aav - erosion II {11 of 18}

The void under the concrete extends far enough upstream [ie leftwards] to be in line with the viaduct pier. [Camera is about a third of the way in on the next pier - Skew viaduct].
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A series of 18 images showing erosion and penetrations of the concrete cap, which has allowed scouring of the underlying fill leading to some significant voids and un-supported areas.