Running rain gutter drain line under sidewalk
 

I have a rain gutter whose downspout empties onto my driveway resulting in black mildew on the concrete. On other downspouts I have extended the lines under garden beds and out into the lawn. However, for this one, I would need to go under the front sidewalk. Is there a special tool or an easy procedure that would allow me to dig a tunnel under the sidewalk large enough to run a gutter extension line?

Attach your garden hose to a piece of PVC, turn on the water and prod the pipe under the sidewalk.
Here is how one guy did it, I don' think you need that special kit.
[ame]http://www.youtube.com/watch?v=3Kv9x8bAWVM[/ame]
I couldn't get the url to show up. Do a Google search on "tunnel under sidewalk"

Dig a hole about 16 inches deep on each side. Take a piece of one inch PVC pipe and insert your hose inside the pipe. Turn on the water full force, start the pipe under and keep working it letting the water pressure wash a hole through. Make it big enough to place the drain pipe under and your done. Make sure you go at least a foot below the walk to prevent the side walk from cracking down the road.

I did a garden hose with PVC pipe, just try to keep it level, or at the other end it could be 3' down on the other side.

Thanks to those who posted. I'll give it a try. Sounds like I will need to move some shrubs to get clearance for the PVC pipe. It seems like I woud want to use two PVC pipes - a large diameter one that will remain in the tunnel and keep the tunnel from collapsing and the 1 inch one to run through the larger one and to clear the dirt out with. Is that right?

Of course the whole process could be stopped for good if I run into some of the rubble that the contractors threw around during the building of my house. I couldn't believe the amount of large concrete chunks that I have found while digging in my beds.