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COLORADO PLATEAU 
NAVAJO SECTION 
SECTION D 
The Navajo Section,in the south cenral part of the region, 
covers about t of the region and is its largest subregion. 
It is an area of widely varying conditions, ranging from 
high, forested mountains to barren deserts. Culturally it 
varies from the rural slums of the Navajo Reservation to 
booming oil, gas and uranium towns. 
RELIEF AND DRAINAGE - The subregion is composed of many high 
isolated sandstone plateaus, surrounded by retreating escarp 
ments and rock terraces, and deeply cut by canyons. Great 
dome uplifts have elevated some areas creating isolated 
mountains. Between the plateaus and the mountains are broad 
basins, which vary from high valleys below the plateau scarps 
to low deserts. The basins are drained by dry washes where 
flash floods are a constant hazard in summer. The upper San 
Juan drains the northeast corner of the subregion and sup 
plies the only stable source of irrigation water. The Chama 
and Little Colorado drain the balance. 
SOILS AND VEGETATION - The soils of the high plateaus are 
relatively undisturbed and are protected by a forest cover, 
but the soils of the lower plateaus and basins are eroding 
badly due to many years of overgrazing. Much of this area 
is at a low elevation with a semi-desert climate, and there 
is a precarious moisture balance between what is adequate 
for drought and alkali resistant shrubs and complete desert 
conditions. Many of the lower areas, like the Painted Desert, 
are without any vegetation and are eroding severely. 
RURAL CULTURE - In recent years the timber resources of the 
high plateaus have been developed to supplement unreliable 
returns from livestock raising and farming, and modern saw 
mills and lumber yards can be found in a number of places. 
In the higher basins, where rainfall is adequate, the range 
shrubs have in places been plowed up and the land converted 
to grass or dry farming. Although much of the subregion is 
unsuited to any form of agriculture, there are many irriga 
tion projects where water from the upland snowmelt is im 
pounded. Oil, gas and uranium development is increasing and 
oil rigs and pipelines appear on otherwise worthless lands. 
Coal mining is important in the northern and southern parts, 
where carboniferous strata turn up to the surface. 
UhBAN CULTURE - There are only a few towns in this sparsely 
settled subregion. They are of two types, the rail and high 
way towns, such as Durango and Gallup, and the irrigated val 
ley towns, such as Farmington and Aztec. 
TRANSPORTATION - The main line of the Santa Fe R. R., para 
lleled by US Hy. 66, crosses the low basins on the southern! 
edge of the subregion, and several improved highways branch 
off from this. Narrow gauge mining railroads radiate from 
Durango. Unsurfaced dirt roads,leading into the high coun 
try, are poor because of the adobe clay soil, becoming impass 
able after rains. Travel in the back country is by horse or 
4-wheel-drive vehicle, and the covered wagon of a century 
ago is still the standard mode of travel in the hinterlands. 
Rough trails provide the only access to many areas. 
Fig. 1.2 Typical view of the Navajo Lection. It has isolat 
ed mountains, such as Navajo Mountain in the distance, high, 
cool, forested mesas cut by canyons, such as Black Mesa at 
the left, and hot, semi-desert basins. The limiting factor 
is water and it is carefully conserved. The earth tanks in 
the foreground catch summer rain for stock water, and water 
is collected in Aayenta '/.ash to Irrigate a small acreage. 
Navajo Reservation at Kayenta, Arizona. October 1947. 
GVII-86 PHOTOGRAMMETRIC ENGINEERING