Now this is an open sewers pipe, Once you drop down, turn around and proceed down the pipe, after you make a left you will enter a large dead end room with a power box on the far Left and a blocked off tunnel with a infected Lady inside saying some semi-sane sh*t about "the pretty light" talking about the gas flame above her. If you approach the blocked off tunnel entrance with the Infected Lady behind it you will notice something literally flying past in the distant tunnel.
I don't know what it is exactly but it looked like another Suit, and was briefly followed afterwards by two flying Ticks. If someone could make a Brief video about this it would be much appreciated.
Also if you flick the Power box lever all it does is turn off the lights in the room, surely there must be more to it than that? Because in a similar sewer tunnel there is a same power box that you have to turn off to de-electrify the water so you can swim through it and reach the other tunnel on the other side of the water, That makes sence although just turning off the lights doesn't they're must be more to it than this..