Asking most dogs to stop digging is like asking them to stop eating. Digging is an instinctive behavior. It is almost impossible to change an instinctive behavior, but you can try to control it.
Dogs will dig in the winter to find shelter from the cold and wind, they will dig in the summer to provide a cool hole to lie in, but the number one reason dogs dig is because they are bored. If your dog is banned to the yard all day or is a permanent “outside dog”, he will dig out of boredom. Dogs have a strong need to be included in the family, and a 10 minute visit each day to feed and water him is not enough. It is strongly recommended that you bring the dog into the house and make him a part of the family.
When your dog is in the yard, make sure that he has enough toys to amuse him. Give him chew toys, balls, sterilized bones stuffed with “goodies”(peanut butter, Cheeze Whiz, etc.) and anything else the dog likes.
Some of the things you can do to try to hinder digging are: bury bricks in the holes (dogs want to dig in dirt, not bricks), put the dogs stool in the holes and bury it, put chicken wire where he likes to dig, bury water balloons in the holes so that when he digs the balloons will brust in his face.
Give the dog his own digging place (perferably in a shady spot) and teach him to only dig there. Bury a couple of his toys in this spot, call him over and encourage him to dig there. If he won’t start digging, then dig yourself and in an excited voice tell him “good dog, dig, dig, dig”. Make it a game. When he digs in his spot praise him. Keep an eye on him, if he starts to dig someplace else, correct him by leading him to his digging spot and encourage him to dig there. Every couple of days, turn the dirt over in his “digging place” ( dogs love to dig in freshly turned dirt).