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A drought has forced authorities to further slash traffic in Panama Canal

westerninvestor.com

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Re: A drought has forced authorities to further slash traffic in Panama Canal

#11

Post by TheSoftwareGuy »

nuc1e0n wrote: post #9

Can't the canal authorities reduce the water used somehow? If you paired up ships so that one going up the lock system is matched with one going down you could just pump the water back and forth from one lock to the other and back. Then way less water would be lost from the system. The Falkirk wheel in Scotland can move boats with minimal electricity usage. Could a bigger one be built?

Most locks don’t actually pump water around. The water level on one side is higher than the other, and thus there is potential energy there. That is how the locks operate

Re: A drought has forced authorities to further slash traffic in Panama Canal

#12

Post by dogsgobork »

donor20 wrote: post #5

One note - they don’t pump water out and back into the locks from a neighboring storage. They flush the water. Each ship needs like 40 million gallons? Maybe title should be insane wastes of water forces authorities…. :)

The new locks do have water saving basins, which reduce the water waste by about 60%.

Re: A drought has forced authorities to further slash traffic in Panama Canal

#13

Post by scythe »

jgord wrote: post #2

I was amazed to hear they relied on large amount of fresh water supply to refill the lochs for each ships passage.

Panama is very rainy on average. The average rainfall in Colón is 3.4 meters (136 inches) per year. Ciudad de Panamá is a little drier with 1.9 meters (75 inches). For comparison, New Orleans, the continental US's wettest city, gets 1.6 meters (64 inches).

But it can vary, and unfortunately, January is the beginning of the dry season, which ends in May.

Re: A drought has forced authorities to further slash traffic in Panama Canal

#14

Post by donor20 »

pacificmint wrote: post #7
donor20 wrote: post #5

One note - they don’t pump water out and back into the locks from a neighboring storage. They flush the water. Each ship needs like 40 million gallons? Maybe title should be insane wastes of water forces authorities…. :)

Isn’t that how all locks work? Or at least most? I’ve always assumed the energy cost to pump the water would make it cost prohibitive, but I wonder how it compares to rerouting ships or moving containers over land.

You can cross fill and use separate storage - their new locks already use this - but my understanding (possibly wrong) was old locks may not have been using all possible options - it’s a cost / benefit trade off

Re: A drought has forced authorities to further slash traffic in Panama Canal

#15

Post by stkdump »

donor20 wrote: post #5

One note - they don’t pump water out and back into the locks from a neighboring storage. They flush the water. Each ship needs like 40 million gallons? Maybe title should be insane wastes of water forces authorities…. :)

I had to check if that realistic. 40 million gallons at 85 feet is 11MWh of potential energy. At 70% efficiency it would take 16MWh to pump that. That has to be a small amount of energy compared to what ships take for traveling the detour.

Re: A drought has forced authorities to further slash traffic in Panama Canal

#17

Post by namaria »

mattmaroon wrote: post #16

I guess it never occurred to me it was fresh water. Can they not just use salt water?

The canal is connected to a natural fresh water system. You can't just pump salt water in there without risking a massive ecological disaster.

Re: A drought has forced authorities to further slash traffic in Panama Canal

#18

Post by aidenn0 »

bluejekyll wrote: post #10
pacificmint wrote: post #7

Earlier quoted context omitted.

Isn’t that how all locks work? Or at least most? I’ve always assumed the energy cost to pump the water would make it cost prohibitive, but I wonder how it compares to rerouting ships or moving containers over land.

Ok, I’m no civil engineer, but couldn’t you design a siphon system that would only require opening and closing valves to capture the water without any pumping?

No; at some point you're going to lift the water up. That requires pumping.

Re: A drought has forced authorities to further slash traffic in Panama Canal

#19

Post by huytersd »

donor20 wrote: post #5

One note - they don’t pump water out and back into the locks from a neighboring storage. They flush the water. Each ship needs like 40 million gallons? Maybe title should be insane wastes of water forces authorities…. :)

They really should use solar arrays to pump the water back. If there’s no sun, you can always just flush it like they’re doing now.

Re: A drought has forced authorities to further slash traffic in Panama Canal

#20

Post by dumbo-octopus »

namaria wrote: post #17
mattmaroon wrote: post #16

I guess it never occurred to me it was fresh water. Can they not just use salt water?

The canal is connected to a natural fresh water system. You can't just pump salt water in there without risking a massive ecological disaster.

You could pump water to the highest lock lower than the lake though.

But salt water doesn't mix well with things not intended for salt water.

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