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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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Jan. 16, 2015

Nice folks, Day 211

Octavio Acosta Martinez looks down at the Rio Grande from the land where he raises milk cows and grows vegetables. Photo by: Colin McDonald

Octavio Acosta Martinez spends most of his day along the Rio Grande tending to 15 milk cows and doing odd jobs on a 70-hectare farm just north of Matamoros.

He said he enjoys the river there. It is peaceful. He said the cartels don't bother you unless you bother them. They are like anyone else and are just doing their job.

That was good enough for us and we spent the day making miles. We are now less than 15 river miles from Brownsville. Keith got a surprise gift in the form of Tecate beer on ice delivered to the river side. He has never had such river side hospitality. But he was not surprised. The folks of the Valley are the nicest folks he has ever met.

Thank you, Samantha Moore and Elizabeth Heise of U.T. Brownsville.

It's going to be hard to say good-bye to this river.

Note: Colin's dissolved oxygen meter is not working, so that number is not correct.

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

Photos #

Samantha Moore delivered cold beer for Keith and doughnuts and water-quality-testing supplies for Colin. Both were thrilled by the generous hospitality. Photo by: Colin McDonald

There are only a few more drops between here and the Gulf of Mexico. After taking a bumpy ride over this dam, Keith and Colin camped just around the bend. Photo by: Colin McDonald

Camps along the river usually involve steep climbs up sandy river banks. Keith cleared this path with hand clippers and cut steps with a shovel. Photo by: Colin McDonald

Measurements #

21.0

Air temperature (°C)

1683.0

Conductivity (µS/cm)

2.0

Depth of Measurement (meters)

0.0

Dissolved oxygen (mg/L)

None

E. coli colonies per 100 ml

7.6

pH level

0.5

Secchi disk transparency (meters)

20.0

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: 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.

Check-ins #

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	10:09 a.m.	26.02778	-97.67343
#2	12:24 p.m.	26.01183	-97.64233
#3	1:11 p.m.	25.99767	-97.62845
#4	2:16 p.m.	25.9954	-97.63272
#5	3:30 p.m.	25.95852	-97.59708
#6	5:13 p.m.	25.94847	-97.56586

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About

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.

Contributors

Colin McDonald

Reporter

Erich Schlegel

Photojournalist

Jessica Lutz

Photojournalist

Mike Kane

Photojournalist

Jessi Loerch

Project Editor

Barbara Hosler