Meanwhile, Matt was busy exploring that hole he had floated into.
Certainly this can't be right....no...after staring at the floating fish heads for a few moments, he realized that probably, this might just be his brain's outcry for oxygen as he was duh, underwater. So Matt struggled to pull himself out of the water and back onto a ledge of the sewer. Then pulling himself to his feet with whatever he could grab to help pull himself up.
"Ugh...toxic water...dripping....and what the hell was this I just grabbed? Hopefully nothing bad..."
The rumbling noise coming from someplace downstream might say otherwise. Indeed.