I read a book about the Panama Canal; and it is certainly one of the greatest engineering feats of all time. But the canal is now a entury old, and too narrow for large ships. The aletrnate route (across Nicaragua, via Lake Nicaragua), could be built without the need for canal locks (it would be at sea level).
Would it make sense to build a new canal? And, would the sea leve canal drive the old Panama Canal out of business?
The wikipedia article seems to indicate so. The Russians might take the project on themselves.
There is a 20 centimeter height difference between the Atlantic and Pacific oceans. There is also an environmental concern of species crossing between the oceans.
BTW, there is an expansion project already in progress, and it uses locks.
Lake Nicaragua is 90 feet above sea level. How would that work without locks?
I think the assumption is that you’d let seawater fill up the extra 90 feet.
You mean the project involves raising the levels of the oceans by 90 feet?
But if Lake Nicarague is 90 feet above sea level, you’d have Lake Nicaragua drain by 90 feet, not have the sea fill Lake Nicaragua
And Lake Nicarague is only 85 feet deep
Other people might not be concerned about directly connecting the Atlantic and Pacific when there’s a height differential between them, but I’d be a bit concerned.
Oops; read your post wrong. The bottom line is that water levels will equalize in some way. If the lake is higher, it’ll drain partly and could be dredged if necessary.
Oh, so that’s why we’re raising sea levels with global warming.
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A far more serious problem is the fact that tides on the Pacific in Panama are some of the largest in the world, up to 18 feet, while tides on the Caribbean are only a couple of feet and out of sync. A sea level canal would still need tidal locks.
A significant concern. Freshwater Lake Gatun, which forms the middle part of the canal, presently prevents most marine species from making the crossing.
The most important component is a new third set of lock chambers, more than large enough to take any existing ship.
Anyone who has sailed near Gibraltar knows of the strong currents there. A canal with no locks would have currents so strong that it would be pretty much impossible to navigate.
This is incorrect. All plans for a Nicaragua Canal traverse Lake Nicaragua, whose surface is 100 ft above sea level. The Nicaragua Canal would necessarily be a lock canal. It would be absurd to drain Lake Nicaragua, especially since using the lake for part of the route instead of excavating a canal is one of the main advantages of the route.
Personally, I think that a Nicaragua Canal requires such a huge capital investment that it is highly unlikely that it will be undertaken anytime soon. While the route is somewhat shorter for vessels moving between the east and west coasts of the US, it provides less advantage for those moving between the Far East and Europe. Given that the Panama Canal expansion will be complete, and allow for passage of any existing vessel, long before a Nicaragua Canal could be constructed, I don’t see any great impetus to build the latter.
Nonsense. Post up the tide times and let the ships surf through that sucker! 
An 18 foot tide sounds bad. But relatively slow rivers have a gradient of a foot or so per mile IIRC. So, it wouldnt take too many miles to make that 18 feet not be a serious problem flow wise.
The bigger problem without locks would be that the water level in the canal near the Pacific end would fluctuate 18 feet, which means you would need to dig the canal much deeper than you would if you just put in locks.
Didn’t we do this thread not long ago in Comments on Cecil’s Columns/Staff Reports?
Pffft! Who reads those forums?
So what would happen if someone dug a canal, say 500’ wide and 100’ deep, with the top of it at the lower sea’s sea level? Would global currents (the conveyer belt) change? Assuming it was kept relatively silt-free, how long before the two oceans eqalized? Months? Years? Decades? Centuries? What about net temperature?
I think you are misunderestimating the problem. The tidal range at the mouth of the Chesapeake Bay is not so big and it creates significant tides and currents on the Bay, like water sloshing along a shallow tray. What an 18 foot tide would do would be just huge. I cannot see how you could possibly just have a canal open to the ecean at both ends. No way.
Especially as short as the Pacific-to-Lake-Nicaragua portion of the canal would be, an 18-foot Pacific tide would probably destroy the ecosystem of the lake. That’s a LOT of salt water (plus whatever marine life came along for the ride) flowing into a fresh-water system.