Disappearing Rio Grande

Once, water levels weren’t the limiting factor for rafting on the Rio Grande.  

“We never thought there would be a day when we could not put a big old raft on the river and do whatever we wanted,” said Mike Long, who has been a river guide on the Rio Grande since 1986.   

Now, every time a client calls to book a trip two weeks out, Long has to do a song and dance explaining that they can’t commit to any particular reach because there might not be enough water.   

The challenge is that the steady flows have fallen away but the flash floods have not. As a result, the river still gets massive dumps of sediment, but does not have the continuous flow to carry it out and maintain the broad river channel.  

“You used to be able to go down the river and get out to pee whenever you wanted to,” said Jeff Renfrow, who has been working on the Rio Grande since 1988.  “Now you can’t. The cane has turned the river into a drainage ditch.”  

Without the steady flow to haul out the sediment, vegetation has been able to creep in over the riverbed, Renfrow explained. Once it is established, the vegetation traps sediment. The worst is the giant cane, an invasive species from the Nile. It grows tall and fast and the thin stalks are perfect for trapping the mud of the floodwaters.   

The end result is banks of mud 30 feet high, which sit on top of the old, broad cobblestone river bottom.    

Renfrow now augments his work as a river guide helping teams of scientists and laborers from both countries to monitor the status of the cane and conduct massive herbicide applications to try to kill it.  

The World Wildlife Foundation and Coca-Cola are the big supporters of the work.  

It’s all one big experiment to see if it is possible to bring back some of the old Rio Grande. The results could not only increase habitat for native species but may also increase water delivery to downstream users.   

The cane is now so thick and strong that it can hold flood waters and create its own reservoir. The stagnant water allows the cane to keep growing through the dry season and be ready to capture even more sediment during the next flood.  

As we have paddled from Presidio, we have already seen how the cane has taken over the riverbanks. Over the next few weeks we will see even more of the work Renfrow and others have done. 

“We don’t know yet if it will make a difference,” Renfrow said. “But we are working with people who have that as their goal.” 

I just hope I can find enough places to pull over and pee.  

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