I remember one set in Sheffield, and I think it was called Threads. In particular, I remember the final scene where the girl who had been born as the bomb went off ,(who was now about 14) ,gave birth . She was screaming as the baby was deformed/dead, and all I could see is that she had loads of filings in her teeth (she was supposed to have grown up in a world with no health care !)
My guess is Edge of Darkness, but I remember threads too. When you say nuclear do you mean war or enviromental issues. Also just remembered something I think was called "The last train" which was about some survivors of some disaster but I can't remember what happened, any ideas ?