Disappearing Rio Grande

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Why Follow the Rio Grande

by Colin McDonald | Feb. 11, 2015

The Rio Grande is disappearing. Demand for water is growing as snow packs shrink, rain patterns shift and average temperatures rise faster than they ever have in the past 11,000 years.

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Get it out of your system, Day 130

Colin McDonald talks with U.S. Sen. Rob Portman via a satellite phone while Dan Reicher listens in and Peter Serrurier looks on. Photo by: Fred St. Goar

One week and 37 years ago, an expedition of undergraduates from Dartmouth College passed the campsite we are using tonight.  

Dan Reicher was the biologist on that expedition. He brought along a copy of his journal from the 1977 expedition to share with us as he revisits the river. Rob Portman was a liaison with locals and went on to become the U.S. Senator for Ohio. He could not make this trip because of his work campaigning for his fellow Republicans. But he called in via a satellite phone so he could be part of the trip.  

For the most part, the diary entries and stories told by Portman do not seem dated. There was trouble with the rapids in Mariscal Canyon and the supply canoe flipped. Some tourists from Kentucky told Reicher to not rush into marriage unless he was done with such adventures. There was concern about safety along the border. 

But overall, there is less water to float boats and the border itself has changed. The ferry to the town of Santa Elena is gone and the city has all but disappeared, it has been on the banks of the Rio Grande for 300 years. That’s where Reicher met the advice-giving tourists. The border was closed after the terrorist attacks of Sept. 11. Residents were cut off from the income stream from tourists and from the stores of Big Bend National Park, which were the only local place to buy necessities.  

Portman said the trip made him sort of fall in love with the Rio Grande and especially the border. He wrote his senior paper about the region and came back to work as a ranch hand. He later returned to the same ranch to spend his honeymoon on the Rio Grande and then later brought his children. The kayak he used on the expedition hangs in his office.  

“I always tell the story that no one would be crazy enough to do it again,” he said. “I’m glad to be talking to someone who is.” 

When the issue of the border wall comes up, especially in remote areas like where we are now, Portman points out it would not work.  

“People say we need a wall across the border,” he said. “I do believe in control of the border, but having a wall does not make sense to me. It would create a lot of hardship in a lot of communities.”  

That comment brought a sigh of relief among the river guides and river advocates I’m traveling with. Then Portman made a very divisive comment.  

“My first love is still canoeing,” he said.   

The canoe may not have flipped if it had not been loaded down with the gear from those in the kayaks. It is hard to forget adventure like that on the Rio Grande.  

Some things never change.   

To comment on this post or ask a question, please visit the expedition's Facebook page.

Air temperature (°C)
Conductivity (µS/cm)
Depth of Measurement (meters)
Dissolved oxygen (mg/L)
E. coli colonies per 100 ml
pH level
Secchi disk transparency (meters)
Water temperature (°C)

What do these numbers mean?

As they travel, Colin and Erich are taking water samples for the following periodic water quality tests. In partnership with The Meadows Center for Water and the Environment’s Texas Stream Team Program at Texas State University, the results will be added to a public database it helps maintain for research and monitoring water quality.

Air/Water Temperature
Temperature impacts everything from the amount of oxygen in the water and the metabolism of aquatic species to how easily compounds dissolve. Most species can tolerate slow seasonal changes but can go into thermal stress or shock when temperatures change by more than one or two degrees Celsius in 24 hours.
pH Level
The pH scale measures water’s acidity and runs on a logarithmic scale from 1.0 to 14.0, with 7.0 considered neutral. Anything below 7 is acidic and anything above is basic. A pH range of 6.5 to 8.2 is optimal for most organisms.
Dissolved Oxygen
Oxygen is just as vital for life below the surface as it is above. The amount needed varies according to species and stage of life, but generally 5.0 to 6.0 milligrams per liter is required for growth and activity. Levels bellow 3.0 mg/L are stressful to most fish species and levels below 2.0 mg/L for an extended period of time will cause fish kills.
Conductivity levels depend mainly on how easily the rocks and soils a stream passes through dissolve. For example, high levels of conductivity are often found with water that passes through limestone and gypsum because it will pick up the calcium, carbonate and sulfate from those rock formations. However, discharges into a water body, such as a failing sewage system, can also raise the conductivity because of the presence of chloride, phosphate and nitrate.
Water Clarity
Turbid water can come from high levels of sediment or plankton. Both will block sunlight to aquatic plants and the sediments can carry pollution such as nutrients and pesticides. Low levels of turbidity may indicate a healthy and well-functioning ecosystem. High levels can be an indicator of runoff from eroding soils or blooms of microscopic plankton due to high levels of nutrients.
E. coli
E. coli bacteria are found in the colon of warm-blooded animals. If the pathogen is found in water it’s an indicator that fecal mater from humans, pets, livestock or wildlife is also present and may pose a public health threat. For drinking water the standard is to have no E. coli. But almost all non-treated water has some E. coli in it and at low levels it does not represent a substantial health threat to those who swim or wade in it. The Environmental Protection Agency has set the water quality standard for these types of activities at 126 colony forming units per 100 mL.
Secchi disk transparency
The Secchi disk is a plain white, circular disk used to measure water transparency in bodies of water. It is lowered into the water of a lake or other water body until it can be no longer seen. This depth of disappearance, called the Secchi disk transparency, is a conventional measure of the transparency of the water.

While making his way to the Gulf of Mexico, Colin will be periodically activating a device that uses satellite technology to share his current location. Use this map to see where he traveled on this day.

Check-In Time of Check-In (CST) Latitude Longitude
#1 11:04 a.m. 29.15581 -103.59872
#2 12:07 p.m. 29.1499 -103.58014
#3 3:10 p.m. 29.11993 -103.52124
#4 3:58 p.m. 29.0959 -103.48553
#5 4:16 p.m. 29.09288 -103.48315


To report on and understand the haphazard irrigation system the Rio Grande has become and the changes it is going through, Colin decided the best approach would be to travel the length of the Rio Grande by foot and small boat.

He knew it would give him a unique perspective on a river that few understand. It did require many long days of moving slowly and camping on muddy riverbanks, but Colin likes that sort of thing.

The benefit was it provided access to people who wanted to share their stories and experiences with the Rio Grande. Via Facebook and chance encounters, Colin made instant friends who opened their homes. They provided help from loaning their trucks to their cell phone contact lists to help tell the story of the Rio Grande.

The trip would not have been possible without their help, along with the dedicated assistance of David Lozano, Jason Jones and Daniel Dibona, who drove thousands of miles to get people and boats in place.


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