[eskathos]

working at a tier one telco. we have very precise maps of our ground fibers. physical location is usually down to +-10cm. length of fiber even takes into account any coiled up parts. if a contractor wants to dig anywhere, then they have the responsibility to query a national database before digging. if they break our cable, then we have active monitoring (reflecting a laser in a spare fiber, off the break, calculating length to break) this interfaces with our map software, so we can tell within half a meter where the cable is broken. in most cases we end up suing the contractor for the cost of repair and any SLA payments.

to my knowledge no public maps exist, that will give you a full picture.