it mite be a bee that lives on its own or it could be nesting . if i was you id watch for it to not be there or scare it of and just put a mulch of slate on top as it will move on when it realises it cant dig any more .

It's likely to be a solitary ground bee of some sort - dont' worry about drowning it, just water as normal - if conditions get too wet, it'll just fly out of the way, or move somewhere else.

thanks for advice on bee much appreciated

your more than welcome . id worry about the bee myself .

If it is one of the species of bumble bee they will nest in all sorts of places. I found one in a container last year. Could also be, as Bamboo says, be one of the solitary types. Both types are pretty harmless and the Bumble bee only uses the nest for one year.

i was thinking about being nice to the bee to lol cutsandgraz
love the name lol