1Good morning and welcome to yet another lecture in Environmental Science.
2I don't think I'm telling you a secret when I mention that water is a big worry here in Australia.
3The stuff is scarce.
4Perhaps that's why we drink so much beer, eh?
5Seriously, though, a safe and reliable source of water is one of the great concerns of people everywhere.
6Moreover, as the world population grows,
7the pressure on existing water supplies grows greater and greater.
8Think about it.
9Our economic system demands that there be more and more consumers.
10The growing number of people has been tied to climate change, including droughts.
11So more people means less water.
12But our economic system demands a high birth rate.
13Forget about oil. Soon enough you will see wars for water.
14Mark my words.
15But today, I'm going to confine my remarks to Australia.
16As noted already, here down under, the water supply is extremely scarce.
17The only drier continent is Antarctica
18and remember, no one really lives there anyway.
19Moreover, in recent years, the wind patterns have changed.
20Rain that used to fall on the country now falls out to sea hundreds of miles to the south.
21Now, when I speak of people needing water, most of you probably think of drinking.
22Certainly everyone needs water for drinking.
23But surprising as it may sound,
24drinking is not anywhere near being the main use for water.
25Most water is actually used for washing.
26When you take a shower, you probably use well over a hundred litres of water.
27Every time you flush your toilet, that's about 8 litres.
28But most people drink no more than two litres or so per day.
29So, where to get water?
30It could be obtained from rainwater,
31but often rainfall consists of other harmful pollutants that evaporated with the water.
32In fact, acid rain, an intense example of this,
33causes harmful effects on the wildlife of the habitat on which it falls.
34Water from underground could also be used,
35though it is more difficult to contain
36and often must go through an extensive cleansing process.
37The purest water is found in rivers, creeks, lakes, and dams.
38And, sad to say, Australia has precious few of these.
39Really, how many of your home towns have rivers?
40Year-round rivers, I mean.
41The soil tends to be sandy, so water soaks into the ground.
42Many places are rocky too,
43so 87% of the rainfall is lost to evaporation.
44That's almost twice the evaporation rate in my native Canada!
45Speaking of rain, we already heard how rainfall is diminishing here in Oceania.
46The quantity itself isn't the only problem, either.
47Going back to the problems with obtaining rainwater,
48a further problem is that rain is a useful source of water only if air pollution is fairly mild.
49Again, you're in a situation where you can't win.
50You need water where most people live.
51People tend to build cities where rainfall is adequate.
52But then modern cities tend to feature polluted air
53which renders the rain far less easily usable.
54OK, let's take a look at the table here,
55you'll see it showing the relative pollution of rainfall in the world's cities.
56The more people, the dirtier the rain.
57This is becoming a huge concern for people in the West,
58who want their water to be pure and safe.
59Though reliable drinking water is important everywhere,
60the concern in the West is reflected in all the government regulations and political campaigns aimed at solving this problem.
61In contrast, there are not as many demands made on the governments in Asian and African cultures to improve the water,
62as their focus is on other issues.
63Now, whatever the source of water,
64we can never afford to forget that all water is highly vulnerable to contamination.
65Whether we're getting it from the ground, from bodies of water, or rainfall,
66it is susceptible to a variety of toxins.
67In fact, that's why we clean it before using it:
68water carries with it filth and dirt.
69This problem shows up in a number of different ways.
70As humans and all other animals need water to survive,
71it's no surprise to us that one of the most important domestic uses of water is for drinking.
72Yet if you have old-fashioned lead pipes,
73you may slowly be poisoning yourself by drinking that nice clear water.
74The industrial pollution, farm chemicals, and leaky landfills
75are well-known sources of contaminants as well.
76So what is being done to ensure we Australians a safe and steady supply of drinking water?
77There are a lot of initiatives that make admirable efforts to remedy this issue.
78We'll be talking about this when we meet again on Thursday.
79But, as a preview,
80I can tell you that so far the amount of real solutions that have been produced is not nearly adequate.
81Traditionally, we've been very free in this country.
82That means that every person and every province tend to go its own way.
83So the mechanisms for water management are, in a word, insufficient.
84To begin seeing how this is so, I want you to read something before our next class.
85Though a lot of previous data on water usage and water management are inconclusive
86and have thus caused quite a concern,
87we can learn a lot from the contents of reports written on the subject.
88The basis for the government's water policy is the 1989 White Paper
89reporting on "Water Use: Present and Future".
90If you compare the numbers offered in the paper with those in the text,
91you'll find that the report is rather untrustworthy.
92Truth being told, I'm being too kind when I say that!