Appreciation post: that USGS sediment data from the Missouri River

I was digging into the USGS reports for a job we did near Sioux City last fall and found out the river there moves over 150 million tons of sediment a year. That number just blew my mind, I had no idea it was that massive even with all the dams slowing things down. Has anyone else stumbled on a stat like that that made you look at your site completely different?

2 comments

2 Comments

paul11717d ago

Over 150 million tons of sediment a year" - is that really all that wild though? I mean the Missouri drains like half the continent, so it's got to move some dirt. The dams probably hold back way more than that, so imagine what it was before they put them in. I think people get hung up on big numbers without thinking about what they actually mean in context. It might be a lot for one river, but spread out across all that drainage area it's not exactly shocking.

john43017d ago

Yeah, @paul117, you nailed it with "spread out across all that drainage area it's not exactly shocking." I mean, think about it this way. The Missouri drains over 500,000 square miles. So if you do the math, 150 million tons works out to like 300 tons per square mile per year. That honestly sounds pretty tame for a big river system digging through soft prairie soil. In the Mississippi Delta, they've measured some spots losing over 100 feet of land in a century just from normal sediment load. So when you put it that way, 150 million tons doesn't seem like such a crazy number at all.