Low detail planar reflections

I was just playing Uncharted LL and noticed that the game actually used planar reflections, which is a bit rare to see nowadays. It seems like games just use cubemaps and SSR these days, which i thought Uncharted did as well. But i noticed the reflections stayed when i tilted the camera down so you could only see the water.
But not only does Uncharted LL have planar reflections, the reflections are low poly/detail, which is good for performance.

Im wondering how this is done. I thought it might have been that the camera for the planar reflection, had different cascades for LOD. But that'd be weird cause Uncharted is pretty linear and there is really not a big need for LOD in most scenes. But then i thought that it could have been a culling mask type situation. That's the only way i could think it could be recreated in unity easily. You have both levels of detail in the scene, but the main camera can't see the low poly models, and the reflection camera can't see the high poly models.
It could be that they created LOD specifically for the scenes with bodies of water though.

What do you think? How could this be done?

 

You could have two scenes, or you could have your objects already be using LOD groups. When rendering the planar reflection, you should be able to change the

QualitySettings.lodBias

before rendering the reflection camera, and then change it back to whatever the previous value was afterward to force the LODs to render.

 

Oh ok, i wasn't aware that LOD could be forced like that. Thanks for the answer!