Tag: rainfall

Is this winter (at last)?

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I don’t want to alarm anyone, but we’re well into May, and we’ve only really had one brief spell of rain so far this year. And that wasn’t even a cold front: it was a cut-off low that wasn’t as bad as anyone really expected it to be. But however the rain fell, it was the only rain we’ve had in over 5 months.

I’m not sure if anyone is getting a bit anxious over this situation, given Cape Town’s recent droughty history. Maybe we’ve all been concentrating too much on the twin disasters of loadshedding and the upcoming election to notice how dry it’s been, but with the dam levels at just 62%, we really could do with a bit of precipitation now, please.

Fortunately, today looks like it might actually deliver. A proper cold front, with a gusty Northwester and anything up to 12mm of rain heading in sometime this afternoon before things thankfully resolve ahead of the footy match I’m playing on Wednesday evening. And then it looks like Friday might chuck a bit more at us, if we’re lucky.

Look, I know that we all wish that summer could go on forever. The sunshine is great for generating electricity, making the decision to braai a lot easier, and encouraging us to get out and about. Not least to the pub. But that’s clearly not practical in even the medium term. You have to take the rough with the smooth when breaking your eggs to make an omelette.

So get your firewood ready, wrap up warmly, and let’s face the 3 months of cold, wet weather so that we can actually enjoy the brighter, warmer stuff when it comes around again. And we can rejoice in not having to use standpipes to get our drinking water.

8.7% up!

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The numbers are in, and Cape Towns dams are officially 79.2% full. That’s a whole 8.7% fuller than this time last week. And that’s a lot of water. I know you guys like numbers, so I’ll pop the increase right here:

78,145,227,000 litres

That’s almost 80 BILLION litres more water than we had last week. Enough to last us almost 100 days at our current usage (which will obviously spike as soon as it stops raining).
Delicious. Just look at the near exponential increase over the last couple of weeks:

This extra water came almost exclusively from the sky, and a quick look at the rainfall figures shows exactly why we are quite literally ahead of the curve.

It’s the 12th of June, and every single rainfall station is ahead of where it should be for this time. Wynberg has already had an incredible 132% of the average rainfall for the whole month. As I mentioned on Saturday, we recorded almost 10% of our annual rainfall in just 36 hours, and the figures from the City bear that out. (Incidentally, the Wynberg figures are almost exactly (like, to the mm) what my rudimentary apparatus recorded in the back garden, which is a good indication that my apparatus is actually pretty decent.) (I’ve been saying that about my apparatus for years, though.)

Plenty more rain is due as well, with another three cold fronts forecast in the next nine days. My surprisingly accurate weather app is saying another 85mm over that period (compared with the exceptional 140mm we had last week). And while we’ll never forget just how scary the Cape Town drought was back in 2018, I do feel that the local population are getting a little fed up of the cold and damp.

The dams are sitting at their highest June levels since 2014. We do still need more though, with Theewaterskloof – which accounts for more than half the City’s water supply – still only sitting at 77%.

But this is a good news story, and we should be happy.

Summer rains

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Good news for the farmers amongst us. Some (or more) good rain expected over the next two weeks.

I don’t want to ruin anyone’s summer, but we always knew that a bit of dampness was always going to be more likely this time around:

And I have no problem with some free water for the garden and the dams. We got a whole 1mm on Saturday, and 5mm the Tuesday before that. I’ve been doing some rudimentary calculations, and I make that 6mm over the last few days. Not bad, but we could always do with a bit more: Cape Town’s dam levels are down to 62% – nothing to panic about, but we’d obviously much rather that they were a bit higher.

That said, I’m still not quite prepared to give up on summer just yet, so if we can have some lovely hot days in between the forecasted showers, that will also be good.

Moon on a stick stuff, I know. But if you don’t ask, you don’t get.

Wet summer ahead

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I mean, it’s not going to rain all the time, but climatologists are predicting that it will be wetter than an average summer. And that’s no bad thing, given that Cape Town generally gets less than 100mm of rain between November 1st and March 31st each year. So a bit wetter than that shouldn’t be too much of a problem.

Wandile Sihlobo, Senior Lecturer Extraordinary at the Department of Agricultural Economics at Stellenbosch University describes the forecast as “comforting”:

And with our local dams also at a “comforting” 85.6% full, it’s all looking rather rosy.

Water-wise, at least.

Also, if the “comforting” rains could just hold off for the next week or so, I’d be really delighted. Please can someone organise that for us?

Thanks in advance.

Day 165 – Hasn’t it been wet?

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Well, no. Not really.

Even though our dams are at a very healthy 95.6% of capacity…

… a far cry from the panic of literally running out of water not so very long ago, this has not been down to this being a particularly wet winter. In fact, this winter has been decidedly average.

graph from here

That’s the 8 months of 2020 so far in orange. Thankfully, not like 2011 (that’s the low line), but also definitely not like 2001 (that’s the very, very high line) either.

So yes, a few things like borehole augmentation, clearing of inflows and a reduction in alien vegetation around the dams will have helped, but it’s the fact that Capetonians are now using only just over half as much water each day as they used to which is making the biggest difference. We’re using just over 630 million litres per day, as opposed to the almost 1 billion litres per day prior to the nastiness of the drought in 2016-2018.

That’s a superb effort.

But…

One of the City’s methods of reducing water usage was to increase tariffs. This probably did have some effect, but now that the dams are nearly full for the first time in 6 years, isn’t it time to reduce those tariffs? The problem is that the City is selling much less water than it used to, while the efforts aimed at avoiding Day Zero two years ago were costly, and the plans to safeguard the city’s supply in a uncertain future doesn’t come for free.
Also, reduce the price of water and it stands to reason that consumption will go up again, which won’t help anyone, but might make up the shortfall in revenue.

Mayoral Committee Member for Water and Waste, Alderman Xanthea Limberg says:

Regarding tariffs: as previously stated, a reduction in tariffs will be dependent on an increase in consumption. Currently, the City is selling approximately 30% less water than before the drought, but is facing additional costs that come with increasing our resilience. It is important that the City cover its costs to ensure that the maintenance and augmentation programmes can be carried out. Should the amount of water we are selling significantly increase this will be factored into the tariffs, but given the uncertain impact of climate change it may not be wise to actively encourage such an approach at this stage.

So. Use less water so we don’t run out, but use more water so that it costs less, so that the City makes more money to make sure that they can replace the extra water you used because it was cheaper to use more water than when you were using less water.

 

Got it.