Toilets, Sinks, Showers, Tubs and Disposals - cold water supply to kitchen sink

My son called me, his cold water was running very slow, at the kitchen sink. The hot water runs fine. The cold water in the bathroom, runs fine.

I told him to shut the water off, remove the faucet, chek that. He said it wasn't the faucet or seat. I don't know how he decided that, cause he can't shut the water off. The shutoff is in a manhole and the lid is locked. We don't live in the same town, I haven't looked at it. I told him he needed to find a key for the lid, maybe a plumbing store has one?

If it wasn't the faucet or seat causing a problem, maybe he could snake the supply line, if there is an obstruction, may be he can jar it loose? If that doesn't work, I don't know what else to do, except replace the supply line? Any ideas? thanks

First: Ask him how he decided that - cause you're right on.. the obstruction is somewhere from the main piping to the sink to the sink valve itself.... Sounds like he's guessing - and without more specifics - it's gonna be difficult to troubleshoot... BTW - can't snake a supply line....

Thanks for the reply, If he doesn't get a chance to do anything before this weekend, I may try to go over there and try to help him. thanks