I recently had to install an outdoor electrical recepticle for a fountain.
This new recepticle was wired in series from an outlet in my backyard,
using 12-2 outdoor wiring. My question is, do I need to use conduit
underground, or can I just bury the wire 12" deep? I've heard conflicting
stories on this. Someone told me that an electrician told them anything
underground had to have conduit around it in case a shovel or something
else were to hit the wires. However, I've also heard that conduit can
cause the wires to overheat and that it defeats the whole purpose of having
outdoor wire in the first place. Which is correct? I haven't been able to
find the electrical codes for WA online, which is why I am asking here.

Also, do I need a GFCI on an outdoor outlet? Someone told me it is a bad
idea to use a GFCI for a fountain or anything with a motor because
fluctuations of the motor can cause the circuit to trip. This made sense,
but if a GFCI is required outside, how else are you going to get power to a
fountain?

Any help would be greatly appreciated. Thank you.

Matt