I try not to kill even the black widow spiders I catch almost weekly and baby rattlesnakes I catch ever few months.
I relocate them to a far corner of my property. These gophers, I'd relocate, if I could. I first tried noxious chemicals to try to French them out, but, so far, that hasn't worked.
Now I'm moving one notch up, by soaking them out. I have hilly property, so, on purpose, I chose a hole that was halfway on a hillside. There is about four feet above and below the hole that is soil (concrete being on both sides of that).
So, I'm hoping that the 5,000 gallons of water I just put into two of those holes will flush them out. They're welcome to find another spot to live, as I have plenty of non-grassy land further from the house.
Let's hope they got the hint, because I plan on giving them another 5,000 gallons of water (4 hours, 3/4" hose, 80psi) from the two hoses again tomorrow.