Earth Day was a couple of days ago and we thought we would take this opportunity to discuss an environmental issue that is quite Canadian. Canada is one of the wealthiest of countries in regards to its access to water; our supply represents approximately 20 percent of the planet’s freshwater. The Great Lakes alone is the largest surface water system in the world providing 8.5 million people with drinking water and supporting a quarter of Canada’s agricultural capacity.
Fresh water is described as having low concentrations of dissolved solids and salts and occurs naturally in lakes, ponds, ice caps and shields, glaciers, rivers on the surface and as groundwater within underground streams and aquifers. The majority of this water is considered non-renewable, being trapped in ice, locked into underground aquifers, or used up before it even reenters into the water cycle. After you take these facts into consideration, Canada’s renewable (usable) freshwater drops to 7 percent.
Canada also has one of the highest daily consumption of water second only to the United States. Most households and businesses consume 350 L of freshwater a day per capita where the average person needs between 20 and 40 L per day for sanitation and drinking. This may come from the thought that we have so much that we can afford to use as much as we want (I personally could use a lot less if I tried harder.) but we may be putting our water system at risk.
The risks to our freshwater come in many forms. Pollution is the most serious immediate threat. Human activity in the forms of industrial discharges and run-offs can degrade freshwater quality. Run-off from agriculture and detergents contain high nutrient substances that cause large algal blooms which is toxic to wildlife. Biochemical Oxygen Demand (BOD) is created when organic materials are decaying and uses up the available oxygen content within the water. If the oxygen content falls too low, fish and other organisms with suffocate. If the water becomes anaerobic (without oxygen), the decomposition that takes place creates gases such as hydrogen sulphide is poisonous to wildlife. Air pollution can also affect freshwater when it falls as rain, causing acidification and heavy metal accumulation.
Large dams and reservoirs disrupt the natural flow and variations of the water levels that are natural to river systems. They can block the migration routes of fish, alter habitats, trap river-borne nutrients leading to higher algae blooms (that pesky blue-green algae strikes again), colonization of aquatic plants, and greatly increase the surface area of the water exposed to the sun, resulting in higher evaporation rates. This evaporation can also lead to higher water salinity.
Water withdrawal and consumption refers to the removal of water from rivers, lakes and groundwater but not returned to the original source. The highest level of water consumption in Canada is from food production within the agriculture sector in BC, Alberta, and Saskatchewan. Most of this loss in these areas where irrigation is used to improve crop yields and the amount of water is naturally low. The oil and gas sectors are huge consumers of water but fortunately water is reused and recycled wherever possible.
Climate change can compound the effects of all these threats. It affects where and how much rain falls. It also raises temperatures in streams and can contribute to decreases in in the annual spring river flow. Climate projections include frequent severe weather, flooding, and/or droughts will further tax water systems. In a worldview, Canada is not as bad as other areas in this regards but I am sure everyone reading this has noticed big changes in our weather patterns and the severity of our weather in comparison to years ago.
Many things can be done to help save our freshwater and the organisms big and small that depend upon it, including ourselves. Buy organic – this is a more environmentally sound choice and is probably better for your health as well. Avoid anything with plastic microbeads – many body and facial washes have these tiny little beads that have been found in high numbers in the Great Lakes and within the digestive systems of aquatic animals. Discard pollutants properly – do not flush anything potentially toxic down the drain. Unused medications, paints, solvents, household chemicals need to be dealt with properly because a surprisingly small amount of pollutant can contaminate a large quantity of water. Use less – conserve as much water as you can. Shower instead of bathe, do not run your water while you brush your teeth or wash dishes, and avoid watering your grass. These are all things we have been told for years but we all need to be more vigilant in adhering to them, me most definitely included.
Next week will be a continuation on this topic with an look at some of Canada’s largest waterways. Be sure to take a look.