Main pipe in sink is dripping

[Zachwulf]

I've had this problem for awhile now. There's been some really bad scum buildup under my bathroom sink, so I took apart the u-bend and the PVC that connects to the main hose that goes into the wall and cleaned those out, but I noticed that the main black hose is dripping. This leads me to believe there's some kind of leak in the main water distribution system in my house, because essentially water is leaking from the wall, through the main pipe.

I turned off the water to the sink, but the dripping persists. I've attached some pictures to help illustrate. The black hose is where it's dripping. The rest I've disassembled and cleaned.

Thanks for any help in advance.

Picasa Web Albums - ZachWulf - Plumbing

Picasa Web Albums - ZachWulf - Plumbing

[havasu]

I will try to help you but I can't guarantee anything. I've never seen this type of system before. I see your hot and cold supply lines, and your white "P" trap which drains to your sewer system. What on earth is the black pipe for? It actually looks like a dishwasher discharge line, but from your pictures, I have no idea where it connects. I do see this black pipe has hose clamps on each end, and it is possible the rubber has swollen.

By the way, are you in the United States? I know other countries have plumbing problems and codes allowed in specific regions, that I'm not familar with. If possible, can you provide more information in order to better help you?

[Reedwalker]

A picture of how the black hose was hooked up originally may help.

I agree that it is likely the dishwasher discharge but, I've never seen it done like that.