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A friend in need

Cuba was a good friend to South Africa and is now a friend in need.  This is surely the sensible reason why our National Government is opting to spend approximately R65M to hire a group of Cuban Sanitation Engineers. When the West was wringing its hands during the Cold War, Cuba was making friends in the developing world.  This strategy has proven to be a wise investment – certainly with South Africa.  We have benefitted from Cuban military support, medical support and now sanitation support.  The small print here is that the support has been paid for, paid handsomely by our grateful Government. Some South African engineers are feeling chagrined that a tidy sum is being spent on specialized Cuban services that are not really needed.  There is no shortage of design and operational engineers – the shortage is of properly run Municipalities.  Infrastructure and operational investment is currently taking second place to more important priorities, such as, and I hope, housing, education, safety and food security. Sanitation should not be poo pooed though.  A host of studies have shown that life expectancy increases with improved Sanitation (have a look here). Perhaps the Cuban Sanitation Engineers are Municipal Managers in […]

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To the sea, to the sea

“To the sea, to the sea! The white gulls are crying, The wind is blowing, and the white foam is flying. ~ J. R. R. Tolkien To the cellar, the cellar.  The winemaker is crying.  The aerators are blowing and the white wine foam is flying.  ~ A.L.O. Usypoet Wine foams when aerated.  This can be easily seen when next time quaffing a Chateau Gondwana with a straw.  Try blowing through the straw instead of sucking and the results will astound (and make a nice mess!) The reason any water will foam when aerated is usually because of something in the water that reduces the surface tension between the water molecules.  Alcohol and tannins are just such agents.  Their chemical properties are such that they weaken the hydrogen-oxygen water bonds. When a winery waste-water treatment plant foams, this is mostly a sign that a fair amount of wine has been dumped.  Although the biomass in the bioreactor does a good job containing the foam, it has a tipping point.  For this reason, it always makes sense to fit a cover over an aerated winery effluent treatment plant.  (See HWT bioreactors)

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Sewage treatment oh so easy

Single pass sewage treatment is all good and well when septic tank effluent is good enough.  If the ground is water saturated, the septic tank effluent will pond.  The attendant smells are not everyone’s cup of tea.  Should the amount of effluent be more than released from a single home, the resultant ponding can be a health menace. Paying tax and treating sewage are brothers of a sort.  In most instances they are regarded as grudge expenditures.  The lack of economic incentive to spend on sewage treatment is a boon to design engineers.  We want to build a treatment plant that does the job at the lowest price.  Always mindful that “goedkoop is duurkoop” the task at hand is a delicate tight-rope walk. In our latest iteration, the SOG Trickling filter, is an attempt to provide an economic, reliable and functioning solution to ground water pollution.  In a single pass, raw sewage is transformed to clear, odourless, sparkling water.  The trickling SOG filter ticks many boxes.  There is, however, much room for improvement.  For starters the filter takes up space – no free lunch here.  Tannins in the media lower the pH and impart a lager like hue to the […]

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Aeration at a Golf Course

  Dual blower arrangement used for a sewage treatment plant.  The blowers inject air into a distribution manifold, providing aeration to the full volume of the bioreactor. Because air is compressible, the air temperature at the blowers is significantly higher than ambient.  The deeper the bioreactor, the higher the manifold temperature at the blower.  For that reason, stainless steel is preferred as a manifold construction material. For efficient sewage treatment, biomass needs dissolved oxygen.  Transfer efficiency of oxygen from air is a function of  water depth water temperature atmosphearic pressure (which is determined by height above sea-level) oxygen concentration in air (21%) diffuser characteristics manifold characteristics  Heterotrophic bacteria need dissolved oxygen to degrade organic material and nitrifying bacteria need dissolved oxygen to convert ammonia to nitrate.

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Viktor Shauberger (1885 – 1958)

It is tempting to meander down the road of counter-factual, the one less travelled and to ask what would Viktor have to say about the state of the world in 2020.  We know that his contributions, written and in deed, were based on observation.  Hours, days and years of observation.  Observing the behaviour of water,  water cascading, tumbling, erupting, swirling, rotating, sublimating, prostrating and oblating.  Roughly 100 years ago, Viktor Shauberger used his knowledge to demonstrate how a small amount of water could be used to transport much needed timber from inaccessible mountain slopes to a very needy and vanquished populace.  To say his hypothesis hinged on the geometry of the trout would be, well, trite. What he did observe was that a small amount of energy, applied in an elegant and considered fashion can yield impressive results.  On numerous occasions, alone in the Austrian forests, Viktor was privy to the extra-ordinary up-stream flight of trout from one river pool to the next.  With a seemingly effortless swipe of the tail, a full grown hook nose would propel himself, body and soul, out of the water and through the air, landing with a quiet plop in the next pool  – […]

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Time of day

Time of day

Thanks to the recent lock-down and current Alert Level 4, we the public, have, at our disposal, the time of day. Contemplating the origins of life fascinates both scientists and the general public. Understanding the evolutionary history of viruses may shed some light on this interesting topic. To date, no clear explanation for the origin(s) of viruses exists. Viruses may have arisen from mobile genetic elements that gained the ability to move between cells. They may be descendants of previously free-living organisms that adapted a parasitic replication strategy. Perhaps viruses existed before, and led to the evolution of, cellular life. Continuing studies may provide us with clearer answers. Or future studies may reveal that the answer is even murkier than it now appears. With acknowledgement to David R. Wessner, Ph.D. (Dept. of Biology, Davidson College) © 2010 In 2015, quoting from COSMOS, the Science of Everything Today, it’s tempting to think of viruses as mere pests. But “they are not agents of destruction,” Caetano-Anolles says. Life on Earth would look very different without our viral co-inhabitants. “We wouldn’t be here without them,” says James Shapiro, a University of Chicago microbiologist. For example, researchers speculate that more than 100 million years ago a […]

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Lockdown, showdown

The end of April will be a pivotal month in our economy for one important reason.  No salaries for a lot of people. In March there was very little warning that companies were to be subjected to a three week shut-down.  I am willing to bet many regret paying VAT on time.  Add two weeks to the unscheduled three and cash-flow will fly out the window.  The real pain is going to start in May.  Even with scheduled returns to work, the repercussions of the collected cash-flow vacuum are going to pinch hard. The most recent COVID 19 Risk Adjusted Strategy is outlined in https://sacoronavirus.co.za/covid-19-risk-adjusted-strategy/ John Donne said, in 1624, that no man is an island, in fact he wrote a poem to elaborate his idea. Here is the first verse; No man is an island entire of itself; every man is a piece of the continent, a part of the main; if a clod be washed away by the sea, Europe is the less, as well as if a promontory were, as well as any manner of thy friends or of thine own were; any man’s death diminishes me, because I am involved in mankind. And therefore never send to […]

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Lindiwe Sisulu

The new minister of Water and Sanitation is Lindiwe Sisulu. Water and Sanitation at National level shares a platform with Human Settlements. Ms Sisulu has enjoyed an illustrious career (so far).    Previous and current Ministers include; Lindiwe Sisulu 2019 – current Gugile Nkwinti 2018 – 2019 Nomvula Mokonyane: 2014 – 2018 Edna Molewa: 2010 – 2014 BP Sonjica: 2009 – 2010 LB Hendricks: 2006 – 2009 BP Sonjica: 2004 – 2006 Ronald Kasrils: 1999 – 2004 Kader Asmal: 1994 – 1999 The DWS was founded in 1912, although then known as the Department of Irrigation.

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Some water related quotations

The mind is like an iceberg, it floats with one-seventh of its bulk above water.  Sigmund Freud Thousands have lived without love, not one without water.  WH Auden When the well is dry, they know the worth of water.  Benjamin Franklin There’s high, and there’s high, and to get really high – I mean so high that you can walk on the water, that high-that’s where I’m going George Harrison If the risk is low, let it go.  Gareth McConkey The solution to pollution is dilution.  Sherry Rogers

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Flushing toilets using grey water

Flushing toilets using grey water requires some planning and a fair amount of commitment. Enchanting as it sounds, acquiring independence from the municipal water and sewage network is no straightforward task.  There are a host of hoops and hurdles that need to be jumped through and crossed.  Contrary to expectation, it is not all about budget.  Sometimes space constraints are just too, well constraining.   Water treatment takes up space.  In volume, it is also heavy.  These are very real challenges that require some thought and attention.  Flushing toilets using grey water requires more than the flick of a switch. Is Flushing toilets using grey water an option? By way of example I will describe the process whereby we have managed to re-use treated grey water for toilet flushing.  A quick parenthesis here.  Sewage is the sum of black and grey water.  Black water is waste water that has in some way participated in the food production or digestive processes.  That would be dish washing and toilets.  Grey water by contrast is waste water drained from cloths washing, baths, showers and basins. Returning to the grey water treatment example.  Guiding principle number one is keep it simple.  Guiding principle number two […]

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Langelier saturation index for measurement of corrosion

This is Nashua, New Hampshire in 1883.  The town and birth place of Wilfred F. Langelier.  The town was named after an indigenous tribe called the Nashaway.  Nashua is also hometown of the famous photo-copiers, the same copiers that save us money, save time and put us first. The hero of this short blog, was born in 1886.   His first degree was a B.Sc., in chemistry which he obtained from the University of New Hampshire in 1909.  He then went to the University of Illinois, where he earned an M.Sc., in 1911.  For the next half decade he worked in the  Illinois State Water Survey department.  In 1916 he was approached by the Professor of Sanitary Engineering at Berkeley University, California.  It was at this famous West Coast institution that Wilfred, soon to be Professor Langelier, would spend the rest of his working life. Today his work is widely known via the Langelier saturation index for the measurement of corrosive potential of potable water in pipes and plumbing.  This seminal contribution was first published in the  1936 edition of the Journal of the American Water Works Association. What is the Langelier saturation index for measurement of corrosion? The Langelier Index is […]

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Flushing toilets using bottled water

Seriously, flushing toilets using bottled water??  How insane is that.   A rhetorical, indignant question/statement/judgement from Bart’s sister, Lisa Simpson. For many years the Coriolis effect was the almost only and very singular reason for watching the flush in a toilet bowl.  They say (Gary Larsen knows who they are) that water drains away in a clock-wise direction in the Southern hemisphere and anti-clockwise in the Northern hemisphere.  For many, watching water drain from a toilet bowl, bath tub or basin, is an amusing and reflective moment. Flushing toilets using bottled water – who does that? In times of want, the luxury of flushing a toilet with bottled or high quality drinking water is deemed highly extravagant and very wasteful.  It is the insulting liquid equivalent of “let them eat cake”. With the prolonged drought in Cape Town, most non-cake eating citizens are using alternative water sources for flushing their toilets.  The low hanging fruit is abstinence during the mellow stage.  Thereafter some sort of big gun is required and this comes in various forms, including shower water, rain water, well-point water, bore-hole water or treated water.  Whatever the source, the emergent zeitgeist is –  use your water twice . And it […]

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Gugile Nkwinti

A warm welcome to our new and suitably qualified Minister of Water Affairs and Sanitation, Mr Gugile Nkwinti. Gauging from media accounts, it appears that Mr Nkwinti has inherited a very troubled and financially unstable department. This might be an unfair reflection and let’s hope that the new incumbent enthuses vitality and professionalism into the much maligned DWS. Our experiences with DWS have usually been quite positive.  Typically representatives from DWS are informed of a new project at the planning stage.  For waste-water treatment plants, our modus operandi is to apply for a General Authorization.  The application and registration process is usually quite quick.  Granting of the Authorization sometimes seems a bit open ended.

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Free potable water from the Antarctic

Magnificent ice berg view from the Antarctic.  Once again the peculiar nature of water is revealed.  Two strange properties leap to mind.  When water freezes, it expands. And with expansion comes an increase in volume with no loss in mass.  The extra volume allows the frozen water, the ice, to become slightly buoyant – in other words ice floats in water. A second strange freezing property of water is that as the molecules re-align themselves, dissolved ions are pushed aside and expelled.  In brief, the  ions or salt is no longer welcome and the ice-berg becomes a very large, floating hulk of potable/drinking water. Is free potable water actually free? Well we all know that there is no such thing as a free lunch.  However, luckily for us, the son’s energy is freely available.  With careful and creative harnessing of fossil, wind or solar power, it is possible for large motor driven boats to head south and collect an ice-berg or two.  This leviathan task is presently not economically viable and for the foreseeable future it is unlikely that we will be seeing ice-bergs dipping past the Karbonkle berg. Removal of dissolved salts from the sea water, or any water […]

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In the News Feb 28th 2018

Cabinet Reshuffle_ Gugile Nkwinti inherits a Water Department that may tip SA into chaos _ Daily Maverick

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the world of birds

December 21st 2017 Water tanker seen near Stellenbosch At the moment Level 5 Water restrictions are in place Level 5 water restrictions are in effect until 31 December 2017. Level 6 water restrictions will be implemented from 1 January 2018.

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HTML view

Also known as Olstyn.  Home of Copernicus and located in the north-east part of Poland in the region known as the “Thousand Lakes”. This small city was founded by the Teutonic Knights in the 14th Century. Since that time Olstyn has seen more than it’s fair share of war and plunder.  Situated not too far south and slightly east of Kalingrad, Olstyn is now part of Poland. The sewage treatment plant in the image on the right, serves the city of 175,000  Note the 1950’s technology, the Pasveer ditch.

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Global warming

Global warming, global warning is hidden in language.  The latin word for a stream is rivus.  The latin name of a person sharing a stream is rivalis.  In the 16th century, the word rival started to acquire a competitive meaning.  The 16th century is the era of queen Elizabeth I,  Shakespeare and Martin Luther. And just deserts.  People abandon inhospitable lands, they desert areas of discomfort.  The deserted areas are called deserts.   The latin word to forsake – that is to give up or relinquish, is deserere.  A word very similar to desire, but meaning the polar opposite. There is much debate regarding global warming.  The consensus among scientists is that severe drought and storm events are occurring on far a more regular basis.  These are easily measurable events and accurate data stretches back hundreds of years.  The increasing frequency of severe climate events can be simplistically linked to the thermodynamic rule stating that “hot air rises”.  When hot air rises, due to warming of the earth or sea, the ambient pressure drops and because, to quote another thermodynamic rule, “nature abhors a vacuum”, cooler air moves in to restore balance.  When the rate of temperature increase speeds up relative to […]

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Community sanitation, living longer

Community sanitation, living longer

The really big jump in life expectancy started in the 1860’s.  This is off-course a pretty Euro-centric  postulation.  But as is often said, you cannot manage if you don’t measure.  And measuring is a very left brain, scientific pastime.  Community sanitation, living longer.  The observation was not in any way clear at the time.  The upward trend in life expectancy only became clear many years later.  For countless years, humans have managed to live fairly long – if they survived childhood.  Before the discovery and effective harnessing of anti-biotics,  death by infection far outstripped any other grim contender.  And it was only in the latter half of the Victorian century that medical practitioners, from physicians to mid-wives took serious cognisance of personal hygiene.  Keeping a clean house and clean hands in the hospital was, prior to 1876, almost unheard of.  Surgeons would rank their success and experience on a peer reviewed blood gown stain index. Community sanitation living longer? Indications are that it does.   With the benefit of systematic record keeping, it is as clear as day, that sanitation saves lives.  Anecdotally,  the largest cause of death during the Anglo-boer was was due to sanitation (or lack of sanitation) issues.  […]

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Koch’s Snowflake

Koch’s Snowflake

Niels von Koch was a Swedish Mathematician.  He is well known for being of the first to describe a fractal curve.  His postulation demonstrated that an area bounded by a progression remains constant, yet the linear length of the boundary tends to infinity. In the picture on the left, Koch’s Snowflake has been cut/carved from a wheat field in Wiltshire.  Fractals are useful mathematical tools that describe the scaling effect of large and complicated systems.  A good example is the tree.  Take a large branch from the same tree and on upright examination, the branch resembles the tree.  By taking a smaller branch from the upright branch, the tree is resembled again.  In a similar fashion, the linear and volumetric geometry of a mouse is scaled all the way up to the blue-whale.  What is interesting though in the mammal analogy is that the metabolic rate of cellular activity does not increase in a linear fashion.  There is a distinct energetic saving in the larger species.  This law allows larger mammals to live longer than smaller mammals. Research at the Sante Fe institute, has shown that service delivery, as a measurable unit per inhabitant, is higher in cities than in small communities. […]

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Running out of water – Part 1

Without much debate, one of the hardest pills to swallow, is having no water with which to flush the loo.  If this should be your lot when the taps run dry, a compost toilet could save the day.  Although a squeamish subject, a dry spot for relief is very natural.  Before the intervention of the Victorian Monkey Closet, keeping it dry was the order of the day.  A bit like the QWERTY keyboard, the flush loo has become a feature of modern life.  Is it really necessary to use bottled drinking water to dispatch an unhallowed parcel?  And like the QWERTY keyboard, an arbitrary flush convention was adopted that persists, unchallenged and in many societies even revered. Could it be different?  Is it possible to live without a QWERTY keyboard – or a flushing loo.  Perhaps it is – for both.  As with so many conventions, attitude is the glue that coalesces the signatories.  And like most conventions, a sell-by date is embedded in the small print.

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Enzymes

A simple analogy that is sometimes used to describe the activity of enzymes involves biltong.  Most know that to eat a stick of dried, but not too dry kudu biltong is a laborious process.  It requires some wrenching and a lot of chewing.  Slicing the biltong in a cutting machine will produce a packet of biltong slithers.  In a bet that cannot be lost, the sliced biltong can be eaten more quickly than the biltong stick.  And that is what an enzyme does, it slices up large carbohydrates.  In brackets, enzymes do a whole lot more than that, but from a waste water engineering perspective, the biltong analogy is useful and descriptive. Many waste water treatment plants used bacteria to remove dissolved organic material found in the polluted water.  The cell structure of bacteria is defined as prokaryotic and this means that a bacterial cell has no nucleus.  DNA, ribosomes, enzymes and bits of substrate float around in an intercellular liquid cytoplasm.  Substrate in this case would be the dissolved organic compounds present in the waste water. A thin membrane serves to hold the cell in shape.  By some clever alchemy, the bacterial cell manages to convert available substrate into […]

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Flowforms

It is difficult to explain how flow forms assist in treatment of water.  There is an obvious pattern of counter current oscillation that can draw and absorb dissolved oxygen from the air.  From that point of view, flow forms can be seen as an aeration device.  There are anecdotal explanations stating that flow forms revitalize water and provide a stimulus for biological growth.  For your average water engineer, the function of a flow form cannot be measured with an instrument or analysed in a laboratory.  There is, however, a usefulness that can best be described by way of analogy.  It’s called the rope analogy. We all know that rope is constituted from strands intertwined in a circular or braided pattern.  The patterning gives the rope extra strength by employing the principle that the whole is greater than the sum of the parts.  Extra strength is attained via the inter twine friction force that increases as a rope is stretched under tension.  When a length of rope is relaxed and is lying on the ground, gently rolling of the rope will result in particles from the ground getting pinched between the strands. Continual rolling action will enmesh the particles, which could […]

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Paint splash

High speed capture of paint rebound.  In this briefest instance, a small weight was dropped into a paint solution.  The resultant recoil of the paint mix was recorded 5 milliseconds after impact.  To catch the moment, a camera needs to be able to film at more than 200 frames per second. Turning the clock back, we all have fond memories of Millikan’s oil drop experiment.  In this extra-ordinary work, Millikan and his colleague Harvey Fletcher, calculated the electrical charge of a single electron.  Because an electron is very small, the corresponding electrical charge is also very small.  Back in 1909, high speed photography was not in wide use and our two scientists had to use a microscope and stop watch arrangement to measure the speed of oil drops falling between to electrically charged plates.

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Title page editor

Why water It is the most satisfying feeling in the world to clean dirty water. Often this is no easy process and sometimes it takes a long time to get it right. We enjoy the challenge and enjoy our work. That the product of our efforts helps keep the environment cleaner is a bonus. HWT is a water services provider. The company was founded in 1994 and since then, has successfully designed, built and commissioned in excess of 100 treatment plants. In general, the treatment plants are fully automated, requiring minimal operator intervention. Our design philosophy consistently favours process and cost efficiency.  Typical projects include treatment of; • domestic sewage • industrial effluent • food processing waste water • winery and cellar effluent • potable/drinking water Additionally, HWT offers process maintenance and effluent management solutions.

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Irving Langmuir

Too much water, too little water, water too dirty.   That’s the challenge water engineers face in South Africa.  And not just in South Africa.  The triangle of extremes is also applicable in the USA.  One engineer who did his bit was Irving Langmuir.  I am sure everyone knows about maritime Langmuir circulations. The presence of these circulations are revealed by the streaky patterns of foam or debris visible in the sea or a lake on a windy day.  The formation of these circulations is dependent on steady and sufficient wind velocity.  The circulations can be likened to sub-surface, long tubes running in the direction of the wind.  Each tube rotates in a direction opposite to its neighbour, thus creating clefts of upwelling and submersion currents at the tubular boundaries. Langmuir circulation is an important mechanism for ingress of dissolved oxygen into a water body. In the diagram below, the formation of Langmuir circulations is clearly visible

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R. Hooke, Fellow of the Royal Society

Observ. XVIII.  Of the Schematisme or Texture of Cork, and of the Cells and Pores of some other such frothy bodies. I took a good clear piece of Cork, and with a Pen-knife sharpen’d as keen as a Razor, I cut a piece of it off, and thereby left the surface of it exceedingly smooth, then examining it very diligently with a Microscope, me thought I could perceive it to appear a little porous; but I could not so plainly distinguish them, as to be sure that they were pores, much less what Figure they were of:  But judging from the lightness and yielding quality of the Cork, that certainly the texture could not be so curious. So wrote Robert Hooke in his ground breaking 1665 publication of Micrographia.   Because these small pores looked monastic, Hooke labelled them cells.  Today Hooke is credited with naming the building blocks of all life – a cell. And talking of cell, there are two distinct types – those with a nucleus and those without.  Bacteria fall into the category of organisms (or domain) that do not have a nucleus.  For these nucleuslessness organisms, all the components of respiration and replication are loosely lumped within […]

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Grey water – shades of grey matter

When water is scarce, our gardens take strain.  One of the ways to stave off parched lawn syndrome is diversion of grey water to the thirsty garden parts.  Just in case there is some confusion, grey water is any used water that has not been part of the food preparing or digesting process.  It is mostly clean, in fact very clean because it would contain quite abit of soap, shampoo, toothpaste and anything else that lathers.  There will also be a small amount of organic material in the form of skin cells and even smaller amounts of bodily extrudate. For life in the soil, grey water is a mixed blessing.  Although the liquid component is very welcome, the attendant du parfum toilette presents a puzzling conundrum.   In grey water there is very little organic material that is of use to microbes living in the soil.  Although there are some nutrients in the grey water and phosphorous is one of these, the quantities far exceed the demand.  Soap is the ticking time bomb.  Most soaps contain active ingredients that act as solvents in water.    When soap loses its active functionality it very quickly dissolves and in so doing increases the baseline […]

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Teralitre – terribly large number

Total storage capacity of all the public dams in the Western Cape adds up to 890,000 megalitres.  That big number is almost 1 teralitre.  As of October 17th, the amount of water stored in the same dams was 0.56 teralitres – roughly 62% full.  For the Cape in April, this would be a comfortable position.  Nearing the end of October, the picture is slightly different.  The rains are pretty well over. The estimated population of greater Cape Town is 3.7 million.  Assuming each person uses 100 litres per day for eating and hygiene purposes, the volume of water required to sustain that same population for one year is 0.14 teralitres.  Comparing this demand to the available resource, it seems that we are home and dandy.  The dams have 0.56 teralitres – enough water to last 4 years. However, the 100 litre per person per day allowance does not include water used for irrigation, water used by industry and agriculture. Adding to the head-ache of our suffering city fathers is the state of the dams.  As the levels drop, the ambient water temperatures start to rise.  This can adversely effect water quality.  Biological activity climbs with increase in temperature.  Dissolved oxygen […]

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Advanced Oxygenation Process

  Bill Bryson once famously said that the thing about space is that it is, well, spacious.  And that it is.  In amongst all that space are a surprisingly large number of hydrogen and helium atoms. In addition there is also electromagnetic radiation, magnetic fields and cosmic rays.  During the early part of the 1960’s, when the Vietnam war was starting to heat up, scientists discovered the presence of OH (hydroxyl) radicals in a Supernova.  11,000 light years away is the constellation of Cassiopeia and it was here that the OH radicals were discovered.  A supernova is an astronomical event that occurs during the last stellar evolutionary stages of a massive star’s life, whose dramatic and catastrophic destruction is marked by one final titanic explosion.  For obvious reasons, supernova have enthralled astronomers and physicists alike.  There is a supernatural quality to supernova that in their understanding, there might exist a glimpse into the understanding of the cosmos. Back on earth, hydroxyl radicals are associated with the excited state of system, which is a quantum state – and here too we run into comprehension issues.  This is the turf of complicated physics and an unlikely water related reading matter.  Except though, the […]

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Algal bloom, Shandong style

This is a pretty impressive site. Green algae rules the beach – The seas off China have been hit by their largest ever growth of algae, with vast waves of growth turning the Yellow Sea, green.  For the last 6 years, large quantities of non-poisonous green seaweed has thrived near Qingdao in northeast China’s Shandong province. The usual culprits for the massive surge in algal growth include warm days with plenty of sunlight and meaningful amounts of detergents industrial and sewage spillage Apart from a high squeam factor, the green seaweed is not harmful.  It will only be a matter of time before inventive entrepreneurs harvest the bounty for financial gain.  Off course harvesting is not really addressing the cause, but it will introduce a useful remedy. Reduction in nutrient spillage will curtail the growth significantly.  To remove the last vestiges will be tricky – a problem that is found throughout the world.  At the moment the list of cost effective algal control methods is a very short one.  The old adage prevention is better than cure holds true for algal growth, but in an industrialized world, prevention is sometimes a price too high to pay. And talking of short lists, there […]

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Chicken and Chips, the start of sewage treatment

A little known outcome of the Great Exhibition at Hyde Park held from 1 May to 15 October 1851 was the gestation and birth of sewage treatment.  At the Exhibition, well known sanitation engineer and potter, George Jennings installed his Monkey Closets in the Retiring Rooms of The Crystal Palace. This was, for the Victorian public, their 1st exposure to a communal convenience.  And it caused quite a stir. During the exhibition, 827,280 visitors paid one penny to use them and for that penny they got a clean seat, a towel, a comb and a shoe shine. “To spend a penny” became a euphemism for using the toilet. When the exhibition ended and moved to Sydenham, the toilets were to be closed down. However, Jennings persuaded the organisers to keep them open, and the toilet went on to earn over £1,000 a year. Jennings said that “the civilisation of a people can be measured by their domestic and sanitary appliances”. Little did the public know that their appetite for home installed Monkey Closets would create a cascade of problems.  At the time, waste water of any description, was simply thrown into the street.  However, water was needed to rinse and clean the […]

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Kader Asmal

Abdul Kader Asmal, politician, lawyer and academic, born 8 October 1934; died 22 June 2011 For sheer energy, nobody in South Africa’s post-1994, non-racial cabinets could match Kader Asmal, who has died aged 76 following a heart attack. He was not known as “the Bee” for nothing. The first to feel his sting after he was given the relatively junior portfolio of water affairs and forestry in 1994 were his own civil servants, one of whom said, “He terrorised us into activity.” But he mixed this with persuasive eloquence, somehow managing to secure the support of Afrikaner civil servants from the old order who, in political defeat, surprisingly saw themselves resurrected as part of a “winning water team”. Kader’s dynamism was limitless, and his flair for publicity came to the fore after President Nelson Mandela, to whom he was close both personally and through their African National Congress (ANC) work, appointed him to the cabinet. Envious colleagues complained they could not open a newspaper without seeing Kader turning on a tap delivering clean drinking water to remote rural black communities. Later, he was given some political hot potatoes: chairing the cabinet’s conventional arms control committee, concerned with ruling on the […]

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Dwindling water supplies in the Western Cape

  In April 2016, the combined dam levels in the Western Cape stood at around 31% of full capacity.  This is the lowest level in 6 years.  Water demand in the Western Cape has most likely not dropped and it can be expected that water will become scarcer towards the end of the year. Fortunately, the Cape is a winter rainfall area and the demand for irrigation water will plummet.  It is odd to think that all the parks and gardens of the Cape’s cities are supplied with treated water.  This is mountain water that is treated in world class facilities transforming mostly lager looking tannin rich mountain water into crystal clear bottled water.  Regardless of the amount of water available in our dams, our gardens and parks are irrigated with bottled water. Fruit farms use untreated, lager like water for irrigation of crops.  Should this not be done in the cities for irrigation of parks and gardens, for soccer and rugby fields?  Would that it were so easy.  The tannin lager water from the mountains tends to have a low pH and could cause corrosion.  True, but modern pipes are frequently fabricated from HDPE.  A substance that is robust, […]

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Moeller PLC

Moeller PLC

  HWT has been using the Moeller Easy PLC since 1998.  Since then the EASY has hardly changed although functionality and robustness have inevitably improved.  The EASY is a compact PLC that can be programmed in-situ using the straightforward display screen via PC and comms cable using EASY Software From July 2011, Moeller and Eaton, two of the longest-established and most respected names in the electrical sector, come together as one Eaton, a global organisation delivering solutions which support their customers in running systems more productively and more cost-effectively.  

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The Crimea, then and now

The Roll Call, or Calling the Roll after an engagement, Crimea.  Painted in 1874 by Elizabeth Thompson some 20 years after the event.  For this evocative image, the artist used healthy models.  To the British public this was a depiction of personal horror.  Nothing heroic about the bedraggled survivors.  The title itself is a powerful messenger that mutely honours the dead and lost. A big name in the Crimean war was Florence Nightingale.  Famously Florence pioneered and established professional nursing practice.  Of her various and for us today, obvious methods, included ventilation in the sick wards and provision of clean drinking water.  On reflection it is difficult to imagine that the wounded and sick would be offered anything but clean water. The Roll Call is hanging pride of place in the Royal Collection, a priceless sampling of artwork spread in 13 Royal venues.  

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March Days

This is a poem that John Masefield wrote in 1902. ‘Cargoes’ Quinquireme of Nineveh from distant Ophir, Rowing home to haven in sunny Palestine, With a cargo of ivory, And apes and peacocks, Sandalwood, cedarwood, and sweet white wine. Stately Spanish galleon coming from the Isthmus, Dipping through the Tropics by the palm-green shores, With a cargo of diamonds, Emeralds, amethysts, Topazes, and cinnamon, and gold moidores. Dirty British coaster with a salt-caked smoke stack, Butting through the Channel in the mad March days, With a cargo of Tyne coal, Road-rails, pig-lead, Firewood, iron-ware, and cheap tin trays. John Masefield One of the big spirits at the CSIR was a man named Andre Gerber. In the heady days before 1994, Andre Gerber was the head of the CSIR’s Watertek Division.  Here is one of Andre’s astute observations. In South Africa there is either too much water, too little water or the water is too dirty. With this in mind it is clear that South African Engineers are faced with water issue challenges.  It is not so much the technical challenges as the budgetary challenges – and that is what drives innovation.  It is not for nothing that they say – ‘n […]

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Melanie Schultz van Haegen

Sewage treatment in the Netherlands is administered by the Ministry of Infrastructure and Environment.  Incumbent minister (2016) is Melanie Schultz van Haegen and here is her mission statement.. It is my goal to make The Netherlands fit for the future: our infrastructure must enable new economic dynamism and people and goods must quickly and easily reach their destination. Therefore I invest in the missing links in our highway network and in high quality inland water and rail transport. But I also invest in innovation, because I believe The Netherlands is well equipped to be a global leader in mobility and logistics.’ ‘Making The Netherlands fit for the future also means less and better spatial regulation. The new Environmental Planning Act enables development and local initiatives by citizens and entrepreneurs, while at the same time safeguarding a high quality environment.’ ‘The Netherlands is one of the safest river deltas in the world. Yet we remain vulnerable because there is so much to protect. Making our delta fit for the future therefore means investing in dry feet and living safely with water, to prevent new water-related disasters. Internationally I also advocate a preventive approach to water-related issues. Dutch knowledge, skills and expertise play a crucial […]

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Boxing day 2015

This is St Stephen, or at least the visual interpretation of Italian Renaissance painter Carlo Crivelli.  St Stephens day is all about charity, giving to the poor and caring for the uncared.  St Stephen himself was most likely Greek speaking and Jewish. The little we know of his personal life is thanks to a brief mentioning in the new testament.  The feast of Stephen is associated with Boxing day, the day after Christmas when staff and servants receive small gifts from their employers.  These gifts were predictably proffered in boxes. More recently (100 odd years ago), these German soldiers spent boxing day playing the piano, making breakfast and keeping one eye on the other side.

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Its all about the light – algal blooms

Green algae is a plant that sustains itself from carbon dioxide, sunlight and nutrients (primarily nitrogen and importantly phosphorous).  In marvellous alchemy algae (and all other plants) convert light energy into chemical energy.  The same chemical energy sustains the algae’s growth and activity.  The real wizards in the process are proteins in the plant which absorb light energy.  Proteins are long chain molecules, requiring nutrients. For an algal bloom to occur there needs to be excessive amounts of nutrients and light energy. In a dam, ingression of nutrients occurs from vegetation that grows in and around the water.  Grass cuttings, leaves and sticks find their way into the dam, adding to the nutrient load. So at any time, a dam will have lots of nutrients.  When a heat wave occurs, there is more sunlight, with more light energy.  When this happens algal growth and activity is accelerated. To prevent algal growth, only one of the major ingredients needs to be removed.  This is however rather difficult.

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Swartland ENGEN One Stop

SHEQ rules OK The ENGEN One Stop bioreactor program is proceeding smoothly.  In the final stages of the installation, the sewage pumps are lowered into the manhole. By the end of 2015, Engen will have upgraded the effluent treatment facilities at 7 retail sites.  These sites are situated at some distance from local sewage treatment plants and as such on site effluent treatment is required.  The principal objective of this exercise has been to ensure a compliant treated effluent quality with minimal environmental impact.  Over and above, Engen has chosen to install treatment plants that are robust, unobtrusive and reliable. Left unattended, liquid effluent is a health hazard that can pollute water-courses, cause odours and contravene legal compliance requirements.  Typically Engen One Stop sites use water in the following ways; Wash basins and toilets Kitchen sinks and dishwashers Floor and counter cleaning Leaks from geysers and irrigation networks The used water is termed effluent and in general all effluent is discharged from the One Stop Sites via a single pipe.  For obvious reasons, this type of effluent cannot be discharged straight to the environment and some form of management is required.   As the effluent contains a significant portion of inert […]

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Civil Technologist with water experience (July 2015)

Civil Technologist with water experience (July 2015)
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SOG filtration used for treatment of Winery Effluent

Up to 10 kilolitres per day of winery effluent can be treated in the SOG trickling filter installed at Uva Mira. Innovative technology requiring no pumping or process control.  This site allows gravity flow throughout the treatment process.     Quick start-up.  Within 2 weeks COD reduction to less than 150 mg/l.

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SHEQ Rules – then and now

  Changing light bulbs on the Eiffel Tower, 1937.  Note the shoes, no safety harness, no gloves, no helmet – but nice jacket and could that be a neck-tie? In the USA, being a fisherman is statistically the most dangerous job.  More fisherman die per 10,000 people than construction workers, airline pilots and miners put together.   At the other end of the scale truck drivers top the charts by sheer volume.  

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Ebrahim Sartarien

This is Ebrahim Sartarien – long time water treatment plant operator at Klawer Valley, the restricted military area above Simonstown.  Ebrahim made an interesting observation.  Wearing a jersey in mid-November, he explained that the water treatment process has become far trickier now than in previous times.  Why might this be?  Water quality, he went on to say, was far more regular in the old days. In the Cape, mountain water tends to be slightly acidic and has a distinctive discolouration.  Because the colour in the mountain water is insoluble, it won’t be removed by simple filtration.  For example and in a similar fashion, tea won’t revert to clear tap water by pumping it through a pool filter.  Treatment of this type of water is most effective by using a flocculation method.  One thing all operators know is that the flocculation dosage rate is a finicky measurement.  Too little and there is no reaction, too much and there is no reaction.  The dose rate has to be very accurate to get best results. In the old days, variation in mountain water quality used to be distinctly seasonal.  Once a day Ebrahim would do a flocculation test to determine the best chemical […]

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Why do we bother Fawlty

In the last 20 years we have noticed a number of developments in the wine effluent treatment business.  Companies come and go, technologies are tested, touted and taper away.  For some time we have been wondering why is winery effluent so difficult to treat?  It is after all mostly biodegradable.  Sure there are some chemicals that come down with the effluent, but by and large the modern winemaker is an extremely competent and environmentally conscious individual.  For these two reasons it is relatively easy to see the bright side of winery effluent treatment. By way of analogy and after building and operating more than 30 winery effluent treatment plants, my observations are as follows. Imagine a restaurant in a small suburb in the village – Stellenbosch is a good example.  The restaurant has a small menu.  Each working night a body of clientele come along and most nights all the food prepared is enjoyed by happy customers.  The restaurant remains successful in that it is not wasting food.  The restaurateur can gauge his food purchases with the amount of meals sold.  The two match quite evenly. Now imagine another restaurant, also in Stellenbosch.  Here the restaurateur is adventurous.  He provides […]

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Be nice to bacteria

Waste water treatment is not quite the same as treatment of the sick.  For humans a visit to the doctor is usually prompted by one, perhaps two presenting complaints.  After diagnosis, the Doctor will look at the patient and say in a grave voice – you have small pox, but you will be fine.  Just take this course of anti-biotics and get plenty of rest.  For waste water treatment the list of presenting complaints is often a big list.  For instance the presenting complaint might be prompted by an irate neighbour complaining of smells or a Municipality charging huge surcharges. On analysis the waste water can be suffering from low pH, high conductivity, high COD and high turbidity.  In almost all cases there will not be a single cure for each of these conditions.  Each of these parameters will require it’s own set of treatment processes.  If biological treatment is deemed the appropriate route, some of the out of specification parameters will have to be addressed first.  So here we have a patient who not only has small pox, but also has black eye, broken ribs a nasty cold and a bout of shingles. One of the big challenges in […]

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Space Age Water

Municipalities the world over provide utility services such as water and sanitation, electricity, road repairs and much much more.  The adequacy of the service is very variable and has much to do with the vociferousness of the rate paying public.  Adequate service is not good enough in a space station.  Here the municipality has to provide a top-notch service.  The client base is small and the stakes are high.  A small slip up can cause extreme discomfort.   Lets look at water.  On the International Space Station roughly 93% of all water is recycled for re-use.  Water vapour,  grey water, black water – all water is collected, treated and re-used for any activity, personal or otherwise requiring water. 93%  is impressive for several reasons.  It is a major saving in carting around water with attendant logistical and lift-off costs.  It is also impressive that in a zero gravity environment, almost every drop of water is collected at a central point for recycling.  It is said that nature abhors a vacuum.  At the ISS, in an extremely unnatural environment, the vacuum is used extensively.  The humble toilet works on a vacuum principle – and thank goodness for that. Treatment of water […]

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Abbey Mills

The recording studio in Abbey Lane is well known thanks to the Beatles and more recently One Direction. What is perhaps not as well known is the Abbey Mills sewage pump station. Located near the studio of the same name, the pump station was built in extravagant Victorian style in 1865. The pump station lifted accumulated sewage 40 feet, enough to send it to the Thames, downstream of London.  Before the pump station was built, the changing tidal level of the Thames River would flush sewage back into streets.  Up until the mid 1800’s, London sewage was drained straight to the Thames.  There is nothing like an outbreak of cholera and a heat wave induced stench to get action from politicians.  In record time large amounts of public purse were diverted to the construction of sewers.  The workmanship of the tunnels and shafts have stood the test of time.  Much of the original network is in use today. Initially Abbey Mills was a coal powered pump station.  There were 8 steam driven pump sets with a combined delivery of 28 kilolitres per minute – a substantial flow even by today’s standards.  A more modern facility was built in the 1970’s although Abbey Mills […]

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Water everywhere but not a drop to drink

Almost 100 years ago to the day, a dark cloud descended on Europe and indeed on the World. For many at the time, the possibility of war seemed remote. It was generally believed that the “civilized” and “scientific” nations would not risk starting a conflagration of unprecedented proportions. In spite of the doubts, war did start and perhaps because of the technological advances, stalemate was quickly reached. Within 6 months the trench warfare, images with which we are so familiar had begun – a way of life (and death) for many millions that was to only end in November 1918. It might have been Napolean who said that an army marches on its stomach. Not sure who said anything clever about water but everyone knows a thirsty army cannot survive for very long. The war in the trenches of Flanders presented all manner of water supply challenges. Ground water was often available in abundance, especially when water tables were high. As a drinking water source, ground water was at best useful for washing. Mostly the ground water was heavily contaminated by wastes of all descriptions, both chemical and organic. For eating and drinking, water had to be carried to the […]

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