City Creek Nature Notes – Salt Lake City

January 17, 2017

January 17th

Filed under: Duck, Flood retention pond, Mountain Chickadee, picnic site 7, Weather — canopus56 @ 9:34 pm

Ice Mirror

1:00 p.m. City air grows thicker; buildings a mile away are reduced to mere outlines; and, during these inversion layers, the eyes burn and breathing becomes more labored. I escape to the canyon. I will not be able to reach clean air, but at least will see the beginning of blue skies. It is growing warmer, and the two ducks at the flood retention pond, who have used the pond as a refugee during this coldest part of the year, have left. There is only one chickadee call near the canyon’s mouth.

The retention pond has melted and then partially re-frozen. The frozen shaded part is covered with a thin layer of glass ice. Like its arctic ice pack counterpart, the floating ice layer has fractured and a network of miniature pressure ridges have formed in its surface. When sunlight hits it a the right angle, the glass surface reflects blue-green colors highlight by a bright fire-yellow spider web of pressure ridges. The pond at picnic site 5 is free of ice, and one small trout – the first that I have seen in the lower canyon stream since November 25th – dashes into the shadows. Above milepost 1.0 between picnic site 7 and picnic site 8 where the stream froze completely over into a milky cathedral (Dec. 20th), now there is a open channel in the middle of the stream, but near the banks, the stream retains its original thick layer of ice. In spots in this stretch, the stream has re-frozen and it is covered by a thin layer of delicate window-pane glass ice. This re-freezing process is echoed in the snow on the sides of the road: the surface has melted and then re-frozen. This is “crust” snow – a bane to both back-country and developed area skiers. Placing a foot on the surface, it feels strong, but when any weight is put on it, ones foot breaks through the surface revealing a sugar-powder snow underneath. At a winter intermittent seep near picnic site 7 where warmer water melts overlaying snow, rising vapor from the seep encrusts a cinquefoil sprout and overhanging twigs with its re-frozen waters in the form of intricate ice rime crystals.

In Thoreau’s “Journal” on January 17th, 1852, he notes a sign of a clear, rested mind: enjoying watching sunsets. He comments on the infinite variety of shapes created by clouds.

On January 17th, 1918, Waterworks C.F. Barrett warned of flooding from City Creek into the city because of abnormally high snowfall (Salt Lake Telegram). On January 17th, 1909, City Water Commissioner Frank M. Matthews reported that City Creek delivered approximately 11,000,000 gallons of water a day to the City and that improvement of the road using prison labor continues (Intermountain Republican).

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January 3, 2017

January 2nd

Filed under: Duck, Flood retention pond, Geology, People — canopus56 @ 5:39 pm

A Bend in the Road

5:30 p.m. At the flood retention pond, the two ducks are asleep while floating. They are completely motionless and have turned their necks to lay their heads on their backs. As I start up the canyon, eight hunters are loading into their cars, and the watershed patrol person is bringing another four out in the back of the city truck. None have a taken an elk. There are only three or four persons on road and shortly, I am alone at milepost 1.5 enjoying the quiet depths of winter in the fading light. I am looking down at the mouth of Pleasant Valley, and about a quarter-mile below it, canyon bends and turns about forty-five degrees in a southeasterly direction.

Gravity pulls water straight downhill, and for many of the canyons of the Wasatch Front Mountain Range, canyons erode in almost straight lines from the ridgelines to the valley floor. If there is a bend in a canyon’s descent, this may signify a hidden geologic fault line. Examples include Elbow Fork in nearby Millcreek Canyon and Storm Mountain in Big Cottonwood Canyon. At the red bridge below milepost 1.0, City Creek Canyon bends twenty-two degrees around a curve from a north-east direction to a north east-easterly direction and then opens into Pleasant Valley.

Van Horn and Crittenden’s 1987 geologic map of the area explains why the bend in City Creek occurs. The Pleasant Valley fault line runs due north-south through milepost 1.0 and the north-west massif where the canyon opens into Pleasant Valley. One can see the effect of the fault at red bridge and mile 0.9. The sandstone layers on the south and north canyon walls are horizontal, but at Chimney Rock above the red bridge (Dec. 24th), the layer has been rotated to a 90 degree vertical angle. The Pleasant Valley Fault continues along the south-east side of the creek, but on the west side at mile 0.5, sandstone conglomerate Shark Fin Rock (Nov. 23rd) is similarly rotated to the vertical.

The fault continues down-canyon, exits and then turns east at the foothills, and there it dissipates. But a quarter mile south, at the Morris Reservoir tanks, another fault that is hidden below the surface – the City Cemetery Fault – begins. It continues traveling east along the 11th Avenue bench; and, then the fault turns due north, becomes visible at the surface, and meets Little Twin Peaks on the Avenues ridgeline. There the City Cemetery Fault turns due east and runs between the two peaks. The Cemetery Fault is why the two peaks are there. Each peak sits on the other side of the fault. Next, the fault runs south for a few hundred feet before it ends, and this marks the north east corner of the city with giant geologic question mark. The Pleasant Valley fault is not active, but it is why City Creek stream makes the shape of a boot, and geologically speaking, it kicks the City in its proverbial northeast end.

In Thoreau’s “Journal” on January 2nd, 1854, he notes pink light falling on snow and a blue light in the shadows of snow. January 2nd, 1854, he notes that the colors of winter sunsets are enhanced by ice crystals in the atmosphere. On January 2nd, 1853, he describes the beauty of the oak forest covered with a heavy snow and with ice. On January 2, 1841, he describes a fox traversing a snow covered pond.

On January 2nd, 1937, the Salt Lake Telegram reported that the Utah Audubon Society will at its monthly meeting, the results of its Christmas bird count, and that later in the month, Society will have a field trip up City Creek Canyon. On January 2nd, 1916, the Salt Lake Tribune reported on progress towards projects built using proceeds of a 1914 bond issue to deliver enough water to the City to support 600,000 people. Those projects include the Lake Mary and Lake Phoebe dams in Big Cottonwood Canyon and a 5,000,000 gallon distribution reservoir at Pleasant Valley in City Creek Canyon. On January 2nd, 1910, the City reported that it receives 10,000,000 gallons of drinking water from City Creek Canyon.

September 21, 2016

September 10th

Filed under: Birds, Cattails, Crow, Duck, Gambel's Oak, Light, Plants — canopus56 @ 1:11 am

Cattail Refuge

Noon. The canyon is closed today until 5 p.m. The City is finishing cleaning out two flood retention ponds at mile 3.1. The ponds were full of thickets of cattails. These trap sediments and purified the water. In past years, I’ve seen both geese and ducks resting in the ponds during their spring migration. This spring one duck remained and raised a small brood for about 2 months. A bulldozer has scrapped the ponds clean to mathematical precision. The cattail thickets are piled in a heap at one end. Trucks are coming to remove the debris. The cattails should reestablish themselves in a couple of years and the ponds will again become a refuge for birds.

I get a head start on the official reopening of the canyon at 5 p.m. by jogging up the pipeline trail, and I am rewarded by having the canyon to myself, except for one other regular runner, a nurse-mathematican. At mile 1.8, a single crow, sits on top of a telephone pole squawking loudly. The jog out is in solitude and through warm sunlight that is dappled by the overhanging Gambel oaks.

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