the best fix is replace the line, followed by removing the
offending tree thats generating the roots.


in our case the line is terracota and almost every joint had roots.


i dump 20 pound sack of rocksalt in the washtub 3 or 4 times a year,
espically early spring. it kills the roots while leaving the tree
safeand is so cheap its nearly free.....


just plain old rock salt, add lots of hot water stir, then leave for
work so salt water remains in line.


no clogs since i started doing this about 7 or 8 years ago.

another option is this, they clean the line really well and dig it up
at both ends. they pull a kinda sock thru it, then pump it fast with
very hot water and let it sit for a day. the plastic expanded to the
interior of the line is smooth and prevents leaks which attract roots.

open both ends and you are back in business with no major digging.

this material is expensive but can be done fast.

frankly the salt water works great for us. although when theres extra
money the line will need replaced