One good thing was that the small channel I had dug several years ago appeared to have helped a little bit in diverting some of the flow from my yard down to a channel which empties out into the street. I plan to go out there and fortify my civil engineering works this weekend to insure that any future rain events will pour out into the street and not into my backyard.
About the only "severe" damage to report was Boot Kitty's grave which I had carefully lined with stones is now completely buried in sand. I shall let it be.
Here are some pics of the damage.
Fur Central is on the right. There is a diversion channel to the left of the neighbor's house. That's where flood waters SHOULD go. Note the downcutting was about 4 feet.
The "delta" of sediment which was deposited in back of Fur Central.
These are the massive channels carved through the sand of the mesa which eventually flowed into the neighbor's house.
Here is a close-up of one of the channels. Kitty for scale.