> It requires 200m litres of water to allow the passage of a single vessel along the canal, water that is largely generated from Lake Gatun in the centre of the waterway, which is drying up fast.
Canals take water to use. Not just the water that fills them, but every time a boat travels along the canal, a certain quantity of water is lost. That's because water has to be moved up and down with boats that go up and down over hilly terrain, but rather than using pumps to do this, gravity is used. But gravity only takes water downwards - if you want to have water high up again, you need new water.
This quantity can be reduced with careful design of the canals and there can be tradeoffs between water use and canal throughput - for example, if you only transport ships that require less water depth, then you can waste less water per ship.
This notification is saying that due to water shortages, they are having to do all these tradeoffs - with the end result being that some ships will be turned away, and the ones that do pass will have to be not fully loaded, and will take more days to get from one end of the canal to another.
> It requires 200m litres of water to allow the passage of a single vessel along the canal, water that is largely generated from Lake Gatun in the centre of the waterway, which is drying up fast.
1) Desalinate sea water and pump it up to Lake Gatun.
2) Build catch basins next to each lock that can take half the water from each lock when the level is being lowered and can then give it back to the lock when the level is being raised.
3) Lower blocks of shipping containers that are heavier than the water they displace into a lock to occupy any space a ship does not occupy. Less water will then be needed to operate the lock.
Just realized an easier way to implement 3 is to just have a filler ship that is used to fill any unused space left in a lock but which does not leave the lock area and just waits until it is needed again to fill the lock in the opposite direction.
For context. The geography of the canal: https://upload.wikimedia.org/wikipedia/commons/9/91/Panama_C...
And a horizontal cross section of the canal: https://www.researchgate.net/publication/258387615/figure/fi...
Gatun Lake sits upstream of the sea, so they can't just open the locks to "fill" the lake.
This stands in contrast with the Suez Canal, which has no locks or elevation. It's nothing more than a long horizontal trench dug through the desert.