Rain and storm for Cpt

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Already started with light rain in Gardens/Higgovale area.

@2000 - Jonkershoek at just under 78mm!
 
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Very wet in Kenilworth, 26mm in gauge up to 8pm (mostly from 6pm onwards).

Very wet at SAEON Dwarsberg (Jonkershoek mountain catchment) with more than 60mm up to 8pm.

The Berg River Dam is starting to creep up again (rather low soil moisture this week). The level was at 90% this morning, and might reach 100% this year...
 
Plenty of run off in du Toit's Kloof pass this morning when we passed through there. Lots of wind. No sign of the front moving inland yet. Matroosberg under heavy cloud. Temperature in Beaufort West this afternoon was 16. 21 on the farm in Hanover when we arrived with strong NW winds.
 
Hout Bay got very wet.
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Glorious water from the heavens, I took my prostate for a piss around 03h07 this morning,as I sat on the cold ceramic seat, the window behind me allowing the unseasonal cold air to drift into the house, I shivered and then the heavens opened....

Cold winter rain fell over my corner of the desert twice in the last five hours, reminding me of the winters from more than a decade ago.

Lucky for me, no work today, so there be a good chance I shall stay tucked up in bed watching the swirling clouds drift in from the west...
 
The main front has now passed over Cape Town, and there are significant gaps between the showers (though it will remain wet for most of the day).

Our gauge in Kenilworth recorded another 12mm overnight, bringing the 24 hour total to 38mm (up to 8am).

The SAEON stations reported impressive totals (up to midnight), Dwarsberg (Jonkershoek) had 96mm, Constantiaberg (CT) 47mm, and Engelsmanskloof (Cederberg) 22mm. Further heavy falls are likely, though two gauges are now frozen (snow!)

I was half-hoping for snow on Table Mountain, but can't see anything. The webcams at Sutherland show modest falls (very cold but not a lot of moisture). Most peaks in the SW-Cape above 1200m will receive heavy snow, though it will remain cloudy for most of today.

The level of the Berg River Dam jumped nearly 2% overnight, currently above 92%: http://www.dwa.gov.za/hydrology/Unverified/DetailStageFlow.aspx?Station=G1R004FW&Type=Flow

zizo911 said:
Any one think the the dams might make it to 80% this year before the summer season?
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The average CT dam levels could reach 70% soon, but 80% this year seems a stretch....
 
Gordon_R said:
The main front has now passed over Cape Town, and there are significant gaps between the showers (though it will remain wet for most of the day).

Our gauge in Kenilworth recorded another 12mm overnight, bringing the 24 hour total to 38mm (up to 8am).

The SAEON stations reported impressive totals (up to midnight), Dwarsberg (Jonkershoek) had 96mm, Constantiaberg (CT) 47mm, and Engelsmanskloof (Cederberg) 22mm. Further heavy falls are likely, though two gauges are now frozen (snow!)

I was half-hoping for snow on Table Mountain, but can't see anything. The webcams at Sutherland show modest falls (very cold but not a lot of moisture). Most peaks in the SW-Cape above 1200m will receive heavy snow, though it will remain cloudy for most of today.

The level of the Berg River Dam jumped nearly 2% overnight, currently above 92%: http://www.dwa.gov.za/hydrology/Unverified/DetailStageFlow.aspx?Station=G1R004FW&Type=Flow



The average CT dam levels could reach 70% soon, but 80% this year seems a stretch....
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What happens if the Berg River Dam reaches 100%? Will there be an overflow into another Dam?
 
mercury12 said:
What happens if the Berg River Dam reaches 100%? Will there be an overflow into another Dam?
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Yes, as stated repeatedly in various threads (the dams in the CT catchment are interconnected). The obvious place to pump excess water is Theewaterskloof, which seldom fills up naturally.

Still some lingering showers here, with light hail in places.

It will be very cold over most of the interior of SA today, though the rainfall will be restricted to the SW-Cape and West Coast only.
 
Very light hail and steady rain here in Parklands. Saw pics of glorious snow on the mountains around Robertson. Hopefully some of it finds its way into the dams.

There goes my plan to do a load of laundry today...:rolleyes:
 
Average CT dam levels up 1.9% to 62.0% during the week to Mon 27th (most of that inflow in the last 36 hours).

Weekly report: http://resource.capetown.gov.za/documentcentre/Documents/City research reports and review/damlevels.pdf
Daily report: http://www.capetown.gov.za/Family and home/residential-utility-services/residential-water-and-sanitation-services/this-weeks-dam-levels

There may still be runoff during the next few days, but no significant rain is predicted during the next 7-10 day period.

Near real-time charts for Berg River, Theewaterskloof and Voelvlei Dams:
http://www.dwa.gov.za/hydrology/Unverified/DetailStageFlow.aspx?Station=G1R004FW&Type=Flow
http://www.dwa.gov.za/Hydrology/Unverified/DetailStageFlow.aspx?Station=H6R001FW&Type=Flow
http://www.dwa.gov.za/Hydrology/Unverified/DetailStageFlow.aspx?Station=G1R001FW&Type=Flow

Edit: The SAEON Dwarsberg (Jonkershoek mountain catchment) recorded a phenomenal 62mm up to midnight on Mon 27th. This was a combination of delayed snow-melt from Sun 26th (when the gauge was frozen and only 2mm precipitation was recorded), as well as persistent moderate rain during the afternoon (the cumulative total was 160mm in 72 hours).

Edit: The level of the Berg River Dam jumped another 1.5% (in 24 hours) to 94.3% as a result of this subsequent inflow, and is certain to reach the high 90s by next week. Theewaterskloof continues to received limited inflows, but Voelvlei has shown consistently runoff from the Little Berg River over a longer period of time (Tulbagh/Ceres catchment). The charts show a sharp rise in the rate since the start of the cold front, up 4% (in 48 hours) to 73.3%.

Edit #2: The level of Theewaterskloof has increased by 3% in 3 days, more than can be accounted for by rainfall, while the the level of the Berg River Dam is peaking around 95%. IMO it seems likely that water is being pumped from one to the other (for the first time in 3 years!)
 
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air said:
Decent uplift, now at 63.5%, should exceed 65% by Friday :)

Yep, about 300M litres per day is being pumped, also mentioned in the below TB report.
Tom Brown -> https://showme.co.za/paarl/lifestyle/nature-outdoors/cape-water-and-dams-report-119/
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Thanks for the info (and the link which I always forget to check).

300Ml per day sounds relatively high (more than half of our current daily consumption), but is only equal to about 0.25% of the Berg River dam capacity per day. This amount is quite modest compared to recent the daily increases of around 1.5% per day (inflow over 1500Ml per day for Berg River alone). Hence it makes sense to start transfer/pumping at the 90% level, before the dam overflows!

The full impact of the weekend storm is still being felt, with the average dam levels up 1.5% during Mon 28th, and likely to have increased by a similiar amount this morning: http://www.capetown.gov.za/Family and home/residential-utility-services/residential-water-and-sanitation-services/this-weeks-dam-levels

Edit: Average dam levels for CT reached 65.1% this morning (Thurs 30th). This is a 5% increase in 10 days, from one series of cold-fronts!

Several model runs predict that the the next major cold-front, due on Tues 4th Sep, should produce significant rain and more snow for the SW-Cape.

Sadly, recent cold-fronts have done nothing for the water situation in the Eastern Cape.

Edit: Long range forecasts show good rains over the Garden Route and E-Cape late next week (Thurs 6th onwards).
 
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