How Much Water Do We Have ?

Part 2 from Rideau Valley Conservation Authority

Eastern Ontario is blessed with a sufficient quantity of good quality water to do most everything we want to do … it is a liquid legacy that is the envy of the world.   While we sometimes experience local gaps in supply or quality at certain times of the year or as a result of particular man-made events, we generally have plenty of water for our needs. However, with our abundant water comes a responsibility not to waste it so we can ensure there is enough for fish, wildlife, instream needs and for future generations.

How much water we get and where it goes in the watershed is known as the water budget.  In our area, we have traditionally received an average of 912 mm of water a year as rain and snow.  An astonishing 547 mm of that (60%) is very quickly lost back to the atmosphere either through evaporation or humidity after being used by plants.  That leaves 40% or about 365 mm to flow through the valley as lakes, streams and groundwater to be used by animals and people in various ways.

Wetlands: About 13% of the Rideau and Mississippi watersheds are covered by marshes, swamps, bogs and fens.  These wetlands provide many valuable ecological services to the people of the valley such as flood reduction, wildlife habitat, erosion protection, water cleansing and groundwater recharge. 

Lakes/Rivers/Streams: The beautiful surface waters of the Mississippi and Rideau valleys provide other valuable products and services for people.  These include residential sites, recreation of many kinds, fish and wildlife and a lot of peace and quiet.  Surface water made up of lakes, rivers and streams is estimated to cover about 7% of the local land mass.  Combined with the estimated 13% covered by wetlands means about 20% of our region is water!  This is much greater than most other areas of the world.

Groundwater: Only 10% of our rain and snow makes its way down through the soil to replenish our underground water sources (aquifers).  In the Mississippi and Rideau watersheds, groundwater is critical to the nearly 140,000 people who rely entirely on wells for their daily potable water.  Fortunately, scientists tell us that there is much more water underground than we see on the surface.  While there seems to be plenty of local groundwater, we can experience periodic shortages due to seasonal or man-made fluctuations. 

Drinking water: Drinking water use (both from municipal systems and private wells) accounts for less than 1% of the total amount of water available in our area.  Agriculture and industry use even less than that.

In the end, our demand is fairly low in relation to the amount of water available in Eastern Ontario.  Supply however can vary from day to day, month to month and year to year depending on weather, climate, land cover and human uses or abuses.  Canadians are among the heaviest water users in the world with each of us using 300+ litres of water each day! Even in our region it is good practice to use water wisely so we can keep our supply and demand balanced for years to come.  This balance is critical for the health and well-being of our watershed residents.

Next topic:      Who protects our water supplies?
 

 
For more information:            Sommer Casgrain-Robertson
                                               Co-Project Manager
                                               Mississippi-Rideau Source Protection Region
                                               1-800-267-3504 or 613-692-3571 ext 1147
                                               sommer.robertson@mrsourcewater.ca

Water Use & Protection 1 - The Importance of Water

From the Rideau Valley Conservation Authority 

       
 This is the first of four backgrounders on the sources, use and protection of our local water supply right here in Eastern Ontario.   These four articles will give lots of food for thought as we celebrate World Water Day on March 22.

           Water appears in many forms in our lives…lakes, rivers, wetlands, groundwater and drinking water among others.   Each is important to humans and to many other forms of life which depend on it, and each form of water is linked to all other forms.

Wetlands:       Wetlands cover about 15% of our area providing huge benefits in terms of flood reduction, recharge of the underground water for wells, habitat for plants and animals, waste treatment and nutrient recycling.  A recent Ontario study calculated that wetlands provide an estimated value of $247 per person per year in these so-called ecological goods and services.   In other words, Mother Nature through wetlands does for free what we would otherwise have to pay millions of dollars to do through technology and infrastructure.    When we remove the wetlands, we lose the services.

Lakes: The beautiful Rideau Lakes and many others of Eastern Ontario add huge value and interest to the lives of residents and visitors alike.   All of the recreational pursuits suitable to lakes (fishing, boating, birding, swimming) are healthy antidotes to the high stress of our urban lives.    The tourism value of the lakes creates millions of dollars in revenue for the municipalities and the businesses in the area.   Lakes occupy less than 5% of the local landscape but remain as one of the most memorable and sought-after places for vacations and, increasingly, retirement living.

Rivers/streams:         The rivers, streams and creeks that make up the drainage pattern of the area is under stress.   People tend to clear cut or harden the banks of small local streams under the mistaken impression that these watercourses are of little value.   In fact, the tissue of small tributary feeder streams to the Mississippi, Rideau or Ottawa Rivers can easily be 30 times longer than the main rivers themselves!   And research shows us that these tributaries are often in poorer environmental health.  Taking care of the “tribs” is often the first course of action in taking care of the big rivers.

Groundwater:  Studies show that about 17% of the people in the Mississippi and Rideau watersheds (over 140,000 people) rely on groundwater and wells as their daily source of household water.   Groundwater is vulnerable to whatever type of activity is happening on the ground surface above.  It becomes important to know and protect the areas around the well head from storage, use and spills of hazardous materials.   Groundwater also flows eventually into rivers and streams keeping up the supply of surface water even during surface droughts and extended hot weather.

Drinking water:           This one’s fairly obvious.   Canadians use a whopping 300+ litres of freshwater each every day for domestic purposes such as drinking, cooking, toilet flushing and washing.    Drinking water is one of the smallest portions of our local water use (less than 1% of the available water in the valley) but is certainly the most important.  Celebrating and protecting water for its essential value to our way of life is a little self-serving but it does get the job done.    If we do it for ourselves and our families, our entire environmental, social and economic systems will benefit too.

Next week:      What is our local water supply situation like?
 

For more information:            Charles Billington
                                               Rideau Valley Conservation Authority
                                               613-692-3571  or  1-800-267-3504 ext 1116
                                               charles.billington@rvca.ca