It Is Time To Decommission Lake Powell and Glen Canyon Dam
The Lower Colorado River Basin -
The Lower Colorado River Basin
begins at the cold, sterile outfall of Glen Canyon Dam. From that
point on, the river again receives sediment from various streams and
seasonal watercourses. Tributaries such as the Little Colorado River and Kanab Creek
join the river, but provide only a fraction of the sediment that
enters Lake Powell. Lake Powell loses as much as 5.6% of its volume
annually to a combination of evaporation and seepage into its sandstone basin. As a result, the toxic load of chemicals, fertilizer
and heavy metals from upstream is concentrated in the Lower Colorado
River. Recently, the U.S. Geological Survey identified raised levels of
both selenium and mercury in the Grand Canyon watershed.
Grand Canyon Country -
After the Civil War, officer and veteran John Wesley Powell explored the length of the Grand Canyon. Attempts to protect the Grand Canyon
began early in the twentieth century. In 1906, President Theodore
Roosevelt first declared a game preserve there and in 1908, he used the Antiquities Act of 1906
to create Grand Canyon National Monument. In 1919, three years after
the creation of the National Park Service, congress created Grand
Canyon National Park. In 1975, the former Marble Canyon National
Monument, which followed the Colorado River northeast from the Grand
Canyon to Lee's Ferry, became part of Grand Canyon National Park. In
1956, the U.S. Bureau of Reclamation (USBR) began building of Glen
Canyon Dam. Until that time, “more dams in more places” on the Colorado
River was the rallying cry of federal land managers.
In the early 1960s, the USBR touted plans for Marble Dam in Marble Canyon, downstream from the Glen Canyon Dam and Bridge Canyon Dam
downstream from the Grand Canyon itself. Slowly, the populace and land
managers alike realized that the Colorado River could not support so
many storage facilities along its watercourse. Even with optimistic
flow projections, the collection of proposed
dams would never be full, let alone half-full. After the victorious
building Glen Canyon Dam, promoters of federal dam projects along the
Colorado River had to look elsewhere for places to build their
socialist make-work projects.
The original rationale for building Glen Canyon Dam was to help regulate
periodic flooding within the Lower Colorado River Basin. In that
regard, Glen Canyon Dam became a classic case of “overkill”. Not only
did the dam regulate water flow in an unnatural manner, it also
sterilized whatever remaining water flowed through both Marble and
Grand Canyons. There were no spring floods to rearrange and propel
various sediments downstream. Without periodic recharging of sediments,
beaches and shoals disappeared from the watercourse. Without new
sediments to impede flow, the river scoured away the remaining
sediments, including rocks and boulders of immense size. In the end, it
was as if a slow motion flood had taken the life out of the river.
Only
dissolved solids, such as salts and heavy metals could make it through
the sieve that is the mudflats of upper Lake Powell. In recent years,
regulatory authorities at Glen Canyon Dam have allowed several simulated floods
to recharge the beaches and hollows necessary for a more diverse
ecosystem in Marble and Grand Canyons. Even so, most of the sediments
required to sustain life downstream remain trapped in the methane volcano-fields
at the upper reaches of Lake Powell. If one were to plan today for the
least healthy Lower Colorado River possible, Glen Canyon Dam would be
an essential aspect of that plan.
Lake Mead -
Currently, Lake Mead covers approximately 247 square miles, while Lake
Powell covers a slightly larger 254 square miles. At Hoover Dam, the
surrounding geology includes “K-T Volcanics”, which are mostly
"Cretaceous and Tertiary andesitic and basaltic flows". In other words,
both Hoover Dam and Lake Mead rest on old, hard rock. Glen Canyon Dam
resides in and Lake Powell rest upon younger, softer and more permeable
sandstone. Once water reaches Lake Mead, a bit less than one percent of
it evaporates annually.
Comparing Lake Powell and Lake Mead.
The
generally accepted figure for annual evaporation at Lake Powell is
about three percent. Because of its porous, sandstone shell, Lake
Powell loses an additional 2.6% of inflow to seepage. The dry sandstone
under and around Lake Powell is like an insatiable sponge, constantly
drawing water away from the reservoir. If we compare the .09%
evaporation loss and negligible seepage at Lake Mead to the 5.6% total
evaporation and seepage at Lake Powell,
we find that Lake Mead is 6.2 times more efficient at preventing
environmental loss of volume. In the old days, one might call that a
differential calculus or maybe even a quantum leap.
If
the main goal is to preserve and conserve water in both the Upper and
Lower Colorado Basins, Lake Mead is the best place to do that. If Lake
Mead were at full capacity, it would grow from the present surface area
of 247 square miles to a total of 255 square miles, or a positive
change of 3.2%. In both lakes, evaporation is largely dependent on
surface area and insolation. By reducing Lake Powell to “dead pool”
size and increasing Lake Mead to near full capacity, water losses due
to both evaporation and seepage along the Colorado River would decrease
dramatically.
The Navajo Nation -
As a political and cultural entity, the Navajo Nation has had a long and difficult relationship with coal. To this day, many Navajo homes burn coal for both cooking and heat. At Black Mesa, near Kayenta,
Arizona, large-scale mining destroyed the underlying aquifer and left a
moonscape of physical destruction on the surface. In recent decades,
aging coal-fired facilities such as the Four Corners Generating Plant,
west of Farmington, New Mexico and Navajo Generating Station
(NGS), near Page, Arizona came under increased scrutiny. As a result,
the Navajo Nation doubled down on coal by completing various ownership
and responsibility agreements designed to keep the coal fires burning.
Ignoring the health and welfare consequences of an old energy, coal economy, the
Navajo Nation sought to justify its new status as a gross polluter of
the environment. To do this, they invoked the sanctity and necessity of
jobs in the mining,
transportation and production of coal-fired energy. In sad
consanguinity with Navajo/corporate mining deals of the past, the
Navajo Nation has accepted ill health and decreased life expectancy for
its people. In exchange for a minimal number of old energy jobs, the
Navajo Nation continues to degraded the environment of All that Is.
The Correct Course of Action -
There are advocates for keeping Lake Powell half-full and Lake Mead
half-full. In their justifications, they point to Lake Powell tourism,
payment of long-term indebtedness,
loss of power production and water delivery to Page Arizona and NGS as
primary reasons for maintaining the status quo. They pass off the higher
seepage and evaporation rates at Lake Powell by saying, “Water
evaporates – get over it”.
Scientific studies of evaporation and other storage losses are now under
peer review. Preliminary findings indicate that emptying Lake Powell
to dead pool size and transferring its contents downstream to Lake Mead
could save up to one million acre-feet of water annually. To put that
into perspective, the City of Los Angeles consumes about one million
acre-feet of water annually. That amounts to almost one fourth of
California's annual allotment of Colorado River water.
Lake
Powell has become a beautiful anachronism in the desert. It is an oasis
built over a sinkhole, and has failed as an efficient water storage
scenario. On the strength of water conservation alone, the U.S. Bureau
of Reclamation should decommission Lake Powell. For a transitional
period, both NGS and the City of Page,
Arizona could continue to draw water as Lake Powell reduces toward
dead pool size. Over time, Page would likely shrink economically nearer
to what it was before exuberant boosters and developers began
publicizing luxury houseboats and “lake view estates”. Once again,
river runners and rafters will develop new businesses based in Page.
Once we scientifically determine that the Navajo Generating Station is a climate
change engine, responsible parties will find alternative, more
progressive energy sources for air-conditioning or to pump water around
the West. New energy
technologies will arise to pump Colorado River water over several
mountain ranges during its trip to to Phoenix and Tucson, Arizona. If
Arizona residents and politicians reject new technologies and logical
courses of action, they will be the first and hardest hit of all
Colorado River stakeholders. In 2015, only an exceptional monsoon
season allowed Arizona relief from mandatory reductions in water
withdrawals from the Colorado River .
If the people of Arizona support the recombination of two dying
reservoirs into a single healthy one, they may avoid future mandatory
cutbacks and major scale water rationing. By installing solar and wind
power near the pumps along the Central Arizona Project, Arizona could
reduce or eliminate its reliance on NGS
and dirty coal. Phasing out NGS over a period of ten years should
allow sufficient time for installation of new and renewable energy
sources for vital water pumping functions. Federal incentives and
business development investment in Navajoland should offset any jobs
now held by Black Mesa black-lung miners and the stokers of the coal
fires at NGS.
Some people say that human activities have no net effect on our world,
our environment or our prospects for a sustainable future. Others
believe that human activities, especially the burning of fossil fuels
are the root cause of Climate Change,
Global Warming and the looming Sixth Extinction. If that Sixth
Extinction comes to pass, will we be mere observers or its final living
participants? Sixty-five million years hence, some intelligent species
may come to Earth and study the last remaining fossils of humankind.
After visiting the petrified mudflats that once were the upper reaches of Lake Powell, imagine the
scientific conclusions of those future visitors; “They could have
saved themselves, but did not care enough about Nature to do so”.
The Benefits of Correct Action -
I almost forgot to mention, if we decommission Glen Canyon Dam, the real and original Glen Canyon of the Colorado would reappear. If so, we can all watch as Mother Nature repairs that Eden in the Desert to its previous glory. If still living, both John Wesley Powell and Edward Abbey would approve.
This is Part 3 of a three-part article. To begin at Part 1, please click HERE. To return to Part 2, please click HERE.
By James McGillis at 12:01 AM | Colorado River | Comments (0) | Link
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