Guest Contributor | Mar 20, 2018 | 0
Water conference on reuse talks about the stark realities of limited water
A conference in Windhoek this week on the technical and functional aspect of water recycling, grabbed the attention of all those who realise that Namibia is always on a knife’s edge when it comes to water. And this general scarcity of the life-sustaining substance does not only affect the desert, about one third of the country, it applies just as much to the entire rest of our territory.
A quick glance at the Atlas of Namibia shows that only the eastern Caprivi, over the long-term, has the hope of regularly receiving more than 600mm rain per year. By world standards, this is very low indeed.
Experimenting with various water reclamation technologies started in the early sixties when frequent droughts made the powers to be realised, Windhoek can not grow without some form of water augmentation. This eventually lead to what is today known as the Goreangab Water Reclamation Plant. This water treatment facility used to be far outside the city but over the past decade, new suburbs have sprung up all around the Goreangab dam, hiding the fact that it is basically a very large sewage treatment plant. Since the first attempts at reclaiming effluent water started so long ago, it has created a hub of expertise and experts at the City of Windhoek, and this entity is rightly regarded as a world authority on water reclaiming, recycling and reuse.
For those unfamiliar with our local urban water reticulation system, about one third of every drop that flows through your tap, has followed that route at least once before. Some drops have followed that route many thousands of times over the past fifty years as they got recycled again and again. And despite the somewhat obnoxious notion of drinking recycled waste water, the City of Windhoek still boasts one of the cleanest water records, not only in Africa, but anywhere in the world.
In short, we take water serious. Generations of Namibians have grown up being taught never to waste water. This has created a rather unique subculture that cuts across almost all other cultural divisions and forces us into one organism of which all the constituent elements realise they are all equally dependent on water.
The International Water Association conference on water reuse, attended by around 400 experts from across the globe, shows that there are many other places where water also is a scarce commodity. Water reuse falls mostly in the ambit of local authorities and this is therefore typically the sphere within which this competence is found. But, in contrast to many other countries, Namibia almost in its entirety is classified as arid. The implication is that whereas many other countries have dry zones or arid regions, these typically also have very wet regions offsetting the impact of the adjacent arid regions. With us, the whole territory is arid so everything we do or plan to mitigate the scarcity of water, applies to a very large extent to the entire country.
This puts the City of Windhoek in a very unique position to provide expertise to other centres of development where inevitably, the demands from a growing human population, eventually outstrip the available water resources. In the north we rectify this by bringing water across not insignificant distances from source, for example, Ruacana, to point of demand, notably the Oshakati Ondangwa Ongwediva complex.
It is ironic that this area also suffers regular flooding, but it only takes a common sense observation, to see that this complex of development will eventually become water stressed.
We certainly have the technology to tap more water from deep underground resources, or from the ocean, but this extraction requires energy and the amount of energy determines the cost of that water. Needless to say, engineered water is far too expensive to use for irrigation, hence it is only used as potable water for households, and a little for animal husbandry. Therefore, reuse becomes a key concept in both supply and cost.
It is one consolation that the growth centres in the rest of Namibia have access to all the expertise they need in the person of the City of Windhoek. When populations in these localities eventually outgrow their available water supply, more and more of them will have to follow the reuse route. This makes economic sense as reuse implies that a large percentage of the available water is already in the reticulation system, and must only be “washed” to make it available again. I know many people do not particularly like the idea, but the fundamental aspect is that this water is much cheaper than having to pump new water. This is also demonstrated by the fact that the cost of Windhoek’s water is fully absorbed into the city’s economic system. We are not nearly affected as much by cost, as by availability.