I wouldn't waste your time trying to deter them. I mean really, what are you gonna do? They live underground.
You'll have to trap them. I trapped gophers for years as a kid growing up on a hobby farm. Here's what you do:
1. buy the cheap gopher traps (hardware store)
2. dig out the freshest hole(s)
3. get the trap ready and push it in as far as you can, while still leaving room to stake it
4. get some sleep
5. discard dead gopher
Like anything, the traps may not work everytime. If the gopher abandons the tunnel you've set up, the trap obviously isn't going to work, but you'll get them eventually.
6. have fun, cuz trust me, trapping gophers is A LOT of fun ???