I’m concerned about the stability of the upper spillway. The photo in 2175 shows water springing from beneath the slabs upstream from the blow out. While back erosion from the blow out seems to have stabilized, new problems are appearing upstream from there. If the spillway begins to break apart near these springs it will have to be shut down PDQ. It takes time to shut down, which will be a constraint on how much flow they can risk (too long a shut down period could be a big prob.). I hope there is a slow snow melt.
What you might be seeing are the sandbags strewn across the spillway near the top to direct the flow down one side only.
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