Kitchen plumbing question

[GruffaloStick]

I posted a few days ago about my stinky dishwasher, it was kindly pointed out that the issue is probably with the drainage and we need a p waste trap fitting.

DH took a look and thinks the waste pipe is too high to fit a trap but agreed this is definitely why we have an issue.

Does anyone know if there's a way around this or if the only option is to create a new waste outlet lower down?

We're FTB, the kitchen is approx 2 years old which the previous owners had fitted by B&Q

Picture would help. Waste pipe highlighted.

loop the waste hose up so that it touches the bottom of the worktop, and fix it with a bit of string or a cuphook or something.

When the plug is pulled out of the sink, the water in the waste pipe can rise up to about the level of water in the sink.

So looping up the waste hoses prevents water running down them and into the appliance.

your plumbing design is not very good. The waste hose is attached below the water level in the "trap" and it looks to me like waste water can freely flow between dishwasher, washing machine and sink.

have a look at what's to the left of the unit in your photo

p.s.

Look up the "first rule of plumbing"

Thanks Pigletjohn, I'm guessing it isn't "don't talk about plumbing"?!
We've already looped the dishwasher hose up (the grey) should I loop the main waste hose up too (the white)??
Yes the plumbing is awful, as are most things we have uncovered unfortunately. It has been a steep learning curve.
To the left of the picture is the drain for a small half sink

Also, there's no washing machine, that's on a separate waste pipe in the utility room, thankfully

where does the white one go?

if yours is a modern house, I expect there is a soil pipe, running vertically in a corner of the kitchen (and the bathroom above) and partly boxed in.

The kitchen fitters might have hidden some pipes in the gap behind the units. Can you see into the corner?

Will that shelf, under the sink, come out?

Yes the shelf will come out but the cupboard completely boxed in.
The white appears to go to a pipe outside the house. It's a Victorian terrace

Meant to add. We think there was originally a waste pipe lower down that has been cemented over, not sure if you can see the 3 cemented bricks below

Oh, that's easy then.

I'd suggest you (or a plumber) remove the shelf and hideous mess of pipes, and fit a simple U-bend, to exit the wall lower, with an appliance connector just under the sink plughole, or (better) an standpipe and trap for the appliance, exiting the wall separately.

Examples:
www.screwfix.com/p/mcalpine-appliance-trap-white-40mm/95241

www.screwfix.com/p/floplast-washing-machine-trap-white-40mm/18640

You may be shocked to learn that kitchen fitters might not be good plumbers (or good electricians, or good plasterers...)

Thank you PigletJohn. Very helpful, I scoffed a bit at easy though!
I'll get DH on the job this weekend, we're hoping to save costs as much as possible.
I guess we'd have hoped it would have been done to a better standard, we knew they weren't good plasterers after seeing the state of the kitchen wall
I'm guessing we need to cut through the back of the cupboard and drill through to fit another waste pipe?
Sorry for what might seem like obvious Qs we really are learning as we go. Advice genuinely appreciated