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1960
1998
2007
Side by side comparison
Map
ARCH CANYON 2
General Description: This photo-point is on the south rim of Arch Canyon
approximately one half mile upstream from it mouth. The view is northeast across
Arch Canyon and Comb Wash.
Legal Description: NE1/4NE1/4 Section 26 T.37S., R.20E.
COMPARISON: Vegetation density and diversity has increased along the Arch
Canyon stream channel in the 35 to 38 years between the two photographs.
Riparian plant species now present include Fremont cottonwood, coyote willow,
yellow willow, bulrush, common reed, cattail, Baltic rush and a few tamarisk
plants. The stream channel is now much more narrow, is developing sinuosity and
is properly functioning.
A significant difference in vegetation and stream channel characteristics on the
main stem of Comb Wash is visible in the mid-portion of the photographs. The
channel is much more narrow and is supporting a more dense vegetation cover.
Original:
Date: ca. 1960 (- A)
Photographer: Parker Hamilton
Source: Utah State Historical Society
Photograph Number: USHS No. 17387 |
1998 Retake:
Date: July 15, 1998 (- B)
Photographer: Earl Hindley
Source: Bureau of Land Management, Salt Lake City, Utah |
2007 Data
2007 Retake:
Date: April 26, 2007
Photographer: Earl Hindley
Source: Earl Hindley
General
Description:
The photo-site is on a rocky ledge on the south side of Arch Canyon
approximately one half mile from its mouth.
Location:
N. 37 32.652’ W. 109
40.469’ (Lat./Long.)
Comments/Comparison: High water flow in 2006 deposited significant
amounts of sandy soil as well as cutting several new overflow channels in the
entire visible flood plain across the bottom of the 2007 photograph (note
accompanying photos A, B and C which were taken in the canyon just left of view
area). The main channel was rerouted from the south to the north in an area near
the alcove. This stream reach has developed a significant riparian community
since the ca. 1960 photograph was taken. The development is apparent when the
1960 photograph is compared with the 1998 photograph. This development has
continued from 1998 where the willow community is maturing and expanding
laterally. The common reed (Phragmites), rush, cattail community had expanded
significantly to the south by 2007. Riparian
vegetation including willows, cottonwoods, common reed, cattail and rushes have
become firmly established here which in turn created a distinct flood plain and
narrowing of the channel by capturing sediments from previous water flows. This
narrower channel (see accompanying photograph D) cannot accommodate the high
water flow which this drainage is capable of producing and contributed to over
bank flooding of 2006. (Feb. 2007)
The April 2007 photographs clearly show where Arch Creek’s main channel has been
rerouted from south to north since the earlier photographs were taken from this
location. However, water still flows in the earlier (southern channel).
The accompanying photographs A, B, C and D. all illustrate
the emergence of new riparian plant specie growth since the floods of 2006.
(April 2007) | |
Angel Arch, Canyonlands National Park,
San Juan County, Utah
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