Recent flooding in the Red River valley brings to mind the last major flood in my town. It was 1997, the same year of the last flooding in Fargo and Moorhead.
Houses had been built on the floodplain here in the late 1890's, before a dam was installed downstream on the Mississippi. After the dam was built, whenever there would be a rapid breakup of the ice on the river it would float down to the dam and cause a jam- if the snowfall had been high that winter, the water would back up in a hurry. After the last flood, the few remaining houses on the floodplain were removed, and the land was elevated about 4 feet. New houses were built (without basements) and the area is stable (at least until it floods 5 feet!)
In the Red River Valley, Grand Forks was devastated in '97 as well. After the flood they also removed all housing from the flood plain and rebuilt dikes to a much higher level. In Fargo and Moorhead they did not. The Red River flows North, to Lake Winnepeg and ultimately emptying into Hudson's bay. Until the spring thaw in Canada, the river is prone to backing up.
About every ten years there is a significant flood in the F-M area. Many of the homes which are threatened or have succumbed to the flood waters are newer, expensive homes, in exclusive neighborhoods. Someone approved their construction and financing.
I don't understand this.