Plumbing a dishwasher in a garage. what about the drain?

[rodneyja59]

I have cold water supply from the cold tank in the house, in the garage already but do not have access to a drain. The only access I have to a "drain" would be run the outlet of the dishwasher into the downpipe of the guttering that comes off the flat roof of the garage.
Can I do this or would I have to make an open vented drain outside besides the downpipe and join the drain and the downpipe together underground?
thanks

 

[breezer]

a garage will have a soakaway, not a drain, you will need to taake your outlet to main drain, in time a soakaway will clog up with debris / soap etc

 

[rodneyja59]

Not this one. Its the downpipe from the garage and the whole of the back of the house and it drains into the main drain (or as least lifting the nearest manhole cover and it drains into this). Which this is a spur off the big main drain.

a garage will have a soakaway, not a drain, you will need to taake your outlet to main drain, in time a soakaway will clog up with debris / soap etc