In article .com,
"Homer2911" writes:
Anyone have experience of claiming against Homeserve insurance in
respect of collapsed sewer/drains?. I'll explain why I'm asking later
- it'll be worth it!

I don't know about Homeserve in particular, but generally, it depends
why the sewer collapsed. If it was just old age, then it's not likely
to be covered as it would come under general maintenance which insurance
doesn't cover (unless it was a special feature of that particular policy).
If there was some specific reason it got damaged such as a JCB bucket
hitting it, then it might be covered.

--
Andrew Gabriel