Will I have to keep this if I get my patio redone?

[Soopermum1]

It's a pain in the arse

My MIL has a similar exposed drain taking drainage from kitchen sink and dishwasher.
It's not clean water, it's manky and greasy. We give it a good clean out every 6 months or so.

@Soopermum1

The extension was built in 2005 so there was nothing there before. No evidence of damp, good point re the water flowing away from the house, I think the current layout has that covered

So if the drain and gully are modern plastic, it is quite easy to pull off the top and fit a different type. There is a push-on joint.

But modern practice is to put the waste pipe through the grille so it should not be splashing or overflowing.

BTW greasy water from a kitchen sink can happen if the homeowner is pouring fat down the drain, or washing greasy grill or roasting pans. Fat should be wiped out with kitchen roll, or poured into a can and binned.

Washing soda Crystal's are good for cleaning grease from drains.