I think the “rock dump” is for the emergency spillway, to fill in the gulleys and channels just below the spillway rim. I don’t think they are attending to the main spillway at this time, and are content if it remains stable.
Not sure about “700 feet”. The emergency spillway is 1700 feet long, laterally, and maybe that’s what you refer to. The “height”, by some measure, of the dam is 900 feet, so maybe the main spillway “hole” is 700 feet below the spillway rim. Obviously, I’m not sure where that figure comes from.
I blame the “news” for being mindless in these matters. They just spew out statements of all kinds which seem to be stamped with a confused history of acquistion. “All news is fake news.”
Personally, I think, a be prepare to flee warning, should have been sent out last Thursday... I think it was horrible to have thousands flee on a moments notice without having time to pack up meds, change of clothes, necessary documents, etc.
I got my 700 + number off the weather channel today. Tallest earthen dam in US. I have seen photos of that reservoir where the water level was darn near dry. That drying out changes the compactness of the dirt holding water over time.
As per “dutchsinse” the earthquake predicting channel on youtube, if you check the googleearth height above sea level, the dam top is at 900 ft, and the stream at the bottom is at 200 feet, for a drop of 700 feet. The river then further drops to either 28 or 20 feet above sea level at Sacramento. (I can’t remember, but you can check googleearth.)
As per “dutchsinse” the earthquake predicting channel on youtube, if you check the googleearth height above sea level, the dam top is at 900 ft, and the stream at the bottom is at 200 feet, for a drop of 700 feet. The river then further drops to either 28 or 20 feet above sea level at Sacramento. (I can’t remember, but you can check googleearth.)