Success stories - Metro US

Success stories

Sometimes threats to the environment we are dealing with these days seem daunting. Global warming, deforestation, polluted air and water … the list goes on.

Certainly these are grave problems requiring international co-operation, however, international co-operation to solve an environmental problem is not without precedent. Although difficult, it has happened on several occasions and threats to the environment have been removed and environmental conditions have improved.

Since your columnists inhabit the Great Lakes area, one of the first to spring to our minds is Lake Erie. In the second half of the 20th century the water quality in Lake Erie declined dramatically due to phosphorus run-off. The high phosphate levels caused eutrophication and resulted in algal blooms. When this algal biomass started to decay it used up a large amount of the oxygen dissolved in the lake’s water. The low oxygen concentrations in the water then led to fish kills. The large numbers of dead fish caused water quality to decline still further. At one point, one of Lake Erie’s tributaries in Ohio actually caught fire. As you may have guessed, unpolluted water doesn’t burn so this was an indication something was very wrong.

However, in 1972, the U.S. Congress passed the Clean Water Act and an agreement was reached between the U.S. and Canada regarding the control of phosphorus entering the lake. Over time water quality in Lake Erie improved. By the mid-1980s, Lake Erie was an entirely different lake. Fish populations rebounded and the lake and its tributaries no longer caught fire.
Another example of international co-operation that has resulted in positive change is the Montreal Protocol. This international agreement concerned the ozone layer and the control of substances such as chlorofluorocarbons (CFCs) that deplete the ozone layer. In 1985, it was reported that the ozone layer, a layer of gas that prevents harmful ultraviolet light rays from reaching the Earth’s surface, was significantly thinner and holes in this layer had appeared over the Arctic and Antarctic. CFCs were, amongst other things, used as propellants in aerosol sprays such as hairspray, which people used a lot of in the 1980s.

The Montreal Protocol, which phased out CFCs, was drafted in 1987 and came into force in 1989. Since then, ozone destruction has slowed and some projections have been made that, by 2050, the holes in the ozone layer will have closed up and the ozone layer will have recovered.

Of course Lake Erie and many other lakes in Canada still face damage from nutrients and other forms of pollution, invasive species, and a host of other challenges, and we all still need to slather on the sunscreen, but significant progress has been made on these fronts and should give us encouragement on others.

– Sophia Dore is an environmental scientist with Conestoga-Rovers & Associates. Andrew Laursen is an assistant professor at Ryerson University; earthtones.metro@gmail.com.

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