Water Security includes Sanitation – the ability to maintain freshwater quality so that it can be safely used for human purposes. This week we consider important issues affecting sanitation. (More)
In developed countries, we take for granted access to clean water. We expect that water in the tap is drinkable (though many Americans have turned away from tap water in favor of bottled water). We take for granted that we can safely bathe, that our showers will not sicken us with disease or toxins. We understand that our waste water is properly handled. Our sewage is transported away from our habitats whether home or place of work to processing centers where it is cleaned to various federal, state and local regulation, and then reintroduced into the environment “somewhere else.” When we cook, wash our dishes, bathe or flush our toilets, we see wastewater disappear and think nothing further of it.
That ability to ignore sanitation is a true luxury. It is a luxury because the vast majority of humans do not share in that facility. It is a luxury for us too, because even a hundred years ago, most Americans did not enjoy this ability. In fact, the need for public sanitation, as an important part of the infrastructure of civilization has been “known” and forgotten many times in history. Name practically any great civilization, and you name a success story in public water supply and sanitation. From the Aztec and Maya, to the civilizations of Mesopotamia, India, China, and Europe, the control of water was essential. What the Romans understood: the importance of hygiene, the importance of public baths, and sewers, of aqueducts and fountains, was largely forgotten in Europe until the Renaissance.
Sanitation: Challenges and Issues
The problems of sanitation are the same everywhere and everywhen: Protecting supplies of freshwater at its source and during distribution, and preventing its contamination from microbes, toxins, feces, dirt, etc. Sanitation is the organized, planned discharge of waste water so that it does not contaminate habitable human spaces or the freshwater needed by people to survive.
There are many issues that affect sanitation at the source of freshwater. For example, is water drawn from an aquifer? The kinds of rocks and sediment that the water passes through before collection in the aquifer determine many of the impurities in the water. If an aquifer is close to a coast, saltwater intrusion can make the aquifer briny.
With rivers and lakes, contamination from organic materials such as rotting vegetation, or animal waste are probable. Particulates such as mud and sand can also affect water purity. Parasites and infectious disease are also possible.
Because water can evaporate, but heavier materials remain behind, over time, contaminants can concentrate in lakes and reservoirs. Agricultural runoff, salt, fuel leaks from shipping, or industrial wastes can build to toxic levels. Bulk trash such as water bottles, paper, tires, lumber can also accumulate.
Often, communities of humans do not reside immediately next to good drinking water. Instead water must be transported to them. The quality and type of transport system can also affect sanitation. For example, in the 1800’s it was common to use wood as pipe for freshwater distribution in cities. Wood rots, and in decay allows earth and other mater to enter the distribution system. It also affects reliability because water is lost where ever the wood pipe has failed. Similar problems exist today with outdated and decaying iron and concrete piping. The use of lead pipes was considered to be a health hazard because of contamination with lead. Even modern distribution systems that use PVC (Poly Vinyl Chloride) pipes have issues with chemical contamination. Bottled water may not be safe because of leaching from the plastic in which it is stored.
The mechanism by which water is stored for later use can also affect water quality. Aside from reservoirs and lakes (already discussed), water storage systems can involve tanks, cisterns and aquifers via the use of Aquifer Storage and Retrieval (ASR). Tanks can corrode or leak, cisterns are often exposed to the elements, and ASR can fall victim to leaching of contaminants from native rock.
Cross usage of water for several purposes can mix contaminants such as human and animal waste, food, and soaps. The use of poor quality vessels such as leaded ceramics, repurposed containers (such as ones for pesticides) can also impact water purity.
The handling and disposal of waste water is a key component of sanitation. Waste water reintroduced into the drinking supply is a significant source of pathogens and pollution. Bathing in a lake or river used for drinking water, runoff from untreated or poorly treated sewage, seepage from septic systems into groundwater, use by domesticated animals, food waste, and trash all contribute to poor water quality.
Water can also contain human introduced impurities. Lime is used as part of water treatment and remains in water distributed to residences. Chlorine, or flouride may be introduced for public health reasons.
Regulation and enforcement
Government regulation determines levels of impurities for drinking water, water treatment and distribution. Poor standards for safe water, or lax or nonexistent enforcement can jeopardize water quality.
War and environmental catastrophe
War and environmental disasters create significant pressures on fresh water and sanitation. Natural disasters such as floods, hurricanes, tsunami, drought, volcanic eruptions, and earthquakes can all seriously disrupt water storage, treatment, and distribution systems. Human caused disaster such as fires, chemical spillage, dam failure, nuclear reactor meltdown are real possibilities. Regional conflict, civil war, or the absence of any government are also significant concerns.
Human attitudes towards water are perhaps the most important factor affecting water sanitation. Many of the examples listed above reflect human values about water. Everything from where water is sourced, what is considered acceptable quality, and how to handle waste are all reflections of cultural norms. For example, we in the west would consider bathing in our drinking water to be repulsive. Yet people in many parts of the world do exactly that. Cultural attitudes about water quality can prevent safe practices for handling of water and waste from being accepted or adequately implemented. If a group of people do not see or understand the relationship between their use of water and the positive and negative outcomes, they are unlikely to alter maladaptive behavior, and are less likely to continue practices that are beneficial.
Next time: Case Study – Guinea Worm Disease
Readers Comments are welcome.