the best thing you can do Northbeach is;
dig a hole to expose the drain pipe, then enlarge the hole to about three feet by three feet. graft in a 450mm osma or similar plastic pre- formed inspection chamber bottom, with sufficient risers and lid. back fill.
you will now be able to access your drains at your leisure.
if the drain is greater than say 30-36 inches deep, then the pre- formed manhole will not be suitable.
if you can locate the junction even better.
dig a hole to expose the drain pipe, then enlarge the hole to about three feet by three feet. graft in a 450mm osma or similar plastic pre- formed inspection chamber bottom, with sufficient risers and lid. back fill.
you will now be able to access your drains at your leisure.
if the drain is greater than say 30-36 inches deep, then the pre- formed manhole will not be suitable.
if you can locate the junction even better.
