Could there be artificial tributary created to prevent flooding towns?

Yes, but It would have to be about the size of the Mississippi. No sense in wasting all the space during normal years.

The current flooding is not a surprise to anyone involved, especially the people with flooded homes and farms. Floods happen. You work around it.

I didn’t know Mississippi is not a surprise. But why would it need to be the size of whatever river is concerned? It would only be for the excess right?

It’s possible, and such measures have been done, but it depends on the details of the place and what people have built where.

@Zaku ”...such measures have been done” Where? I would love to read about it.

@flo But why would it need to be the size of whatever river is concerned? It would only be for the excess right?

Yes, you are correct, I was exaggerating (AKA wrong)

But it is not a surprise. For example, the Morganza spillway has been in the news. It was built for exactly this scenario. It was designed to flood the area which is being flooded.

The Mississippi is already an artificial channel. If the US Army Corps of Engineers were not wrangling the waters, the river would have bypassed New Orleans long ago and washed Morgan City into the sea.

I would love to read about it.

I think you might really love this book.

The Control of Nature by John Mcphee
McPhee’s bestselling account of places in the world where people have been engaged in all-out battles with nature. In Louisiana, the U.S. Army Corps of Engineers has declared war on the lower Mississippi River, which threatens to follow a new route to the sea and cut off New Orleans and Baton Rouge from the rest of the United States…

@jaytkay It was designed to flood the area which is being flooded.
I thought the tributary was about taking the excess water toward the sea, not flood an area as a sacrifice.

Apologies for the pedantry, but tributaries are upstream, they conTRIBUTEe to the big river. The Ohio is a tributary of the Mississippi, not vice versa.

But yes, I understand your question.

And yes, they could build big dry canals to carry the excess water in flood years. But the expense and waste of land are not worth it.

In Southern California they do exactly that. There are “rivers” and “channels” and “reservoirs” which are dry 90% of the time. When the big rains arrive, they fill up.

But the amount of water in So Cal is tiny compared to the Mississippi. Trying to completely control or prepare for Mississippi floods is like trying to completely control and prepare for hurricanes and earthquakes.

PS Regarding So Cal rivers – If you’ve seen Terminator 2, you’ve seen Arnold Schwarzennegger riding a motorcycle in the Los Angeles River

And if you know musicals, here’s the LA River in Grease.

We could… I guess… and if we had started in about 1994, we could have been ready for this flood. Also, that would cost an enormous sum of money; would you want to raise taxes for it or just add it to the deficit?

Google Floodgate, Weir, Flood Bypass, Flood control channel, etc.

@jaytkay thanks, for the reminder re. the word “tributary”. I don’t know what the word should be.
@laureth It is not tax money that helps the people/comminity during the crisis? I guess it depends on the region of the world. Anyway if it keeps happening, the cummulative cost (the long term/the indirect cost, healthwise otherwise) is huge too. If it was done decades or a century ago…It gets done once right?
@Zaku Thank you. If you have read it already, Where does the water end up? In the sea?

Most diverted water would go to the same place the river goes – in most cases, a sea or ocean. Some water also goes (soaks) down into the earth, but in the excess of a flood, the ground tends to be saturated.

@Zaku thanks