Thames Water say I have to install a gully divider

[ETO]

Should more than suffice, doesn't look like the DPC has been breached. No way the waste gully can now overflow into the rainwater gully now, but to be fair, if the gully was clear, it shouldn't have overflowed in the first place!

Thank you.

I am still not clear if I had a responsibility to install a gully divider, or just keep the gully clear. After all, the neighbour has the same setup, and I suspect many other houses on the street do too.

However, the letter from TW suggested to me that I needed a gully divider regardless, so that is what I have had installed.

Originally I had thought it it must require some work underground to separate the gullys, but it seems that isn't the case.