FRESHWATER, AN INDICATOR OF SUSTAINABLE SOCIETY
D. W. Schindler
Brock University’s location near the outlet of the Great Lakes, estimated to contain 20 percent of Earth’s fresh water, has inspired me to choose the topic of today’s address.
Of all the Earth’s natural resources, freshwater is the scarcest. Many countries already have insufficient water for agriculture. Three billion people, half of the world’s population, do not have access to enough freshwater for proper sanitation. There are 250 million reported cases of waterborne diseases per year, probably a small number compared to those that are not reported. Five to 10 million deaths are reported annually from water-related diseases. The incidences of waterborne diseases and deaths are increasing, despite modern advances in technology and health care.
One must ask what the state of our freshwaters will be in another 40 years, when the human population is expected to be 9 million, not the 6 million that it is today. For the past century, water use has increased more rapidly than human population growth. Freshwater has been the real power behind the green revolution that has allowed us to feed the world, because increasing irrigation has been the key to the green revolution. Use of freshwater for irrigation has increased 5 fold in the past century. It is by far the major human use of water. But irrigation has left a legacy of dams, dry riverbeds, extirpated salmon runs, and salinized lands. Of all of the Earth’s freshwater runoff, humans already appropriate over 50 % for their own use, and this is expected to increase to 80% within the next 25 years.
Canadians are the world’s most profligate users of freshwater, probably because we perceive that it is abundant in this country. An average Canadian uses 200 liters of water a day, about 4 times the rate of most European citizens and many times the amount available to most Third World residents. We tend to assume that our water needs little treatment to be safe for drinking, and that freshwater fish are abundant and easily caught. Neither of these assumptions are true at present. In addition to large increases in Canada’s human population, agriculture, forestry and industry have grown. Politicians tout the economic prosperity from these activities. They do not mention the invisible, but increasing costs of water and sewage treatment, medical treatment of waterborne diseases, or degraded fisheries. These costs are borne by ordinary Canadians, not by the industries that cause them. Sadly, we have paid the price of financial well-being with freshwater. Scientists have known this for many years, but no one listens.
In the past year, the tragedies at Walkerton and North Battleford have provided a wakeup call. We now realize that Canada is not immune from freshwater problems. The costs of these tragedies have not yet been calculated, but will certainly run in the millions. The national costs of water problems are also large, and at present they are hidden from public view. American statistics are more complete, and indicate what we can expect to find:
According to a study by the American Society for Microbiology, which has a membership of 42000 scientists, there are 900,000 cases of water-caused illness in the USA each year. An average of 900 people die. Children, pregnant women, and those over 55 are very vulnerable. So are immune-compromised people such as those with AIDS, and those receiving radiation treatment or heavy doses of antibiotics. These vulnerable sectors represent over 25% of the population in both the USA and Canada. In particular, those 55 and older represent the most rapidly-growing portion of the North American population. Seventy percent of diarrheal deaths occurred among this group. Unless we take effective action, the costs, in lives and in medical expenses, will continue to rise.
The financial costs of ignoring water have been high. The cost for medical treatment per case of waterborne illness has been estimated to range from $200 for mild cases to $8000 or more for more extreme cases, not including lost productivity. The 1993 Cryptosporidium outbreak in Milwaukee, which caused over 100 deaths and tens of thousands of cases of gastro-intestinal illness, cost over $ 55 million alone. Lost economic activity is also costly. The 1997 toxic Pfiesteria bloom on Chesapeake Bay, which is widely believed to have been caused by runoff of wastes from intensive livestock operations in the basin, caused $43 million in economic losses. It also killed millions of fish in the rivers and estuaries where the algal blooms developed.
It is not surprising that freshwaters species are among those most endangered throughout the world. In North America, a recent summary found that from 30 to 70 percent of the species in different groups of freshwater organisms were either extinct or threatened with extinction. The reasons vary, but most are related to habitat destruction, chemical pollution, or the invasion of alien species. All three are indicative of bad management of freshwater. The Great Lakes are an example. Containing 20% of the world’s freshwater, many native species are threatened by one or more of the over 145 alien invaders, largely because of lack of legislation to prevent the discharge by ships of ballast water from other continents. Wetlands and other shoreline habitats have been destroyed. The remaining fishes, native and alien alike, are so toxic that fishermen must consult guidebooks to determine how much of them can be eaten without risk. Some alien invaders, such as sea lampreys and zebra mussels, have caused billions of dollars in economic damage. We should be ashamed of what we have done to the Great Lakes. The environmental destruction is unequalled on this continent, even by the extirpation of the plains bison and the passenger pigeon. Yet in international negotiations among Great Lakes bureaucrats, the euphamism “sustainable development” is still applied to the lakes!
The Walkerton and North Battleford incidents have to calls for more and
improved standards, and for improved treatment technology. I do not consider
these to be the most important priorities. Most of the science and technology
to protect freshwaters, freshwater species and their habitats, and human
water supplies has been available for decades, but we have ignored it.
Our biggest shortcomings are in social, ethical, political and even theological
dimensions. Community leaders and private citizens must take action to
see that our knowledge of freshwater is properly applied, to protect the
aquatic ecosystems that are so critical to sustaining the lives of humans
and all other species.
Provinces usually stand by as land is developed and water use is intensified
until provincial water quality “guidelines” are approached
or exceeded. By then remediation is usually slow and costly. The role
of the federal government has been reduced to providing research, with
provinces subsuming most of the regulatory responsibility. Federal science
laboratories have produced much good and useful aquatic science, but it
is seldom used in making decisions that affect freshwaters. Also, their
research budgets have not kept pace with the increasing number of problems,
or the escalating costs of doing science. It is critical that we do not
allow this fragmentation of responsibility to continue.
A second important component is the protection of riverbanks (riparian areas) and wetlands. Communities, pastures and fields are usually constructed right to the banks of lakes and rivers, destroying the natural flora that protects freshwaters from catastrophic events or human errors in upland areas. Wetlands are typically drained or filled in, removing a catchment’s ability to slow water runoff, filter out pathogens and silt, and to remove nutrients. As a result, we get more frequent and more catastrophic floods, and watercourses befouled by silt, nutrients, pathogens, pesticides and other contaminants. Over 70% of wetlands in southern Canada have been destroyed.
A third component, closely linked to the above two, is land-use change, which causes accelerated runoff of nutrients and soil erosion. As forests are converted to pasture, nutrient runoff to freshwaters increases by several-fold. It increases still more if converted to croplands. The effects of these changes on watercourses can be minimized by the protection of riparian areas and wetlands.
Municipalities are no better at land-use planning. Most (but not all) large Canadian cities now treat their sewage. But the quality of treatment is variable. Most cities reduce pathogen discharges to receiving waters, but few remove the nutrients that cause algal blooms, which in some cases produce toxins, or at least taste and odor problems. Most cities combine their storm drains and sewage, bypassing treatment plants during periods of high flow such as during storms, when treatment plants cannot handle the volume. The result is that mixtures of untreated human sewage, pet excrement, pesticides and lawn fertilizer are diluted to varying degrees by rainwater, then flushed directly into watercourses. This must change.
Solutions are obvious: The protection of watercourses must take precedence over individual land use rights. Don’t allow the destruction of riparian areas and wetlands. Limit the amount and timing of fertilizer and manure application. Don’t allow combined storm drains. Require that highly concentrated populations of both humans and animals have complete sewage treatment, using methods that remove both nutrients and pathogens. Minimize consumptive water uses that deplete river flows, such as irrigation and water diversion. Do not build the dams that prevent fish migration, destroy channel integrity, and cause remaining fisheries to become contaminated with mercury to the extent that they are unacceptable for human consumption. Low volume toilets, low flow showerheads, and limited lawn irrigation are other methods that individuals can use. Communities can encourage water conservation by pricing water supplies so that price increases in proportion to water used. In most areas, it is now the opposite. Profligate water users are rewarded by very low prices, so that there is little incentive to conserve.
We also make rather extravagant use of water treatment. It is absurd that water used for flushing toilets, watering lawns, and industry receives the same degree of water treatment as drinking water. This will change in the years ahead. It is no coincidence that this year’s Stockholm Water Prize will be awarded to Dr. Takashi Asano for his pioneering work in treating water for reuse in different purposes with differing water quality requirements.
There are new and important roles for science, technology and standards. New and unanticipated problems are emerging constantly as humans develop more novel chemicals and develop new ways to exploit the Earth’s ecosystems. For example, in the last few months, it has been reported that the perfluorinated chemicals that have served as surfactants in many industrial processes are both transported long distances in the atmosphere and bioaccumulated. Brominated chemicals used as fire retardants have been shown to have many properties similar to PCBs. The biogeochemistry and toxicology of these and many other chemicals are almost unstudied. While modern water disinfection processes have been magnificent technological advances that have vastly reduced the threat of disease in technological societies, most have some disadvantages, such as the formation of small amounts of carcinogens or chemicals that cause taste and odor problems. While these are insignificant when compared to the diseases that they eliminate, improved water treatment techniques can potentially eliminate them. This will become increasingly important if humans continue to multiply both in numbers and per capita consumption of ecological resources.
In summary, freshwater is becoming too precious to leave its fate in the hands of engineers and water treatment plant operators. To ensure that we have freshwater of sufficient quantity and quality in the 21st century, and to preserve the aquatic species that are an important part of Canadian heritage, we must all become engaged, for water protection is a multi-faceted, multidisciplinary task. One of the most fateful errors of the 20th century is that we have assumed that science and technology will look after our wellbeing. But science and technology do no more than offer new tools. It is up to the rest of us to see that the tools are effectively used.
In summary, if the abuse of freshwater continues at the rate that it has in the 20th century, the result will be catastrophic. The costs of water and sewage treatment will continue to rise, as will the medical costs for treating those with waterborne diseases. Sport fishing for predatory fish species will be unknown by mid-century. At best, the cost to Canadians will be tens of billions of dollars. Your generation has the opportunity to reverse the sad freshwater legacy that my generation has left you. If you do not, by the time your children attend a university commencement address two decades from now, much of the damage will be irreversible. Leave them a legacy that my generation has failed to leave you: a legacy of clean, fresh water.