[Lawn Lad]

The picture shows the type of cobblestone driveway that we need to patch and repair. There is an area that has heaved, areas that are sunken, some bricks are sunken/cracked or deteriorated all together. I believe the cobblestone is a sandstone based on the way that some pieces have fractured or deteriorated.

Last year we buried 20' of 3.0" schedule 40 PVC under a section of the drive to run an irrigation pipe and wire through this spring. When we dug this area we found a green concrete/mortar bed that the cobbles were set in. The cobbles are of varying thicknesses. We reinstalled the cobbles on a bed of compacted limestone and then swept #10 screening in the joints. The trench area has sunken slightly, noticeable to the eye.

I'm wondering what we need to do in different situations:

Sunken cobbles: can we extricate and simply raise and reset? If so, with what material? Would limestone work?

Pot holes: Much like one sunken cobble, there are areas where five or six are lower and have created areas that need to be raised.

Heaved area: We were going to excavate and install a new base and relay about 120 sq ft in this one area. What type of base? Wet mix or dry lay?

Adding stones to the edge of the drive: In a couple of areas around the circular drive people are driving onto the lawn (creeping bent - looks better later into spring). We were going to widen the drive by 18" to 24" along two stretches. We'll obviously excavate back, but what base to install new stones on? Similar I'm sure to the heaved area above.

Thanks for input. This driveway in total is over 20,000 sq ft and we'd like not to make a monumental project out of repairing/maintaining it. But we only want to do our repairs once. There is an area along the length of the drive where wheel ruts are beginning to form, so this may be a project for future years.