The Historical Saga of Glen Canyon Dam and Wahweap Bay
Any visit to Glen Canyon Dam and Lake Powell
is a memorable event. The surreal nature of a giant concrete plug
embedded in soft Arizona sandstone, while holding back the second
largest reservoir in America is a site to behold. Visitors can walk
across the bridge that spans the 800-foot chasm just downstream of the
dam. As large trucks rumble across the bridge at well over the
twenty-five mile per hour speed limit, the whole structure resonates at
a low pitch. Many of the smaller vehicles flagrantly violate the speed
limit. There are no automated “Slow Down” signs and little actual
enforcement of the speed limit.
On a recent visit, I trained my camera lens between the chain links that
make up the safety fencing along the bridge. Looking down at the dam,
which registers 710-foot tall, I noticed a strange anomaly. Where the
canyon wall abuts the lower-right portion of the dam, steel rods and
plates had been installed to keep the sandstone from crumbling. To make
the scene even more startling, water had seeped from behind the dam
and along a horizontal seam. 
The
result was a large, horizontal mosey patch leading downstream from the
dam itself. Apparently, the dam was weeping around its eastern edge,
and engineers had installed protective bolts and plates. Their intent
was to keep the lower canyon wall from crumbling away and exposing more
of the concrete dam.
If you have ever observed a concrete patch on an asphalt road or an
asphalt patch on a concrete road, you know that the hard concrete and
the softer asphalt to not make for a happy marriage. Concrete and
asphalt expand and contract deferentially under pressure, heat or
moisture. The result is that sooner or later the two will separate and
create a greater problem than before the patch was made. Likewise, the
4,901,000 cubic yards of ever-hardening concrete within Glen Canyon Dam are embedded in the soft and porous sandstone of Glen Canyon itself.
When
fully stressed by an overfilled condition in 1983, Lake Powell
contained over 27-million acre-feet of water. To avoid spilling water
over the front of the dam and possibly losing it all together, water
managers were forced to run both spillway tunnels at their designed
maximum of 208,000 cubic feet per second. Anonymous sources later
revealed that as the extended water release activity continued, the
entire dam resonated and thrummed. Since parts of the twin spillway
tunnels were bored through sandstone, huge chunks of that natural
formation broke loose and swept out into the Colorado River.
How much lasting damage was done during the 1983 water release event
will never be known. Large public agencies like the United States
Bureau of Reclamation (USBR),
which runs Glen Canyon Dam, have a habit of hiding as much
controversial information as they can. What they cannot hide is the 
thermal
stress on the dam. In January the average high temperature at nearby
Page, Arizona is 44F degrees. In July, the average high temperature is
97F degrees, or 57F degrees higher.
Daily temperature cycles should also be considered. Each day throughout
the year, the high and low air temperatures vary by up to 24F degrees.
Although the concrete in the dam does not thermally cycle as
dramatically, the face of the dam is shaped like a parabola thus
concentrating the sun on its southeastern exposure. With cold water
behind the dam and hot sun shining on the front of it, how does the dam
dissipate that energy into the sedimentary rock in which it stands?
Maybe that differential stress is why the unmentioned grout, steel bolts
and plates have been installed in the sandstone canyon wall along the 
lower right face of the dam.
After traveling over the Glen Canyon Dam Bridge, I proceeded west on
Highway 89 to the Wahweap Overlook turnoff. The directional signage
from Highway 89 West is minimal, so the obscure turnoff is easy to
miss. The paved road up the hill to the overlook is adequate, but the
unpaved parking area at the top has no traffic markings or designated
parking spots. Since the inception of the dam, the Wahweap Overlook
has defined how an “overlooked” overlook might look. Given the
popularity of the site and its status as a senior citizen, authorities
should have paved the parking area and installed a restroom facility
sixty years ago. Perhaps it is a moot point, since the drying of Lake
Powell could soon leave Wahweap Overlook as just another dry knoll in
the Arizona desert.
In
May 2021, from Wahweap Overlook I could still see Wahweap Marina on the
near shore of Wahweap Bay. In the middle distance lay Castle Rock,
which looks as much like a castle as any other “Castle Rock” in the
Western U.S. Farther north and east stands the eroded volcanic shape of
Navajo Mountain (elevation 10,387’). With some effort and a short hike
down the hill, I could look downstream and see the top portion of Glen
Canyon Dam. Ironically, the water level was about the same as I
remembered it from my first visit to Lake Powell in 1965. Keep in mind
that Lake Powell was then still receiving its initial fill of once
abundant Colorado River water.
Even with its steadily shrinking size, Wahweap Bay still looks grand,
giving Lake Powell a spacious, breathtaking feel. Most visitors do not
realize that prior to the construction of the dam, the flow of the
Colorado River never touched 
what
we now call Wahweap Bay. The main canyon, known as Glen Canyon,
meanders northeast from the dam in a rocky trench. The containment
created by that sheer cliff does not broaden out again for many miles.
From the Wahweap Overlook, I could see neither Glen Canyon or the Castle
Rock Cut, which once was Lake Powell’s much shorter version of the
Suez Canal. As such, it was a manmade cut in the sandstone, which
allowed boats to pass from Wahweap Bay upstream to Warm Creek Bay.
Transiting that trench by boat bypassed a stretch of Glen Canyon,
shortening the distance from Wahweap to the upper reaches of Lake
Powell by twelve miles, or over one hour of travel time.
First
cut into the sandstone in the 1970s, and with its bottom deepened to
3,600’ elevation in 2014, the Castle Rock Cut served boaters for
decades. As of 2021, Google Maps
still shows the cut as if it is operational. I suppose the map keepers
at Google Maps are either too lazy to show current reality or perhaps
they believe that the lake will refill itself and reactivate the cut for
boat travel. An environmental assessment in 2008 had optimistically
stated that the cut could be deepened to 3,580’ elevation. On July 23,
2021, the reservoir’s level fell to 3,555’ elevation, or twenty-five
vertical feet below the final proposed depth of the Castle Rock Cut. In
other words, the Castle Rock Cut now stands high and dry.
The iconic scene of Charlton Heston finding a destroyed Statue of
Liberty in the 1968 original Planet of the Apes movie was filmed on the
beach at Paradise 
Cove,
California. However, the opening scene, which depicts his prior crash
landing in a spacecraft was filmed at Lake Powell. With such Science
fiction credibility already established at Lake Powell, I suggest that
the “Sandcrawler”,
a fictional transport vehicle in the Star Wars universe that is found
on the desert planet Tatooine be redeployed to the Castle Rock Cut.
There it could be utilized as a houseboat transporter. It could scoop up
a boat from Wahweap Bay, and then use its many treads to crawl the
Castle Rock Cut to Warm Creek Bay. There, it could disgorge the
houseboat and its happy passengers, all in a matter of minutes.
Back
in the reality of the twenty-first century, the Castle Rock Cut joined
the Bullfrog Main Launch Ramp, Antelope Point Public Launch Ramp, Hite
Launch Ramp and Stateline Launch Ramp on the list of closed Lake Powell
boating facilities. As of this writing, the main launch ramp at
Wahweap Marina had an expected closure date of mid-August 2021.
Recently, the National Park Service (NPS) began preparing a smaller,
“Auxiliary Ramp” not used since the 1960s. It will be able to launch or
retrieve only two boats at a time. The NPS was also preparing the
Stateline Auxiliary Launch Ramp for limited use later this year.
Neither auxiliary ramp will accommodate houseboats over thirty-six feet
in length.
Thinking back to the original Planet of the Apes movie,
I imagined an event thousands of years from now. An errant spaceship,
piloted by a descendant of Elon Musk might aim his disabled spacecraft
for the dead pool of Lake Powell. Assuming a successful water landing,
the survivors might hike out in the direction of what once was Wahweap
Bay. There, Elon the 125th and his crew might come across the huge
concrete ramp at Wahweap. With Lake Powell no longer reaching Wahweap
Bay, the long concrete ramp at the former Wahweap Marina would be as
mysterious as the Pyramids at Giza. The survivors might ask, “What type
of spacecraft could have launched from this dry and desolate ramp?”
Throughout my own lifetime, the Glen Canyon Dam and Lake Powell have represented subterfuge,
boom and bust. As I reflected on that, I knew it was time to go.
Fifty-six years after my first visit to Wahweap in 1965, I wondered if
this would be my last. Having photographically documented the Wahweap 
Overlook
view for the past fifteen years, I snapped a few more pictures and
then departed. What my photos revealed was the continued desiccation of
Lake Powell. In the past six years alone, a large section of Wahweap
Bay had gone dry.
Finished in the early 1960s, Wahweap’s concrete launch ramp extended
farther and deeper into the lake than any other launch ramp. At the
time no one imagined that the surface of Lake Powell
would ever fall below the end of the concrete ramp. As I drove away,
the question in my mind was, “Once it is reduced to a shadow of its
former glory, will Wahweap Marina ever again thrive as a pleasure
boating facility?” I have my doubts.
This concludes Part Four of a Five-Part Article. To read Part Five, click HERE. To return to Part One, click HERE.
By James McGillis at 04:29 PM | Colorado River | Comments (0) | Link
