Cape Town’s changing water sources

Cape Town’s Changing Water Sources

Cape Town and the Western Cape as a whole had always been known as a soft water area, so why are many residents experiencing problems with scale build up in their pipe work? This normally occurs when an area has mineral rich hard water?

A major factor is the popularity of the Cape over the last decade causing more and more people from other provinces and relocate in the greater environs of Cape Town.  This growth in the population base has led to an increased demand for basic necessities from the municipalities, such as the availability of a clean and safe water supply.  

Climate change

Unfortunately the world is going through a period of climate change which highlights certain alarming facts relating to South Africa.  For instance, in 2015 Cape Town recorded its lowest annual rainfall since 1904 and in the same year recorded its highest temperature at 42°C for the last 100 years! 2017/18 also brought the worst drought in decades for the Western Cape and experts are predicting a worldwide average rise in temperature of between 2-4°C (this does not sound catastrophic in perspective the last time that the earth was 5°C cooler was in the last Ice Age) This therefore relates to less surface water being available for both human consumption, agriculture and industrial usage so the Western Cape has an increased demand with a shrinking supply base. How can they address the problem?

Luckily the Western Cape three underground aquifers of which one is possibly the largest worldwide with a potential yield of up to 30million litres per day      

Although more expensive than recovering from a surface asset (such as a dam) the availability of these alternative water sources is essential to economic growth for the province, however this route of supply does come with complications that need to be addressed.

Most surface water sources are acidic due to acid rain with a typical pH of 4 (clean rain typically 5-5.5) which would cause the surface source water to be classed as soft.

Acid rain

However the acid rain has a different effect on ground water. As the acid rain permeates the different levels of soils and rock layers it leeches certain alkaline minerals from the layers neutral state. The Western Cape and indeed a large percentage of South Africa are made up of beds of sedimentary rocks, mainly Limestone, Dolomite and Gypsum. Therefore as the acid laden water travels through the different strata’s the main minerals that it collects is Calcium and Magnesium. This now mineral rich water will continue to soak through the layers absorbing more and more alkaline minerals until it reached an impervious layer of rock.

Hard water

More and more the water circulating through Cape Town’s 10,000km plus water supply network is becoming “harder” (Alkaline enriched) as the percentage of water recovered from sub terrain sources increases. Is this a problem? Alkaline water is proven to be more healthy and “soft” (acidic) water can lead to chemical and electrolytic corrosion in metallic pipes and fittings? However the greater percentage of Calcium and Magnesium present in source water the greater the incidences of scale encrustation become.

Scale

Scale is basically Calcium and Magnesium ions which have come out of solution and via electrical attraction bond together with other suspended solids to form encrustations which form on the surfaces of pipework, fixtures and fitting. Scale is known as the “silent” killer as it is unseen until either the pressure and flow drops drastically or there is a pipe fracture or fitting failure. Scale in a building pipework system can be extremely expensive, both through the constant maintenance required and inefficiencies (1mm scale)

Build-up on a heat exchange surface can equate to a 15% loss in heating efficiency while 1mm of scale build-up on the inside surface of a hot water pipe will absorb heat from the water equating to a further 10% loss in efficiency.

What if we could enjoy all the benefits of “hard” mineral rich water without the associated problem of scale?

Luckily technology has been advancing steadily in the water treatment industry and the new method of electronic Impulse treatment based on the natural process of electrophoresis now offers a way to combat scale while not affecting the pH of the water or removing the healthy calcium and magnesium from the water flow.

Electronic impulse systems

The electronic impulse systems manipulate the structure of the calcium and magnesium ions from a complex three dimensional snowflake shape crystal prone to join together via electrical attraction and form encrustations into a simple cylindrical shaped mono crystal with only a positive and negative end, therefore producing long strings which are carried away with the water flow. The by-product of this process, CO² and H²O will then join together to form carbonic acid (H²CO³) which will gradually and safely break down the existing encrustations until the system is clear of scale. Once there are no more scale encrustation to dissolve the carbonic acid will coat any metallic surfaces with a protective metal carbonate layer to act against further corrosion.

With the scale build-ups removed from the pipe work system you will regain your original pressure, flow rate and ensure that the system operates at optimum energy efficiency. You will also be rewarded with Health benefits as the scale beds act as breeding grounds for bacteria, micro-organisms and pseudomonas (such as Legionaries disease) and once removed these potentially dangerous contaminates will wash through the system before they get a chance to breed and spore.

For a more in-depth explanation on the electronic Impulse Technology anti-scale system and how it works please visit www.amanzirms.co.za/cwt-technology/ or contact Chris Davey at either mwchrisd@mweb.co.za or my mobile 084 690 2644