I'm 27 Weeks And My Feet Is Swelling Badly While

I'm 27 weeks and my feet is swelling badly while I'm at work sitting and also standing . I always go home and elevate them and also soak them as well . I been drinking a lot of water daily , but I'm thinking maybe it's not enough . I try to stay away from salt as much as possible , everyday my my feet are Huge . What should I do ?