Completing Water Troubles in Arc Raiders shouldn't give you too many problems once you've found the Flood Access Tunnel location. Just like Market Correction or A Reveal in Ruins, it's a simple two-parter consisting of tracking down a location and then interacting with an object inside—no item extraction needed, thankfully.
The quest itself gives you a pretty big clue as to where to find the Flood Access Tunnel, mentioning that it's underneath Red Lake Balcony, but this isn't technically correct. The tunnel is a little ways off to the side of the balcony, explaining why this might be tripping you up. So, here's how to complete Water Troubles in Arc Raiders.
