Washing machine - Extension of waste pipe

[se99paj]

I'm currently helping the my landlord fit a kitchen, unfortunately due to a few minor errors we are going to move the washing machine from one corner of the kitchen to the other corner. This will basically make the kitchen look much better and will make it easier to fit together.

But we do have one problem, currently the washing machine is situated next to the sink, and the waste and inlet pipes are nearby, if we move the washing machine to the other corner there are no pipes, so the existing ones will have to be extended a length of 3m.

I know the inlet pipes won't be a problem as they are under pressure, but I'm worried about the waste water pipe. Ideally the waste water pipe will go from the washing machine down to floor level, behind the legs for the new cabinets, then when it gets to underneath the sink, the pipe will rise up about 0.5m, and connect to the new U-bend.

Will the washing machine be able to pump the water this way??
Would I be right in assuming the water will become stagnant in pipe?? Would this be a problem??

 

[nstreet]

Water loves to flow downhill, washing machine waste isn't under that much pressure, so your uphill part may cause you problems. Why not just run the new waste outside?

 

[se99paj]

We could plumb it outside but this would still require a 3m length of pipe to get it there, its a bit tricky to explain but the house is terraced and there are only really two walls out of the kitchen we could plumb it, unfortunately one is blocked by a doorway, it could work with the other one.

I suppose as long as the pipe is at a gradual slope , the water will still run down it. I don't think the landlord was planning on drilling any massive holes into the wall but if there is no other way.