This house was up above the level of the flood waters. However, the riverbank washed away, and the house plunged into the river. There’s a flood control dam upstream that prevented the floodplain from flooding, but it doesn’t prevent the river for migrating.  Classic example of how homes and other structures might be safe from getting flooded by rising waters, but they may not be safe from the geomorphic processes during floods. This concept of high waters versus erosive waters is key to my work on flood hazards.

http://www.bostonglobe.com/metro/2017/10/30/house-washed-away-new-hampshire-river/2z9nl5sRBIHX9AQytx9DWP/story.html?event=event25&s_campaign=sm_gp&hl=en-US