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The man who came out was just assessing it ie, sussing out exactly where it is, how serious etc and now he's gone away and I expect a gang will appear sometime soon to do the repair. I was intrigued to see him using divining rods to sort out exactly where the leak comes from. I knew someone back in my working days who had tried divining and said it worked, so I had some faith in it. This engineer said he uses it all the time and it's amazingly accurate.