I saw this after I posted the other Trinity River link - the previous one, Goodrich, is below the dam.
http://ahps.srh.noaa.gov/ahps2/hydrograph.php?wfo=hgx&gage=rvrt2&view=1,1,1,1,1,1
Riverside, just above Lake Livingston. I'm sure the lake fills from many sources other than Trinity River above - it is a big reservoir.
Interesting...gpapa's links led to similar results....soooo....do we have a wind event here instead? Debris hitting something important? A wind driven seiche? The other watersheds feedig that lake are minimal...but if Lufkin and Nacadoches got hammered, and they are 50 and 75 miles north north east of there....
That's all I can come up with, the flow down the Trinity isn't very impressive.