The chart shows average monthly elevation rather than daily elevations. Perhaps a scatter chart would have been a better choice than a line chart, which could be misleading.
The lake elevation data in the graph in post 3560 is based on data from https://cdec.water.ca.gov/cgi-progs/queryMM
with parameters: Station ID:ORO Sensor Number:6 Date:04/17 Span:144
Which provides the daily lake elevation in feet to two decimals places. The daily elevation values were averaged for each month and rounded. The same data is in a table in post 3549.
I sought to identify periods of low precipitation and elevated lake levels to help determine whether the occurrence and size of the green area correlates with precipitation or with raised lake elevation.
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Data in tabular form here.
What does align with the precipitation is the cooling of the zone 3 cobble shell's effect allowing the subsurface percolation to wick to the surface. Essentially, the furthest reach of the broad seepage percolation into the Zone 3 fill is what meets the wet area surface. There is more water behind and deeper that is in this broad seepage. That is what is causing the erosion channels (deeper seepage just under the surface).
Oroville's strong heat, low humidity, winds, and the huge heat sink of the mass of the southern facing rock face cobbles, boulders, gravels effectively neutralize the wicking/seepage at the surface in summer. This neutralization goes to a depth to the heat penetration of the infrared absorption & the atmospheric temperature base.
This is a key reason why DWR has been puzzled over the variances.
They DO know there is a water source. I have new documents that have stronger notations on their investigation(s).
The other key piece that throws off a correlation to this mid-slope area is what keeps DWR from putting the last pieces together --- that is an "erosion soil/silt/sand semi-pervious "shelf" has formed from the migration of internal erosion. Normally, seepage past the core would be caught in the drain zone. Since there is an issue where seepage gets past the core (whether its arguable from the hillside or core) the puzzle would be how does the water flow in a horizontal formation to create the outer horizontal seams of the greenage wet areas. This can only be facilitated by an original consolidation "shelf" that erosive flows have subsequently deposited soils/silts/sands (zone2 & core) upon. These SAME materials are ported to the surface where this material forms the growth medium the plants feed off of.
Post 3,546 clearly demonstrates this internal soils porting to the surface in the two large soil patches (after a strong seepage differential settlement stage in the early dam operation). These large soil patches have since been washed away and there is no green patches or wet areas there today. BUT the process never "sealed" or stopped in the left abutment. Now the Green Wet area has matured to a full soil patch and feeder of internal waterflow. It is just that the flow has internal percolations & the flow has an "outer" finger of reach to the surface that can be neutralized to some inches below the surface by the hot Oroville weather conditions.
DWR knows there is a water source. They are not telling the public. They are trying to figure it out thinking it is coming from the hillside. The DWR engineer, at the first town hall, let it slip as to what DWR really thinks. They believe its from a natural spring flowing from the hillside into the zone 3 fill. However, this is bad PR to admit this. That is why the new message is "rain falls... grass grows". They are burying the "natural spring" statement as this wouldn't be good for an earthen dam to have penetrating it.