Would be interesting to know all the cool stuff found at the bottom of the lake
Gold
Odds are there is a bit of it down there. I had a friend who lived above one of the arms on an old gold mine property. Lived in the mine office which was converted to a house. Still had side by side stone/gravel sluices on the seasonal creek outside the mine entrance. They'd dump their diggings in there and wait for a rain with the water directed down one side, sluice for awhile, then switch sides and pick the gold from the first side.
So I have no doubt there's likely a bit down there at the bottom of those arms of the reservoir. Likely not far from wherever a creek empties in.