sewerage problems

My name is george and I live in NSW, Australia.
My sewer is blocked between the inspection plate and the main sewerage pipes; there is only one metre between the two.
I have dug to about a metre from the main sewer pipe and opened an inspection hole.
Do I have to dig all the way to the main? Or does anybody know how my sewer connects with the main?
For example, does my sewer pipe go all the way to the main and then drop vertically? Or does it go diagonally or any other way down?
Thanking you in advance,
George.

It's hard to say. In the USA, sewer lines typically slope around 1/4" per foot. Note that larger pipes don't need quite that much slope, and more is okay as well. Normally, where there is a 90-degree angle, there is a cleanout since an auger or snake with a cleaning head on it has trouble sometimes going around that bend. Good design would probably dictate that from the cleanout/inspection it runs fairly straight to the main sewer line.

Tree roots are one common thing that will block up sewer lines. Another is a collapsed or broken line that can happen if any heavy construction equipment was running over the area.

Don't they have to slope up in Australia?