To understand the Rio Grande between Bosque del Apache National Wildlife Refuge and Elephant Butte Dam you have to understand how rivers and mud move.  

Elephant Butte Lake is currently more than 100 feet below its conservation pool. For the river, this means it has 100 more feet to drop before it hits the lake, loses all of its energy and starts dropping sediment.   

For us, since we want to paddle canoes, that is a good thing. The more the river drops the more energy it has to carry sediment and the more cutting it does. The deeper it cuts, the more the water is concentrated, making it easier for us to find a channel deep enough to float a canoe. 

But if you want to have flows for maintaining a flood plain, that cutting is exactly what you don’t want. With the river flowing at the bottom of a 10-foot bank, it rarely will have enough water to overflow and recharge the flat land it is cutting through. The two systems then become separated and the habitat for native species is lost.    

We just transitioned from where the river was rising, often overflowing and maintaining that habitat in the refuge, to where it is cutting down. That exact transition point, just like the delta, is determined by the elevation of the lake, some 50 to 70 miles away, depending on how full the reservoir is.  

Unfortunately for the railroad, its bridge is well upstream of that transition. The bridge I floated under was raised 9 feet in 1930 and another 12 feet in 1943. Since then, the riverbed has continued to rise and now locals can rate some floods as “steel high” aka the floodwater laps up against the bottom of the bridge.   

Judging by the logs jammed into the steel support beams and the fine sediment mixed in with the rust, it looks like this happens fairly regularly. 

Either way, we have lucked out again.  

This morning I was able to ride the peak of another small flood through the refuge. Erich joined me at the railroad bridge and there was just enough water in the late afternoon to get us into the trenched reach where we are now camping and hiding from the mosquitos. 

With a little more luck, rainstorms tonight will keep the river flowing and we will be able to hit the remains of Elephant Butte Lake by tomorrow evening.

See what it looks like:

Check out videos of the train track here and here. And take a look at the crazy quicksand mud here.

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