I agree that an electric fence isn't enough on it's own. My friends had one for their dog, plus a 6 foot wooden fence. This dog could JUMP the fence, and he knew that the little zap lasted for only a second and he could still be free!! He would just jump over extra fast to get minimal zaps. I hope that you find a good solution that involves keeping the dogs contained, in some way, because it is way too risky to let them roam no matter where you live.