As we have excavated the central back yard, we piled up the dirt on part of the Bottoms that has already been excavated.
But as we got more and more of the central back yard dug up, and particularly after lowering the main irrigation water line, it seemed we could move the dirt back to where it will eventually be. So we took some time to dig all that dirt up out of the Bottoms
and move it to the ditches that were the result of our digging, levelling off the back yard, more or less.
This "level" is still several inches below where the lawn level will eventually be, still leaves some substantial ditches, adjacent to where we will be continuing to dig.
But it gets things to the point that we will begin to cover up things we may eventually need to find, specifically with the underground irrigation system.
The control value for Zone 5, which controls the sprinklers for the Iris bed and the Herb Garden beds, is just off the sidewalk. It's about 7 inches from the sidewalk and 11 inches down from the level of the sidewalk.
The main irrigation water line runs way down at bedrock, until it gets to the River of Rocks, where the River of Rocks terminates at the back sidewalk. Then it comes up to a more "normal" depth and continues around the house. It rises up to 8 inches below the level of the River of Rocks, and the sidewalk, and is 13 inches away from the sidewalk. (It basically runs parallel to the sidewalk, 12 to 13 inches away from the sidewalk, for the entire length of the house.)
The valves for Zones 6 and 7, which will be used to water the central backyard and the Bottoms (respectively), and buried in the Bottoms, just off of the Rock Retaining wall. One of the rocks in the Retaining wall is more or less rectangular and sticks up an inch or two above the top of the rest of the wall. From the top of that rock, it's 21 inches down to the valve covers and 14 inches away from the Retaining wall itself.