
The trick to this job was to avoid the underground irrigation pipe that runs across the back yard. When we got close we had to skip a few feet of DitchWitch-ing and dig by hand. Just for fun and a bit of exercise I got in there myself and did some digging and pickaxe work. We found an 18" diameter concrete pipe exactly 18" below grade (so 36" to the underside). Since additional clearance is required for the electrical lines, we had to dig down 48" to clear the bottom of the pipe before laying the conduit.
Brian also used the DitchWitch to trench in the shallower (12") runs for the low voltage landscape lighting.
City of Phoenix should be here tomorrow to inspect, then we can backfill and be ready for the next steps. Meanwhile the dogs have an obstacle course to run every time they go outside!