Risk to (waste) water pipes from tree/shrub roots

We have two of those in the current garden, they should go with ... but then they have to be placed in the back garden area

I went to get advice at the nursery today.

The [Felsenbirnen] have heart-shaped roots. The roots grow as large as the crown.

I will now plant grasses near the water pipe. [Puschelgras]

Hello,
after our on-site appointment last week, it is now certain that we will find similar conditions.
We want to integrate the front garden into the garden, let's see how we design it.
Best regards

Hello everyone,
thanks for your contributions.
My husband researched, there is now a technology where companies can use a camera to look inside drainage pipes, and if roots have grown in, they are cut off and the spots are sealed with epoxy resin – all from the inside and without digging up the pipes. So to speak, "endoscopically." I don’t know what it costs, but at least it relaxes me a bit regarding the garage. It would definitely be less effort than digging up paths and soil.
Unfortunately, for the spots further west along our house wall, that is not a solution either, because there are also drinking water pipes and hoses with coolants buried there.
But maybe this info helps you.
At least for me, it will be either knotweed or rose at the garage!
The house will just remain bare, with little boxwood balls and perennials in front, so be it.
Best regards

The inlay method was applied in the house we sold last year due to water damage. It is not cheap! It cost nearly €2,000 for 9 meters. We are currently working with our excavation contractor, who also partly acts as a landscape gardener, on the critical spot. The gardener recommends various ornamental grasses. I hope that we will be finished with the parking spaces in four weeks. Then I can provide more details about the plants.

2000 € ! O.O Ouch. Probably still much cheaper than if paving stones have to be removed, soil dug up, pipes taken out and then everything put back.

Oh, unfortunately these grasses are not to my taste... This is always planted here at companies and practices, meters of sedge.
I think I always have my grandma's garden in mind.
I want sprawling shrubs, vines and flowers!
Well, but avoiding damage and being able to maintain it easily comes first. Then I'll just do whatever I want in the back garden!