duty. While all of the above toilet adaptations appear to work as intended when first installed, their performance may vary considerably, depending on the toilet design. The best advice is to monitor the performance of the devices periodically. If you discover that it becomes necessary to double flush the toilet, something is in need of adjustment or replacement. Remember that double flushing defeats the purpose of your water conservation efforts and is costing you money. If you decide that it is time for a toilet replacement in your home or business, you are well on your way to significant water savings that you can bank on over the life of the toilet. Replacing a 18 litre per flush toilet with an ultra-low-volume (ULV) 6 litre flush model represents a 70% savings in water flushed and will cut indoor water use by about 30%. Keep in mind that 18 litres per flush, assuming 4.5 flushes per person per day, translates into nearly 30 000 litres of clean, fresh water per year just to get rid of 650 litres of body waste. A 6 litre flush toilet only use about 10 000 litres to do the same task. Low flush toilets are available for less than $150.00 at most plumbing and supply stores. Remember, the ULV toilet not only uses less water, it produces less wastewater. If your municipality applies a sewer surcharge on your water bill, the investment in the better toilet could translate into a 50% reduction in your combined water/sewer bill. If you are on a private well and septic system, you are significantly reducing the loading on your tile field while extending its useful life. To a lesser degree, the same applies to the other water-saving devices described in these pages. 2) Showerheads and faucetsAfter the toilet, the shower and bath consume the most water inside the home. Conventional showerheads have flow rates up to 15 to 20 litres per minute. A properly designed low-flow showerhead can reduce that flow by half and still provide proper shower performance. Low-flow showerheads can be purchased in most plumbing supply outlets. Depending on your preference for finish and appearance, you can select a serviceable low-flow showerhead starting at around ten dollars. Consider one with a shut-off button. The advantage of the shut-off button is that it allows you to be really water efficient if you so choose, by being able to interrupt the flow, while you lather up or shampoo, and then resume at the same flow rate and temperature. Beware of the type of showerheads that produce such a fine mist that the water is quite cool by the time it reaches your feet. And, stay away from so-called flow restrictors that are inserted inside your existing showerhead. They look like a small plastic washer and can produce a fierce, stinging spray pattern which may significantly reduce the enjoyment of taking a shower. Conventional faucets have an average flow rate of 13.5 litres of water per minute. Install low-flow aerators to reduce this flow. In the bathroom, a flow rate of about 6 litres per minute should do the trick, and in the kitchen a flow rate of 6 to 9 litres per minute is sufficient. Don't bother retrofitting the tap in the utility sink; it is intended to provide large volumes of water quickly, for example, for cleaning or washing, such that low flows will only inconvenience the user. 3) OutdoorsDuring the growing season water use can increase by as much as 50%. While lawns require a lot of water, much of this water is wasted lost due to overwatering and evaporation (see Reduce). Watering equipment also plays a part in how much water is saved and lost. Ideally, sprinklers should be suited to the size and shape of the lawn. That way, you avoid watering driveways and sidewalks. Installing timers on outdoor taps can be a wise investment. Sprinklers that lay water down in a flat pattern are better than oscillating sprinklers which lose as much as 50% of what they disperse through evaporation. Drip irrigation systems which apply water only to the roots zone are the most efficient and the most expensive alternative. The water you use to water your lawn doesn't have to come out of a tap. A cistern, which captures and stores rainwater, can be used as a source of irrigation water. A rain barrel can adequately fulfil this function. Finally, consider a low-maintenance landscape one which requires little more water than nature provides. Often called xeriscaping, the principles of a low-maintenance landscape are as follows:
The most significant savings of course, come from a reduction in lawn area and switching from exotic plant forms to native species which require less water. In general, lawn areas should not exceed what is useful for play and social activities, and should be limited to the backyard where the family spends the majority of its time.
The bottom lineWater conservation. The message is clear. If we each save a little, it can add up to major savings in water, energy and money. For the average household, reductions in water use as high as 40% or more are feasible, just by following the steps outlined in this issue in the Freshwater Series. The benefits don't stop at the household or business. The municipal water and sewer department gets a break on the amount of water it has to pump to our homes and businesses and on the amount of wastewater it has to treat in sewage treatment plants. Water conservation can extend the useful life of municipal water supply and treatment plants, and will benefit the operating efficiency and life expectancy of private septic disposal systems. And, finally, water conservation can generate significant environmental benefits. It can reduce water diverted and the pollution loadings on our lakes and rivers by reducing the volumes of wastewater which we have to treat. This can help to protect our drinking water and the ecological balance in sensitive aquatic ecosystems. If we all practice water conservation, everyone and everything benefits. Freshwater Series A-6Note: A resource guide, entitled Let's Not Take Water For Granted, is available to help classroom teachers of grades 5-7 use the information from the Water Fact Sheets. Text prepared under contract by REIC Ltd., Toronto
Published by authority of the Minister of the Environment |
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