Leak *into* drain?

[Amedeux]

Hi,
I own a terraced house (ca 1920) in North West London. I recently ran an inspection (the pipe was clogged) of the drain running under the house from the street to the back.
It turns out that there is water ingress. Water is actually leaking into the drain pipe from the surrounding ground!
You can see it in this video:

I was recommended to patch up the holes, but I have some questions:
-where's this water coming from? The Drain runs about 1 meter under the floor. Is there a possibility that there are other pipes running next to it?
-if I patch up the holes, where will such water go? The drainage runs under the living room. Will the water come up to the floor?
-if water can go in, water can go out too. What could happen if the pipe is left untreated?

The last time I had to unclog the drain was about 6 years ago.
Thanks for any advice.

 

[blup]

Maybe a lead pipe leak and the water has built up. Or an old land drain near by.

 

[Murdochcat]

Water logged ground?

 

[Amedeux]

I have spoken to the people who have done the CCTV survey. Before the survey they pressure-washed the pipe. As a result, water was pushed outside the pipe through the holes. They explained that what we are seeing in the video is the pressure pumped water coming back from outside the pipe, through the holes. The CCTV survey was performed immediately after washing. You learn something new every day.