Field Observations
Field Observations
Embedded Files
100m Reach 1km Upstream of Trapper Park
100m Reach 1km Upstream of Trapper Park
Deep and wide channel, low water levels showed an incision of ~2 feet. Access to floodplain is restricted by cars placed in bank. Within channel there were lots of changes in hydrology, small eddies produced by structure as well as coves and point bars were present throughout most of the reach. This energy dispersion is presented mainly by FNT's, there are small riffles throughout but very disconnected. Roughly 45% canopy cover that has fallen into the river in the past - thanks crack willow - no large phrag stands or tamarisks. Ironically there was a lot of trash caught in strainers, a dog that lost its tennis ball had a very bad day. Roughly in stage 5 of degradation, there is connection to a larger floodplain but it is burrowing quicker than it can flood. Slight meanders throughout reach, enough where it moves a fair amount of sediment and deposits decently sized point bars.
Deep and wide channel, low water levels showed an incision of ~2 feet. Access to floodplain is restricted by cars placed in bank. Within channel there were lots of changes in hydrology, small eddies produced by structure as well as coves and point bars were present throughout most of the reach. This energy dispersion is presented mainly by FNT's, there are small riffles throughout but very disconnected. Roughly 45% canopy cover that has fallen into the river in the past - thanks crack willow - no large phrag stands or tamarisks. Ironically there was a lot of trash caught in strainers, a dog that lost its tennis ball had a very bad day. Roughly in stage 5 of degradation, there is connection to a larger floodplain but it is burrowing quicker than it can flood. Slight meanders throughout reach, enough where it moves a fair amount of sediment and deposits decently sized point bars.
Logan River
The Logan River in Cache valley has a catchment area of 646 sq. km. The mainstem is 86 km long.
Map of USA and Logan UT Location
Map of USA and Logan UT Location
Source: Drivetofive
This figure depicts the watershed boundary of the Logan River and the mainstem is highlighted in blue.
Source: Google Earth Pro.
Figure: Elevational Profile of the Logan River. Source: Google Earth Pro.
The Logan river has a steeper slope in the headwaters and flat where it dumps in to cutler reservoir. Base-level control for the Logan is 1344m above sea level. The concavity (2A/H) is 0.612. A is the difference in elevation at the midpoint and the elevation at a straight line. The elevation at the midpoint is 1561m and the straight line is 1904m, A = 343. H is calculated by total relief of the river 2465m - 1344m = 1121m. 18,000 years ago the valley was apart of Lake Bonneville, this acted as a base-level control at 1554m above sea level. There are three dams on the Logan, these act as knickpoints.
Catchment Morphometrics
The watershed has an area of 646 km² (646,000,000 m²), with a perimetric boundary of 172 km (172,000 m). The catchment length is 92,000 meters.
Circularity Ratio A/Ac : The watershed demonstrates an Ac of 0.27, indicating a substantially elongated configuration.
Elongation Ratio A^0.5 / L: With a ratio of 0.27, the watershed presents an elongated morphometry. This metric implies a non-compact drainage basin configuration.
Form Factor Rf = A/L^2 : The calculated Rf of 0.076.
Elevation Characteristics: The watershed exhibits a substantial vertical relief of 1121m, with elevations ranging from 1344m to 2465m.
Relief Ratio (Rr) = Catchment Relief / Catchment Length : The Rr of 0.012 quantifies the watershed's vertical dissection, suggesting a moderately steep terrain with significant potential for fluvial erosional processes and sediment mobilization.
Drainage Characteristics Stream Length/ Watershed Area : The total stream length is 810km where the total perennial length is 216. The drainage density of 1.25 km/km² for all streams and a density of 0.33 for perennials indicates a moderately dense fluvial network. With a predominant dendritic drainage pattern.
The stream order for the Logan river at its mouth is 5. The stream order of Temple Fork at the confluence of the Logan is 4. Beaver creek also has an order of 4 at its confluence with the Logan.
The Hortonian Law of stream network composition is:
Law of Stream Numbers: The number of streams of a given order is inversely related to their order number. Specifically, the number of streams decreases exponentially as the stream order increases. For each successive stream order, the number of streams is approximately half of the number of streams in the previous order.
Law of Stream Lengths: The average length of streams increases with stream order. First-order streams are the shortest, and with each successive order, the average stream length increases progressively. This law reflects the cumulative nature of stream networks and how smaller tributaries combine to form larger watercourses.
Law of Stream Areas: The average drainage area of streams increases with stream order. As stream order increases, the contributing drainage area becomes larger, reflecting the hierarchical nature of watershed development.
The Logan River follows the 3rd law of stream areas, as the logan progresses, it becomes larger, reflecting the hierarchical nature of watershed development.
Page updated
Google Sites
Report abuse