Well, depending on how long they were in the water and whether they were on at the time, they can probably be fixed. It also depends on what kind of liquid you drop the device into.

A lot of electronic devices switch of automatically as soon as they come into contact with a liquid and this is important, because it is not the liquid itself that causes the damage to the device. It is the electric current running through it when the water hits it.

Even if you put a device that is not on in a puddle of clean water and let it stay in it overnight, it is not likely to be irreparably damaged as long as the power was off. You can most likely pull the item out of the water, allow it to dry completely, and it should power back on fine.

I would not advise trying this as an experiment, though, because not every electronic device is made of the same material. As long as you do not attempt to power on the device while it is still wet, it should be alright. Allow the device to dry in a dry, cool area, but not so cool that it will let the device pick up any condensation.

Anything that has been submerged in dirty water, such as flood water, will probably require a bit more attention than that.

Flood waters have been known to contain just about any kind of pollution that you can imagine. Silt, mud, sewage, and other chemicals could be getting inside your electronic device and it will take a lot more than simply drying the device out to get it to work properly again.

Even computer hard drives have been known to be restored with the proper cleaning procedures after having been flooded. The particle debris that has made its way inside the hard drive has to be cleaned out first and quite thoroughly before the drive will work again.

Simply plugging the hard drive back into the computer after it is dry will NOT work and will damage the drive irreparably.

Unless you know a lot about electronics, your best bet is to take whatever water damaged device you have on your hands to a specialist.

Depending on what the value of the device is or if it is a hard drive, the importance of the information stored on it, you might want to fork over the cash necessary to have it repaired.