Tying up a dog for a short amount of time?

My fiance and I have a beagle/collie mix and she has some major digging problems. He decided until we’ve gotten her formally trained; he wants to keep her tied up to the hose/faucet with her leash. He leaves water/food/shelter and her toys out for her to play with. But, I feel this is completely unacceptable and will only tolerate a certain amount of time she’s “tied up”. He doesn’t really care if it affects her personality (i.e. aggression) and believes that being tied up won’t change her.

He does somewhat play with her and he brings her into the house when he can, but half the time she’s tied up. So, when he’s at work…she’s tied up. He’ll let her into the house when he gets home, but eventually ties her back outside until he goes to sleep (which is about 5–6 hours).

Roxie is an incredibly sweet pup. And, I’d like to believe that aggression won’t become a side.

Until I can fence off a safe area for her to roam around in… is tying her up while he’s gone at work bad for Roxie?