Wednesday, November 17, 2021

It Is Time To Decommission Lake Powell and Glen Canyon Dam - 2015

 


Cold, sterile water emanating from Lake Powell and Glen Canyon Dam supports green fronded algae and not much more  - Click for larger image (http://jamesmcgillis.com)

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 -

During his expedition of 1869, John Wesley Powell and his crew traveled the length of the Grand Canyon, taking scientific measurements as they progressed - Click for larger image (http://jamesmcgillis.com)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 By the early 1960s, the building of the Glen Canyon Dam along the Colorado River in Arizona was a 24-hour per day operation - Click for larger image (http://jamesmcgillis.com)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.

In this 1965 photo, as in 2015, Lake Powell was at approximately one half capacity - Click for larger image (http://jamesmcgillis.com)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.

This late 1960's photo of Lake Mead shows no sign of the the "bathtub ring" of exposed minerals that we see there today - Click for larger image (http://jamesmcgillis.com)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.

This diagram of various water intakes at Glen Canyon Dam, also depicts the "dead pool", from which no further water can exit the dam - Click for larger image (http://jamesmcgillis.com)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
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Since 2006, when this picture was taken, the water level of Lake Powell has continued to recede - Click for larger image (http://jamesmcgillis.com)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, This Bureau of Reclamation promotional piece from the mid-1960s shows the proposed Colorado River dams at both Marble Canyon and Bridge Canyon - Click for larger image (https://jamesmcgillis.com)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 In this view of the front of Glen Canyon Dam, a patch of green in the lower-right indicates that seepage has worked around the dam and is exiting the canyon walls through a horizontal fissure or fault in the soft sandstone - Click for larger image (https://jamesmcgillis.com)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.

In the lower basin of Lake Powell, various benches that indicate previous high-water marks are clearly visible far above the current shoreline - Click for larger image (http://jamesmcgillis.com)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 This 2014 view of Lake Powell from Wahweap Overlook shows the dry land of Antelope Island, where only two decades ago, water covered that whole area - Click for larger image (http://jamesmcgillis.com)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 During a 1965 visit to Lake Powell, the author encountered the crystal clear air of the desert, unlike the current coal-fired haze that shrouds much of the Four Corners region - Click for larger image (http://jamesmcgillis.com)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 As viewed from Wahweap Overlook, Glen Canyon Dam appears to hold back earth, not water, as one day it may - Click for larger image (http://jamesmcgillis.com)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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