Storm drainage into closed bed

[John D]

My single home contains a downspout that empties onto the driveway and next to a bed that is against the garage. I intend on building a 9" high fieldstone wall on three sides of the bed (the fourth side is the garage) and installing shrubs, etc. Instead of allowing the downspout to empty onto the driveway, I'd like to direct it into the newly enclosed bed and allow a perforated PVC pipe to carry the rain water across the 20' bed. My question to you is...Is this recommended? Will it turn my bed into a slurry? Will it compromise my foundation or garage slab? I'd rather not dig under the new sidewalk or driveway to carry the water away from my house. My plan seemed to be the simplest remedy. Can this be done or am I better off avoiding worse-case-scenerio by allowing it to dump onto the driveway?

[84-1093879891]

I can't say how effective it would be without knowing the nature of the site, John. If you have a free-draining soil, then the planter bed may be able to cope, but then again, I don't know the area of roof that is being drained, or percolation test data for your area.

In the UK we prefer soakaways or leach fields (which is more or less what you're proposing) to be at least 10 metres away from the property to avoid potential problems with the foundations and/or damp. Things may be different in your part of the world, but I have no experience of practices outside Britain and Ireland.

Also, from your description, it sounds as though you will be piling up earth against the garage wall. This, too, is something we would not do in the UK/RoI.

If you discharge directly onto the driveway, where would the water run to? Back to the house or out to your 'sidewalk'?