3 ms·

It would certainly empty out the public water towers or cisterns in a hurry.

krisoft 14y ago
Exactly my thoughts. If any civil engineering out there could answer the question: Could this type of coordinated action lead to some 'cascading failure' in the water system? Or it would just drastically reduce the pressure, and that's it?
- stevoski 14y ago
  Do residents in Zimbabwe mostly use a joint water system? Or do they have individual water tanks?
- snowwindwaves 14y ago
  if everyone simultaneously cooperates to increase the demand on any network beyond its capacity then the the network is not able to supply any additional demand. In the case of the electricity network, either demand is reduced or the whole thing grinds to a halt and nobody gets any power at all when the load exceeds the generation. In the case of the water supply system water would cease to flow at points in the network when pressure reached zero. what is there to fail? an extended demand exceeding supply could empty reservoirs folks who engineer communication networks really have the most control over what to do when demand exceeds capacity as they can prioritize some demand and curtail other demand.
- jordanb 14y ago
  Toilets have their own reservoirs, so the flush wouldn't have any effect on the supply side of the system. And I think that's the point: there's more water stored in distributed toilet reservoirs than the city could dump in through a centralized point. Refilling them all at once may exceed the city's ability to supply pressure though. If pressure is provided by pumps, they'll increase their flow rate to maintain pressure until they reach their maximum rate, at which point the pressure will fall. On the sewer side, I could see the flush creating water hammers that damage various parts of the system. I could see them reasoning that they can do the flush and then go ahead and repair any water hammer damage, and that will be easier overall dealing with thousands of blockages.
- gregcohn 14y ago
  This was exactly my question/concern in posing the link. And, of course, I'd love to understand what the consequences of such a failure would be.
ars 14y ago
It would do no such thing. 3.4 gallons * 1 million = 3,400,000 gallons. A single typical water tower holds approximately 400,000 to 500,000 gallons, and I'm quite sure a city of that size has more than 7 of them. A small reservoir holds around 500,000,000 gallons.

Exactly my thoughts. If any civil engineering out there could answer the question: Could this type of coordinated action lead to some 'cascading failure' in the water system? Or it would just drastically reduce the pressure, and that's it?

stevoski 14y ago
Do residents in Zimbabwe mostly use a joint water system? Or do they have individual water tanks?
snowwindwaves 14y ago
if everyone simultaneously cooperates to increase the demand on any network beyond its capacity then the the network is not able to supply any additional demand. In the case of the electricity network, either demand is reduced or the whole thing grinds to a halt and nobody gets any power at all when the load exceeds the generation. In the case of the water supply system water would cease to flow at points in the network when pressure reached zero. what is there to fail? an extended demand exceeding supply could empty reservoirs folks who engineer communication networks really have the most control over what to do when demand exceeds capacity as they can prioritize some demand and curtail other demand.
jordanb 14y ago
Toilets have their own reservoirs, so the flush wouldn't have any effect on the supply side of the system. And I think that's the point: there's more water stored in distributed toilet reservoirs than the city could dump in through a centralized point. Refilling them all at once may exceed the city's ability to supply pressure though. If pressure is provided by pumps, they'll increase their flow rate to maintain pressure until they reach their maximum rate, at which point the pressure will fall. On the sewer side, I could see the flush creating water hammers that damage various parts of the system. I could see them reasoning that they can do the flush and then go ahead and repair any water hammer damage, and that will be easier overall dealing with thousands of blockages.
gregcohn 14y ago
This was exactly my question/concern in posing the link. And, of course, I'd love to understand what the consequences of such a failure would be.

ars 14y ago

It would do no such thing. 3.4 gallons * 1 million = 3,400,000 gallons. A single typical water tower holds approximately 400,000 to 500,000 gallons, and I'm quite sure a city of that size has more than 7 of them. A small reservoir holds around 500,000,000 gallons.