That's an entirely different subject isn't it? I don't see how a widen canal would worsen the problem as long as the demand for cross-continental transport persist.

Not at all. The invasive species in question are salt-water animals that traveled through the canal. If there are no controls in place, a wider canal means a larger volume of water flowing toward the Mediterranean, which means more opportunity for invasive species to find their way through. From the Wikipedia article linked:

> A first look at some groups of exotic species shows that more than 70% of the non-indigenous decapods and about 63% of the exotic fishes occurring in the Mediterranean are of Indo-Pacific origin, introduced into the Mediterranean through the Suez Canal. This makes the Canal the first pathway of arrival of alien species into the Mediterranean.

I don't even understand what "controls" means here? Are you talking about turning the Suez Canal into a filtered lock system able to hold Suezmax class ships (160,000 DWT)? Wouldn't the massive energy usage by pumping/filtering that much water (and the usage by the ship's idle engines while they wait) do more environmental damage than the invasive species?

Obviously the correct engineering solution is underwater laser turrets. Mounted on sharks.

We use electrified barriers to prevent Asian carp spread in the Great Lakes region [0]. I'm not sure of the practicality of something similar in a saltwater canal.

[0] https://www.theguardian.com/world/2017/jun/24/asian-carp-gre...

I was thinking of a filtered lock system, and you're right that that's impractical for the Suez.

What about a gillnet?

This ship has sailed long time ago.

https://en.wikipedia.org/wiki/List_of_Lessepsian_migrant_spe...

Wider could have a major effect on terrestrial non flying mammals but zero effect on aquatic animals (except maybe for the biggest whales). Deeper yes, would made a difference for aquatic species.

Maybe would be a good chance to made two roads separated by a chain of islands instead. More expensive but not without extra benefits. By the way reduces the ever present risk of too long ships. With two isolated lanes you can rely always in the other to keep the road opened.

Those chain of islands in the middle could easily hold infrastructures or attract tourism. And would be a great opportunity to became a sanctuary for migrant birds and fishes without blocking so much the migrant mammals.

And if in the future they need to wide even the channel they could just keep the old docks and remove one island in strategic points to connect both lanes and make space.

And could be done in several steps without blocking the activity or income in the old channel.