1. The fact that we use water does 1. The fact that we use water does not mean that we actually consume not mean that we actually consume it. What does this mean?it. What does this mean?

3. Advantages of using groundwater 3. Advantages of using groundwater as a freshwater resource. as a freshwater resource.

• Groundwater is more reliable than Groundwater is more reliable than surface water (it fluctuates less);surface water (it fluctuates less);

• Groundwater doesn’t need to be Groundwater doesn’t need to be treated as much because soil and treated as much because soil and rock deep underground filter out rock deep underground filter out impurities;impurities;

3. Disadvantages of using 3. Disadvantages of using groundwater as a freshwater resource. groundwater as a freshwater resource.

• Some groundwater may have an Some groundwater may have an unpleasant, metallic taste because of unpleasant, metallic taste because of the presence of minerals.the presence of minerals.

• Minerals also make the water hard Minerals also make the water hard and prevent soap and shampoo from and prevent soap and shampoo from lathering properly.lathering properly.

• Groundwater can become Groundwater can become contaminated by farm runoff. contaminated by farm runoff.

4. Instream uses of water…4. Instream uses of water…

• When water is used without When water is used without removing it from lakes or rivers.removing it from lakes or rivers.

• Hydroelectric power generationHydroelectric power generation

• RecreationRecreation

• FisheriesFisheries

4. Withdrawal use of water… 4. Withdrawal use of water…

• Removes the water from the lake or Removes the water from the lake or river for consumption. river for consumption.

• ManufacturingManufacturing

• AgricultureAgriculture

• Drinking waterDrinking water

5. Why will the demand for water 5. Why will the demand for water increase in the future?increase in the future?

• Increasing populationsIncreasing populations

• Industries get biggerIndustries get bigger

• Increased pollutionIncreased pollution

• Diverting water?Diverting water?

2. How does farming contribute to 2. How does farming contribute to water pollution?water pollution?

• Chemical pollution (pesticides)Chemical pollution (pesticides)

• Biological pollution (from bacteria, ie: Biological pollution (from bacteria, ie: E. Coli)E. Coli)

3. Scientists have called the Great 3. Scientists have called the Great Lakes a chemical soup. Explain.Lakes a chemical soup. Explain.

• Some industries have dumped toxic Some industries have dumped toxic chemicals into the lakes over the chemicals into the lakes over the years… resulting in 360 chemicals in years… resulting in 360 chemicals in the water. (lead, mercury, dioxin, the water. (lead, mercury, dioxin, PCBs)PCBs)

• There may be up to 43 “toxic hot There may be up to 43 “toxic hot spots” in the Great Lakes. spots” in the Great Lakes.

BioaccumulationBioaccumulation

What are 3 main ways water can What are 3 main ways water can become polluted?become polluted?

PHYSICAL POLLUTIONPHYSICAL POLLUTION

• Least harmful, but most obvious … Least harmful, but most obvious … floating garbage, old tires, bottles… floating garbage, old tires, bottles…

BIOLOGICAL POLLUTIONBIOLOGICAL POLLUTION

• Bacteria and viruses that enter rivers Bacteria and viruses that enter rivers and lakes from many sources… such and lakes from many sources… such as sewage. as sewage.

• Approx. 20% of Canadian cities put Approx. 20% of Canadian cities put raw sewage into fresh water… raw sewage into fresh water…

CHEMICAL POLLUTIONCHEMICAL POLLUTION

• This is the most dangerous form of This is the most dangerous form of water pollution. The chemicals are water pollution. The chemicals are usually colourless, odourless, and usually colourless, odourless, and tasteless. Two sources are pesticides tasteless. Two sources are pesticides and herbicides. and herbicides.