The Basemap Area
"The
Colorado grows grapes in New Mexico, brews beer in Colorado, raises
minnows in Utah, floats rafts in Arizona, lights jackpots in Nevada,
nurses elk in Wyoming, freezes ice for California, sweetens cantaloupes
in Mexico" (Carrier, 1991). The Colorado River begins at elevations
of 14,000 ft. on the continental spine of the Rockies near Mammoth
Glacier in Rocky Mountain National Park and in Wyoming's Wind River
Range where the Green River feeds into the Colorado. The Colorado
has the greatest elevational drop in North America and carves the
mile-deep Grand Canyon. Only the seventh longest in the U.S., it
runs for 1,450 miles, but the volume (15 maf./yr.) is only a fraction
of that of the Columbia (92-maf/yr.) or Mississippi (400 maf/yr.).
It is also the most silty (380,000 tons/day are moved downstream)
and one of the saltiest (carrying 9 million tons a year) (World
River Review, 1997). Federally-owned, it as been nearly regulated
out of existence: the river has scores of reservoirs, diversion
dams and pumping stations, hundreds of miles of aquedects and tunnels,
thousands of miles of canals, and 30 hydroelectric plants (Bureau
of Reclamation, 1999).
Near Yuma, on the border of Arizona and Mexico,
the Colorado River backs up behind Imperial Dam, which takes more
than 20% of the water, the single largest chunk of the river, and
flows through the All American Canal about 80 miles west of California's
Imperial Valley (BoR, 1999). The Valley receives only three inches
a year in rainfall (NOAA, 1996); hence, the valley's 500-million
acres of farmland would revert to desert without the 2.9 million
acre-ft. of water drawn from the Canal (Pontius, 1997; Bureau of
Reclamation, 1999). The Canal crosses the Imperial Sand Dunes and
15% (70,000 acre-ft./yr.) soaks into the sand, while another 1 maf.
of water runs off and beneath the Valley's irrigated, productive
fields (Pontius, 1997; Bureau of Reclamation, 1999). Altogether,
700 prosperous farmers generate about a billion dollars a year in
produce, grain, and livestock; and they have a senior right to the
river's water (Pontius, 1997). However, the land is so salty and
the river water is so saline due to being extracted, evaporated
from the reservoirs, passed over the natural salt beds, and poured
through soil that was once the bottom of an ancient sea, it takes
extra water, poured through the soil, to flush salt away from roots
(Carrier, 1991). Pipes buried 1-5 meters feet deep carry the excess
salty water away through 1,400 miles of pipeline carrying drainage
to rivers that empty into the briny Salton Sea (Glenn et al., 1996).
More efficient irrigation methods, like the drip system, are replacing
these older methods of irrigation.
Based on Bureau of Reclamation statistics, Carrier
(1991) describes the following: The California cities that receive
33% of their municipal water from a 242 mile Colorado River Aquaduct
receive a billion gallons of water/day. The Arizona aqueduct system,
umbilical cord amongst the Saguaro cacti, slows the depletion of
groundwater pumped from deep wells. The Bureau of Reclamation spent
$3.5 billion on the aqueduct network, which includes the Central
Arizona Project (CAP) that stretches 335 miles from Lake Havasu
to central Arizona farms, Indian reservations, industries and cities,
ending in Tucson (taking 1.5 maf./yr.). A pump house at CAP draws
1 billion gallons/day of water for southern California and carries
water for ten tribes of Native Americans. It is not covered and
not protected from evaporation; comparably, the evaporation rate
off Lake Powell is such that the lake decreases by 5 feet annually.
Not
counting evaporation losses, nearly a half-trillion gallons of water
a year is drawn from the river, so cartographers no longer draw
the Colorado River as a vibrant blue line. Furthermore, the Bureau
of Reclamation helped build a coal plant near Page, Arizona so farmers
can subsidize economically, which taints the air over the Grand
Canyon and the Navajo Reservation (Carrier, 1991).
The last of the Colorado River is pushed into Canal Central below
Morelos Dam in Mexico, south of Yuma, and the riverbed becomes shallow
enough to wade across. There are 15,000 or so farmers living in
the delta area and they only farm 80% of their land because only
66% is irrigable (Sonora, Mexico) (INEGI, 2000a,b). The rest of
the water is for industrial or urban use, which is needed for cities
like Tijuana, Mexicali, and San Luis Rio Colorado. At least they
have profits to off set the cost of buying water (Calbreath, 1998
in Garcia-Hernandez, 2001). In 1997, Tijuana increased employment
by 14% seven times faster than in San Diego, California, due to
offshore manufacturing plants (the maquiladora industry). On the
U.S. side, agriculture draws 80-90% of the Colorado River's water
(in Mexico, agriculture is the primary consumer of water). Just
as the economic struggle in the U.S. is between the irrigators and
power interests, in Mexico, other Mexican industries (municipalities
and factories) are fighting for their share (Coronado, 1999).
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