So I'm working on a story based on a binary system involving two Earth sized, Earth like worlds with very eccentric orbits. In the story, one of the major coastal cities is protected by a massive retractable seawall to protect it from a titanic tidal wave (known as the Leviathan) which occurs as the two worlds swing past each other at periapsis. But after a terror attack disables the seawall from deploying, the Leviathan literally wipes away any trace that the city was there; carrying away what ever debris it made and leaving only the concrete foundations and empty streets in it's wake.

If you need details about the orbit, the two planets are roughly the diameter of the Moon's orbit apart at apoapsis, and only about 20,000 km apart at periapsis. One planet, named Horizon is 93% the Earth's diameter, and the other is 89%; with both having roughly the same density as the Earth. So, could the Leviathan exist; and if it did, how big would such a tidal wave be?

So I'm working on a story based on a binary system involving two Earth sized, Earth like worlds with very eccentric orbits. In the story, one of the major coastal cities is protected by a massive retractable seawall to protect it from a titanic tidal wave (known as the Leviathan) which occurs as the two worlds swing past each other at periapsis. But after a terror attack disables the seawall from deploying, the Leviathan literally wipes away any trace that the city was there; carrying away what ever debris it made and leaving only the concrete foundations and empty streets in its wake.

If you need details about the orbit, the two planets are roughly the diameter of the Moon's orbit apart at apoapsis, and only about 20,000 km apart at periapsis. One planet, named Horizon is 93% the Earth's diameter, and the other is 89%; with both having roughly the same density as the Earth. So, could the Leviathan exist; and if it did, how big would such a tidal wave be?