Certified GKH Gardening Expert
Eucalyptus roots tend to be shallow compared to other trees, going down about 6-10 feet normally. They are very water hungry and if they cannot find a way to get enough water in the soil, may invade pipes. You can try giving it extra waterings, to keep it from seeking out water from the pipes or redirect runoff water to the tree for the same effect.
Sap is not typically a big problem with these trees unless there is a pest problem or disease present.