Natural Resources Conservation Service
6200 Jefferson NE
Albuquerque, NM 87109
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News Release
Contact: Barbara Garrett, public affairs specialist
June 6, 2006
(505)761-4406
CONSERVATION AGENCY URGES AWARENESS OF COLLAPSIBLE SOILS
Have you wondered while traveling between Albuquerque and Santa Fe why the road
suddenly becomes bumpy and wavy near Algodones? Have you noticed the same thing on
stretches between Espanola and Taos? Ken Scheffe, NRCS state soil scientist explains the
reason in a paper he presented to the Geological Society of America earlier this fiscal year.
The culprit is collapsible soil.
Collapsible soils are common throughout the Rio Grande Valley in central New Mexico.
Significant losses have occurred for those who unknowingly build on collapsible soils as
well as significant cost increases have been incurred by those who are aware of the hazard
and take remedial measures to develop the site.
New Mexico is undergoing dramatic urban development and expansion of it cities and
communities beyond the Rio Grande Valley terraces and flood plain onto the alluvial fans
from the mountains. The alluvial fans upon which urban development is occurring also
happens to be the environment of collapsible soils.
The arid climate seldom wets the surface soils to a depth of a more than a few centimeters.
Intense very brief thunderstorms occurring during the summer monsoon season are greatly
intensified by the uplift of mountain ranges. Resultant flash floods carry large sediment loads
from the sparsely vegetated mountain foothills onto the alluvial fans. The highly porous
structure of the mudflow or debris flow remains intact and is often further buried. Calcium
carbonate in the soil provides cohesion of the clay and silt minerals to sand grains giving
considerable strength to the soil when dry.
The collapse of these soils is induced when water is intro