Moving kitchen and plumbing from front to back - how?

[mickeymoose]

We're planning an extension on our semi-detached house. The kitchen is currently at the front of the house, but it would be nice to move it to the back, and install a utility room at the back of the garage. However, all the plumbing is currently at the front. How exactly would they move it to the back? There would be no side access to the back of the house, so would the supply pipes and drain have to run under the garage? Is that even possible?

Oddly, we do have a manhole cover behind our house, but this seems to drain rainwater from ours and adjacent properties. I think it runs under the garage but not totally sure.