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Melbourne's gigantic Thomson Dam is nearly full - a rare event. DamCam: https://www.melbournewater.com.au/water-data-and-education/water-storage-reservoirs/Tho

Melbourne's gigantic Thomson Dam is nearly full - a rare event. DamCam: https://www.melbournewater.com.au/water-data-and-education/water-storage-reservoirs/Thomson/thomson-dam-cam#/dc/latest https://www.melbournewater.com.au/water-data-and-education/w... 200KM from Melbourne, the Thomson is the main water storage and holds 1,068,000 megalitres. For comparison, Sydney harbour is 562,000 megalitres. The Thomson is at 96% full, and in fact most of Melbourne's dams are full or nearly full according to: https://www.melbournewater.com.au/water-data-and-education/water-storage-levels#/ https://www.melbournewater.com.au/water-data-and-education/w...

bombcar 4y ago
Many dams (Oriville for example) are important parts of flood mitigation - isn’t having the dams nearly full bad for that? Or is the rainy season over?
- 01100011 4y ago
  If it were, i think they'd drain off enough water between storms to preserve some reserve capacity for flood control.
  - quickthrower2 4y ago
    “Between storms” - no such thing for the last Australian summer
- ozzydave 4y ago
  Some dams have additional capacity for flood mitigation, like Wivenhoe Dam in Queensland. Unfortunately that’s not fool proof either: https://en.m.wikipedia.org/wiki/2010%E2%80%932011_Queensland_floods https://en.m.wikipedia.org/wiki/2010%E2%80%932011_Queensland...
- wumpus 4y ago
  If you're asking about California, we're about to start the rainy season.
- andrewstuart 4y ago
  Melbourne doesn't have a rainy season. But when the USA droughts we flood due to La Nina.
- suprjami 4y ago
  I don't know about this dam, but Wivenhoe in Brisbane has various grades of flood capacity. 100% is full of drinking water. This isn't actually "full" and the dam can hold this amount of water twice again - 300% capacity. Up to 200% the dam operator can choose to close or open the dam. Above 200% the dam auto-opens and can retain water to 300%. Above 300% means the dam holds no more and all additional water runs downstream. iirc above 280% the dam wall could be compromised and risk collapse, leading to 0% capacity in a big hurry and the worst natural disaster Queensland would have ever seen. The dam manual for the dams near you is most likely on the govt water website (like Wivenhoe). Settle in for a long PDF which only an engineer could love.
  - bombcar 4y ago
    That's what I was thinking - "100% capacity" can either mean "the design load (still usually 3-5 feet below the overflow spillway)" or it can mean "full for our purposes (power/drinking water, etc)". The first one is the fun one.

bombcar 4y ago

Many dams (Oriville for example) are important parts of flood mitigation - isn’t having the dams nearly full bad for that? Or is the rainy season over?

01100011 4y ago
If it were, i think they'd drain off enough water between storms to preserve some reserve capacity for flood control.
- quickthrower2 4y ago
  “Between storms” - no such thing for the last Australian summer
ozzydave 4y ago
Some dams have additional capacity for flood mitigation, like Wivenhoe Dam in Queensland. Unfortunately that’s not fool proof either: https://en.m.wikipedia.org/wiki/2010%E2%80%932011_Queensland_floods https://en.m.wikipedia.org/wiki/2010%E2%80%932011_Queensland...
wumpus 4y ago
If you're asking about California, we're about to start the rainy season.
andrewstuart 4y ago
Melbourne doesn't have a rainy season. But when the USA droughts we flood due to La Nina.
suprjami 4y ago
I don't know about this dam, but Wivenhoe in Brisbane has various grades of flood capacity. 100% is full of drinking water. This isn't actually "full" and the dam can hold this amount of water twice again - 300% capacity. Up to 200% the dam operator can choose to close or open the dam. Above 200% the dam auto-opens and can retain water to 300%. Above 300% means the dam holds no more and all additional water runs downstream. iirc above 280% the dam wall could be compromised and risk collapse, leading to 0% capacity in a big hurry and the worst natural disaster Queensland would have ever seen. The dam manual for the dams near you is most likely on the govt water website (like Wivenhoe). Settle in for a long PDF which only an engineer could love.
- bombcar 4y ago
  That's what I was thinking - "100% capacity" can either mean "the design load (still usually 3-5 feet below the overflow spillway)" or it can mean "full for our purposes (power/drinking water, etc)". The first one is the fun one.