The increasing scarcity and expense of fossil fuels that industrial agriculture depends upon for fertilisers and production, examined against the waste of nutrients produced by humans, clearly represents another open loop system that must be closed.
Instead of simultaneously polluting watercourses and oceans by wasting these precious nutrients, we need to use systems that recapture them so that they can again fertilise our food, directly or indirectly. This is the only logical and practical way to close this loop and to begin to shift towards a concerted and truly sustainable water and sanitation management system. The most efficient systems separate nutrients and purify the water through using the lowest possible energy systems.
One way to achieve this on the micro-scale is through the use of composting toilets. These have been condemned as being culturally insensitive or degrading by some local communities, while others have embraced them as contributing tangible benefits to community health and wealth. This compost, commonly termed 'humanure' is safe to use as a balanced and efficient plant nutrient.
So, if we wish to achieve sustainable cities from a hydrological perspective, we need to re-examine not only our abstraction of water from distant sources but more importantly, its treatment once we have polluted the originally pristine product.
Industries also pollute vast amounts of water as part of the manufacturing process. Our huge mining industry has created major point sources of pollution through acid mine drainage, which then is returned to rivers and streams, usually without adequate treatment, spreading the impact.
For a start, mining and industrial effluent must be separated from the general wastewater process. Each large industry and mining company must be obliged to return water to the environment only when it has been purified. By doing so the true ecological and economic cost of water can be calculated and included in the industrial process.
Industrial pollution is presently subsidised by both the public and the state. If products cannot be economically produced by using full cost accounting, then the market will be forced to innovate and create new methods of production.
Most water in South Africa is used by agriculture. This is often wastefully used and polluted. Poorly designed irrigation systems can lose half their water through evaporation and other inefficiencies. Fossil fuel based chemical fertilisers seriously pollute water sources through run-off into rivers and groundwater. It is therefore essential to shift to efficient agricultural systems.
Urban storm water is also a major source of pollutants that must be properly dealt with. One way to do this is to temporarily store this water; direct it through natural or constructed wetlands to polish it and then either return it to watercourses or inject it into the subterranean aquifers for later abstraction, as is successfully done in Australia and elsewhere. It has been found that the most efficient way to clean water is through using natural systems like wetlands, which can also be constructed.
In truth, hosting World Water Day is a symbolic recognition and response to South Africa's water crisis. Yet this road show can assist in focusing the perceptions of not only our leadership, but also of the broader population.
However the real problem with these huge international shindigs is that apart from the extensive talk shops and networking, there is little real practical movement towards implementing the real and needed changes that South Africa - and the many other water scarce nations around the world - really need. We certainly need less talk and more action.
It is also of profound concern that the option of public private partnerships has been accepted under UN auspices and is now being promoted by as a solution to sustainable water use. This is both illogical and runs counter to the public good. It undermines the very concept of water being a human right.
Corporate entities are notoriously uninterested in human rights and are instead focused on profit, yet are quite happy to green-wash their motives. Water, as a major component of the global commons, cannot be permitted to be managed by corporate, profit driven interests but should rather be managed by the state directly, or through local authorities, on behalf of its citizens and residents.
What the world really needs is not a World Water Day, or week or month, but a constant focus on the precarious state of our national - and international - water supplies and sanitation practices. Only a consistent, long-term approach to this challenge will enable us to provide sustainable water supplies to the inhabitants of both urban and rural areas.
Ashton is a writer and researcher working in civil society. Some of his work can be viewed at www.ekogaia.org.