Water treatment huge fps drop

https://clips.twitch.tv/GlamorousShortSkunkLitFam This is a clip of my gameplay that shows 40~50%ish drop in fps when in a certain section of water treatment.

My setup is 4790K and 1080GTX

all low 1080p

limited by rivatuner to 144

A buddy of mine with a 8700K and a 1660Ti gets around 120~ fps there while I get dropped to 80~90.

4790k isnt enough for 144 all low?

Is the map bugged?

all I want is 144 smooth and I think 1080p\all low should allow my setup to go with that (most of the time it does)