Does it take a genius to predict drought?

Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 23 January 2011

By: Jeremy Westgarth-Taylor – Founder of Water Rhapsody.  Inventor of all the Water Rhapsody Systems.

While the fear of water restrictions work in favour of those of us who are involved in water conservation, it would be preferable for all of us to have smoothed restrictions rather than an all or nothing scenario.  All of us mean the population at large, the municipality, the Department of Environmental Affairs as well as Water Rhapsody. Please let me explain…

Although the upper Steenbras is almost full the majority of this water is stored for electricity power generation

Cycle of drought

Six, seven years or perhaps even eight years may elapse between one and the next season of drought.  These years between drought cycles are winter months in Cape Town of higher than average rainfall, and the reverse in the northern regions of South Africa where we get summer rains. During these years of higher than average rainfall, all thought of the fact that we live in a water poor region of the world, is forgotten.  Forgotten is the notion of drought by the bureaucrats and politicians that run our city.  Drought is a long forgotten figment in the memory of the population at large as well.  Every drought season, virtually a whole new generation needs to be re-educated in our need to use less water, and how to use less of the precious stuff.  We should not forget what was written in biblical times that we have seven years of drought and seven years of plenty.  While some areas north of Cape Town are experiencing floods of the magnitude seen but forgotten, the floods normally coincide with drought in the Western Cape.

During the years of drought in the Western Cape from 2000 to 2004, Capetonians had restrictions and increases in water tariffs imposed the like of which we hadn’t seen before.  The city even appointed some officers to police water use, which officers disappeared into the woodwork (redeployed), and after higher than average rainfall fell in 2005 all restrictions were lifted with the exception of daily irrigation times(no watering between the times of ten till four 0’clock).  Laughable though it is, this is the only water restriction left, and no police to check on this.  It would be silly too to deploy a police force to check up whether or not you were watering your garden a 10.30 in the morning!

New drought cycle.

We are as I write going into a drought cycle in the Western Cape.  This is going to be the mother of droughts ever seen if the stacked reports from climatologists are correct.  We have been warned of this drought, and our Department of Water and Environmental Affairs should know of this too.  It is strange that the people who work for this governmental department have not applied restrictions in a bid to save water while we still have water in our storage dams. Within eight months there will be panic in local and higher ranking government when we have little or no water.  We will have poor rainfall in the winter of 2011, and 2012 and more than likely 2013. This will mean that the supply dams to Cape Town that are falling at record rates and are already getting low for this time of the year may dry up completely.   There are another three months of summer to go and if the dams continue to fall at this rate (2.8% per week), then expect the dam levels to be at around 45% of capacity by mid April.  It would take a year of higher than average rainfall to put the dams back to where they were at the start of this summer season.  But alas higher than average rainfall is not forecast.  Rainfall of below average is forecast, and perhaps the dams will rise but perchance to less than 80% of capacity.  This is the magic figure at which 30% restrictions get announced, and this decision would be taken in October.

The meaning of 30% restrictions by DWEA

30% restrictions merely mean that DWEA (Department of Water and Environmental Affairs) demand from the Municipality that they show a reduction in demand of 30% less than the volume of water that Cape Town is allocated by DWEA. It is up to Cape Town Municipality as to what restrictions they put in place to lower demand by the prescribed percentage.

Low Fruit

The low fruit has a couple of meanings here.  The first is the low fruit of supply generally, that of dam building and simply robbing rivers of their water. Hereafter desalination of water is the higher fruit as this comes at a price far higher than raw river water.  The second low fruit pertains to the dams, viz water quality in the dams differs from dam to dam, and some are much further away than others.  Also some are deep and others have a huge surface area delivering their yield to evaporation. Actually the aspect of evaporation is very serious.

The low fruit of dam water use has already been picked.  The low fruit of the water in the lower Steenbras dam which though in today’s terms is small, is close to Cape Town and is good quality raw water.  This dam is now below 50% of capacity, and there is precious little inflow to augment the yield.  Although the upper Steenbras is almost full (97%) the majority of this water is stored for electricity power generation. This power generation works under normal circumstances to level the graph of the daily amount of electricity needed for the City of Cape Town which has spikes in the morning and evening, and troughs in the middle of the day and during the night.  During these spikes, water is allowed to flow down to the Gordon’s Bay side through the mountain turning huge hydro electric generators, and in the period of low consumption the water is pumped back up to Steenbras.  However there is a large pipe from the lower dam to the sea, so if we had plenty of water in the upper dam, and needed some extra electricity, this could be used as a hydro electric generation plant until all the water in the dam was used up.  If  we have energy shortages, you bet much of the precious stored water in the upper dam will be used for energy consumption, or at least held in the upper dam for a ‘just in case’, which of course makes this water unavailable for domestic consumption but rather kept for energy generation.

Once the water in the lower Steenbras dams is consumed and it is going fast, then Cape Town Municipality must start to rely more heavily on the poorer quality water from Theewaterskloof and other outlying dams. This water is more expensive to process, and the lower the dam level gets, the worse the quality.

Politicians dam building and jobs.

Election fever has also gripped South Africa, and any immediate talk of water restrictions in the coveted Western Cape must be dispelled.  It seems so strange that the issue of drought which inevitable leads to water restrictions should be seen as bad political management.  The city politicians could not be more wrong.  There is a sense of camaraderie in times of shortages, and we all help each other, and in fact jobs are created during these times.  What is unpopular though is the loss of revenue to the Council when restrictions are imposed.  Revenue from the sale of water goes to the fiscal budget and profits are used wherever the bureaucrats and councillors like.  The less the volume of water that is sold by the municipality, the higher goes the tariffs, and in actual fact an escalation in tariffs is an excellent way of stemming demand for water.  In reality though the city staff who run water supply are well aware that when both tariffs and water restrictions are applied together, the average use per person per day drops which is absolutely logical.  What they don’t like is that the per capita usage once restrictions are lifted never returns to the same point as before the restrictions were imposed and prices escalated.  The following fact is not just surmise:  this is the reason why demand does not increase after restrictions are lifted shows that devices to save water are very effective. Once Water Rhapsody clients use our unique systems, there is no looking back.   The efficiency of the Water Rhapsody Systems goes on and on.  This very important fact was given to me by Dave Ramsay who was the chief water engineer for Cape Town a few years ago.  If only the authorities would realize what they could possible do for our environment by actually promoting water saving with all the tools at their disposal including the devices that Water Rhapsody supply and install.

Job creation through demand management

Far, far more permanent jobs are created during times of drought than the temporary jobs created during dam building activities.   It was so interesting to hear the engineers responsible for the building of the last dam possible in Cape Town, that of the Berg River Scheme, using job creation as a motive to build the dam.  They built temporary houses for their staff and housed them there.  After the dam building process was complete, all the staff were retrenched, and the houses were all sold.  So is it up to those who wish to conserve water to provide jobs?  The answer is an emphatic YES.

Politicians excuse

Of course the fact that there are floods in some parts of the country helps the politicians down play any need for water saving in the Western Cape.  We see daily jockeying for positions for Mayor, party elections, and promises regarding jobs etc.  There is simply no time to address items of so little importance as water, and nobody wants to take an unpopular decision like instituting water restrictions.

Cape Town out of water by 2012

I have stated regularly that the year 2012 will be the year that Cape Town runs out of water.  The debate now will be interesting as to who gets priority over supply of water.  Who will get water in times of outages?  Will farmers get their share?  When Theewaterskloof was built and filled, 90% of water from the dam was assigned for agricultural use.  The farmers though could not use all the water allocated to them and the then DWAF (Department of Water Affairs and Forestry) as it was known then decided that because the farmers did not take up their allocation, that this water would be allocated to Cape Town Municipality.  This gave Cape Town water security in the middle eighties, but since Cape Town has grown so rapidly, this will be insufficient in years of lower than average rainfall, which years we are now in.

Future augmentation – desalination

We have plentiful sea water for desalination purposes do I hear you say?  In order to desalinate enough water to provide one days supply, we will need six million kilowatt hours of electricity. We simply do not have enough energy nor will we be able to find this capacity in the near future. If say at worst we should run out of water completely like Beaufort West.  The average daily demand for water is 1.5 million cubic metres.  The amount of extra energy we would need to desalinate this volume of water would be a minimum of 6 million kilowatt hours every day, for the desalination process.  This water would need to be blended with some other water, most likely treated sewerage water for palatability, and pressurized to municipal pressure.  This would be expensive and with energy we simply won’t be able to find.  Until now all the supply water for Cape Town has been virgin raw water extracted from rivers.  The end to this luxury is nigh.

Water outages

Water outages are a blunt but absolute as an efficient demand management measure (to get people to use less water).  Will we have to endure water outages or wont we?

If everyone installed water saving devices as per the Water Rhapsody Systems of Conservation, we would have no need for measures as tough as outages, but this is not the case. The steps of what can be done culminate in the following:  Install the Water Rhapsody Grand Opus to provide rainwater to the whole household.  This unique system receives rainwater from roofs but is also augmented with municipal water to give all households an emergency supply seamlessly. Water Rhapsody fix the emergency supply from the municipal to your water tank/s for an emergency supply when, (not if) the Municipality turn off the water supply.  If you lived in Beaufort West and had installed the Water Rhapsody System, you would have a contiguous supply, and you would be unaffected by outages.  Secondly should you reduce your demand for water (without a change of lifestyle) you could reduce your water demand (usage) by half.  The reduction in demand is essential to get your precious saved rainwater to go so much further, and is done in five ways viz: by re-using grey water for irrigation purposes, or for toilet flushing, by re-using swimming pool backwash water and lastly by the use minimizing toilet flushing.

As restrictions bite, the municipality will quickly wake up to the erosion of their revenue, and will raise water rates.  These rates will represent the price of the next augmentation scheme, and the capital to provide enough energy for running the water augmentation, that is of course desalination.

All of these systems come at a cost, and the question is frequently asked, can we afford to install such systems?  Our answer is a rhetorical question: can we afford not to do these things?  Well the answer will be a resounding YES as soon as restrictions bite, and bite them surely will!

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