PHYSICAL GEOGRAPHY OF UTAH
and Colorado rivers of the Colorado Plateau
Centrally located in the Intermountain West, Utah is bordered by all of
the mountain states except Montana and is often called the "Crossroads
of the West."
The state's centrality is important to the prosperity of the Wasatch Front,
Utah's core area, and particularly to the Salt Lake City metropolitan area.
The term "Salt Lake Empire" refers to the large geographical area
that comes under considerable economic and/or religious influence from Salt
Lake. The empire penetrates significantly into Idaho, Wyoming, and Nevada,
somewhat in Arizona, and is not of much consequence in either New Mexico
At 84,916 square miles or 54,340,240 acres, Utah is the thirteenth largest
state in the United States. Approximately three percent of the surface is
covered by water.
Rising to 13,528 feet, Kings Peak is the highest spot in Utah, and Beaver
Dam Wash in the southwestern corner of the state is the lowest point at
2,350 feet. Only the Uinta Mountains have peaks that exceed 13,000 feet,
and there are twenty-four of them that do. Three other mountains systems
have peaks that exceed 12,000 feet--the La Sal, Tushar, and Deep Creek Mountains.
The highest peak in the Wasatch Mountains, Mount Nebo, is 11,877 feet.
Utah's landform is divided among three major physiographic provinces: the
Great Basin or Basin and Range province, the Colorado Plateau province,
and the Rocky Mountain province.
The largest of the provinces in Utah is the Colorado Plateau. It has been
described as a land of layered, flat-lying sedimentary rock. The story of
the earth's movement and history can often be read in the tilt and erosion
of the layered strata. Within Utah's portion of the Colorado Plateau are
five national parks, six national monuments, a national recreation area,
and several state parks. It has one of the largest deposits of hydrocarbons
in the world--coal, oil, oil shale, tar sands, gilsonite, and natural gas.
It also has significant amounts of uranium.
Water is the most important agent for change within the Colorado Plateau.
The Utah section of the plateau is drained by the Colorado and Green rivers
and their tributaries. The plateau's varied exposed surface materials can
be spectacular in appearance. Utah's portion of the Colorado Plateau can
be further divided into the Uinta Basin, Canyonlands, and High Plateaus
The Great Basin, located mainly in Utah and Nevada, is the northern part
of the larger Basin and Range province. A large majority of Utah's portion
of the Great Basin is called the Bonneville Basin because at one time it
lay beneath ancient Lake Bonneville. The lowest part of the Bonneville Basin
(and of the Great Basin) is covered by the Great Salt Lake, a remnant of
the much larger ancient lake. The surface of the Great Salt Lake is about
4,200 feet above sea level; the Sevier Basin is around 4.700 feet in elevation;
and the Escalante Basin is approximately 4,900 feet.
It is believed that the mountains of the Great Basin are fault-block in
origin, the same as the Wasatch Mountains and the Sierra Nevada that border
the Basin. The mountains have formed along a generally north-south axis
and they have valleys or basins separating them. Both the mountains and
the basins tend to be from about 25 to 50 miles long and from 15 to 20 miles
wide. Many of the basins are self-contained, meaning that they drain internally
and are areas of water and soil accumulation.
Of the three major provinces, the physiographic province that covers the
smallest area in Utah is the Rocky Mountains, which is divided between the
Wasatch and the Uinta Mountains. This province is particularly valuable
to the state for the water, recreation, and minerals it provides.
The Wasatch Mountains follow a north-south axis from the Idaho border southward
to Mount Nebo near Nephi. They are a fault-block range that is structurally
similar to the mountains of the Great Basin. Water from Wasatch streams
has been essential to the settlement along the base of the range throughout
The Uinta Mountains are one of the few east-west ranges in the Rocky Mountains.
Unlike the fault-block mountains of the Great Basin and the Wasatch, the
Uinta Range is a folded anticline bordered by the Uinta Basin to the south
and the Green River (or Wyoming) Basin to the north. The Uintas offer excellent
recreational opportunities, but they are not as heavily used as the Wasatch
Mountains because they are more distant from population centers.
Climate and Weather
While Utah is widely perceived to be a desert state, and statistically it
is the second driest state in the nation, its climate, soils, and vegetation
are as diverse as are its landforms.
Utah has three climatic regions--humid, sub-humid or semi-arid, and arid--and
each region covers about one-third of the state. The high mountains and
plateaus are humid; the lower basins, valleys, and flatlands are often arid;
and the transitional places in between are sub-humid to semi-arid.
The arid region generally receives less than eight inches of precipitation
annually and has an annual evapo-transpiration rate often 30 to 50 inches.
The humid zone generally has eighteen inches or more of precipitation, and
its precipitation by definition exceeds the evapo-transpiration rate.
While most of the moisture in Utah is associated with frontal systems from
the Pacific Ocean, there is a period in mid- to late summer when convectional
rainfall is very important, particularly in the southern and eastern parts
of the state. During this time, moist air masses from the Gulf of California
or the Gulf of Mexico periodically enter the state. The moist air is unstable
and convectional processes frequently cause cloudbursts and flash flooding.
The heavy convectional precipitation tends to be localized, but in the narrow
canyons of southern Utah the danger of flash floods is high both from local
cloudbursts and from heavy downpours that might fall many miles upstream.
Thistle after the landslide and flood of 1983
Earthquakes and landslides are the two most serious landform-related natural
hazards in Utah, whereas floods, wind, fire, and avalanches are the most
prominent weather-related ones.
Earthquake danger in Utah is high because of the large number of faults
located in the state. The most significant of them from a natural hazards
perspective are whose slippage would affect the more densely populated areas
of the state. This makes the Wasatch Fault easily the most dangerous of
all because it is located near where the majority of the state's people
live and work. The Sevier Fault has had more earthquakes of a higher intensity
than the Wasatch Fault, but it affects fewer people.
An earthquake associated with a major movement of the Wasatch Fault would
cause great damage along the fault line. However, it might create even more
destruction in the valley below because of what is called "liquefaction"
of the earth. Liquefaction would occur if the shock of a major earthquake
caused the groundwater along the Wasatch Front to mix with the Lake Bonneville-deposited
alluvial soils in such a way that the soils would lose their ability to
support structures. This is what caused the devastating damage of the Mexico
City earthquake of 1985. Both Mexico City and the valleys of the Wasatch
Front are located on old lake beds.
Landslides and mudslides received much attention during the above-average
precipitation period of the 1980s. There were many such slides, and a few
of them were among the largest recorded in North America. It was reported
that the Manti Canyon slide of the 1970s, and the Twelve Mile Canyon slide
in Sanpete County and the Thistle slide, both in 1983, were respectively
the fourth, fifth, and sixth largest landslides ever recorded in North America.
Avalanches, along with flash floods, are the primary weather-related killers
in Utah. Almost every year snow avalanches claim several lives in the state,
primarily in the Wasatch Mountains.
Possibly the worst possible scenario for a natural disaster in Utah would
be a major earthquake when the ground in the valleys and on the slopes was
wet. This might produce the maximum possible damage from shaking, liquefaction,
Utah was still Mexican territory when the Mormon pioneers entered Salt Lake
Valley in 1847. It became a part of the United States at the conclusion
of the Mexican War in 1848. Brigham Young promptly announced an entity he
called the State of Deseret, a territory that included Utah, Nevada, western
Colorado, western New Mexico, almost all of Arizona, part of Idaho and Wyoming,
and a large area in southern California including the coastline from San
Diego and to about Santa Monica. It was some 265,000 square miles in area.
San Diego was to be the seaport for the state.
Washington denied the petition for statehood and the Utah Territory was
formed instead. The Utah Territory of 1850 included Nevada, western Colorado,
and a part of Wyoming. The original territory was reduced in size several
times and in 1868 the state assumed the present size and shape of the state.
Planning was of paramount importance to both Mormon leaders Joseph Smith
and Brigham Young. Their cities and towns were laid out in detail. Brigham
Young's Utah was probably the most planned region of its size in the America
of his day and perhaps of any day since. For the pioneers planning included
political, cultural, and economic activities as well as urban and regional
site planning. Their intent was to develop a strong center in the Salt Lake
Valley that could preside over a far-flung empire of settlements.
As a colonizer, Brigham Young believed that to claim land it had to be occupied.
He instructed teams of immigrants to settle the corridors that radiated
from the Salt Lake hub. Membership in a settlement team was sometimes a
church calling. Brigham Young personally selected the sites for many of
the settlements and then suggested how to lay out the communities. As a
planner and colonizer, Brigham Young presided over the establishment of
some 360 communities. History ranks him as one of the leading colonizers
of all time.
Soon after their arrival in the Salt Lake Valley, the pioneers colonized
the productive areas that surrounded the valley. This was largely the Wasatch
Front as far north as Brigham City along with a southern corridor to the
border of the territory. A few outlying settlements were also established
at an early date; they included Genoa (Mormon Station), close to Reno, Nevada,
in 1845; San Bernardino, California, in 1851; and Lemhi, Idaho, in 1855.
Following the death of Brigham Young, rural counties in Utah maintained
basically stable populations until after World War I. The state's population
was relatively small compared to that today and agriculture was much more
important to the economy then. From the 1920s to the early 1970s, however,
there was a general and pronounced migration to the Wasatch Front, particularly
to the Salt Lake Valley. During the 1970s, population losses ceased for
counties in Utah and the migration structure for the state changed from
one of losses to one of sharp gain. In fact, more people entered Utah from
1970 to 1980 than migrated to the state from 1847 to 1910.
As the decade of the 1980s began, the state continued to have net in-migration;
but this soon ceased and for several years, beginning about 1984, there
was a net out-migration. The state's population continued to increase, however,
because of a high natural increase rate. In the early 1990s the trend once
again reversed as Utah's healthy economy attracted more people to the state
than those who left.
Land Ownership. Federal ownership accounts for 67 percent of the land
in Utah, with another four percent included in Indian reservations. The
primary federal landlords are the Bureau of Land Management (BLM), the Forest
Service, the Department of Defense, and the National Park Service.
Private ownership claims 22 percent of the land, and the remaining seven
percent is owned by the state.
Agriculture. Much of the naturally best agricultural land in Utah
is along the Wasatch Front, but is not farmed. It is used for cities, suburbs,
factories, shopping centers, roads, and highways. Agriculture cannot compete
favorably with more lucrative land uses in this region.
Livestock dominates Utah agriculture because grazing is the best and sometimes
the only reasonable agricultural use for huge areas of the state due to
the climate, the landform, or both. Dry farming and growing fruit on benchlands
are other ways farmers have accommodated to the natural environment.
The most important of the market-oriented agricultural activities is the
dairy industry. There is some truck gardening to supply fresh produce to
the local markets, but it is much less significant today than it was in
the past. Turkey and mink growing are two prominent targets of opportunity
products, while cotton and sugar beets were of historical importance.
People. Utah has one of the nation's youngest populations, lowest deathrates,
and highest birthrates. In recent years, however, both the birth and the
fertility rates have declined sharply. Still, the state's natural increase
rate is among the highest in the nation and will probably continue to be
The percentage of people classified as minority by the Census Bureau is
low, at less than 10 percent being well below the national average. People
of Spanish origin comprise the largest of the census-enumerated minority
groups, and blacks comprise the smallest. More than half of the state's
population claim English ancestry, which is the highest of any state in
the nation. Scandinavian and German-rooted people are the next most numerous.
Settlement Patterns. A few statistics highlight Utah's settlement
patterns. In 1990 approximately 77 percent of the state's population resided
along the Wasatch Front on 4.3 percent of the land area. Close to 42 percent
of the state's inhabitants live in Salt Lake County on only 0.98 percent
of the land. This means that 95.7 percent of the land is away from the Wasatch
Front, but it holds only 23 percent of the people. Fifteen of the state's
twenty-nine counties have a population density of less than five people
per square mile, whereas the figure is close to 1,000 per square mile for
Salt Lake County. Away from the Wasatch Front settlement is in small cities
or towns. Residence on isolated farms or ranches is rare.
See: Atlas of Utah (1981); and A.L. Fisher, Geography of Utah
Albert L. Fisher