[onetwo_threefour]

If you can't get at the valve try using a flat bladed screwdriver to pop the cover off the faucet handles (assuming you have a separate hot and cold faucet and they are just rotating handles) Behind the cover should be a screw and you should be able to tighten it down enough to turn off the water if the faucet handles are just spinning on the spindles. Either that or take the screws out, pull the faucet handles off and use a pair of pliers or a wrench to turn the faucets off.

If you have a single handle, there may be a screw behind the handle or a set screw on the side, but usually the set screw requires an allan key to loosen. The poiont is, if you can get the handle(s) off you should be able to manually turn the water off.