Why Is River Silt Bad For Farmlands? [Mississippi Floods]

Factual Questions
21

This is an area that was for centuries seasonally inundated by the river, and since 1928 has been declared to be a potential subject of a levee blow.

I can understand the farmer’s viewpoint–a levee blow will scour rather than deposit–but they’ve been living on borrowed time for nearly 80 years.

22

The organic humus washes out and you’re left with a ton of sand. The humus collects at the drop out points of backwaters where the water sets and evaporates. Some places will collect the black humus, but many of those fields were washed by quick flowing water which takes away the humus. Think of all the sandbars in rivers.

Having dealt with ground that was under 3 feet of flood water I can tell you the following.

  1. I had a layer sand inches deep in many places because the humus floated away.
  2. I was left with a slick black 1/16 inch layer of fine organic material deposited on top of the sand at most when the stilled water evaporated.
  3. The ground was packed hard as a rock.
  4. The ground smelled like feet with jungle rot two years later when I dug up a new area due to the anaerobic bacteria in the soil which is the opposite of what productive soil has.
  5. There was a lot of pollutants in that water including a nice oil slick.

Many farmers from the same flood spent a whole year fixing their fields with earth moving equipment. Insured farmers still had to replant when the ground dried out and was plantable to get paid their settlement and some planted 3 times to never get a crop.