It was Northumbrian Water who told us it wasn't their responsibility not the man who jetted the drain. We need to find out if the plans should be updated in case it happens again.Contractors may well tell you it's your responsibility, they're hoping for repeat business! Plans are not your responsibility, but believe me, the plans are just a guide anyway. A lot of smaller sewers may not be recorded, and I know of some huge omissions on our system, one glaring example is the job I worked on at 16 when I first left school, we laid a 375mm diameter storm sewer in parallel with an existing, to double the capacity of the system, and none of it is mapped!