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Tuesday, November 21

  1. page Fluvial geomorphology 2 edited ... 2. History of the Fluvial Geomorphology Field Fluvial Geomorphology has its roots in the fiel…
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    2. History of the Fluvial Geomorphology Field
    Fluvial Geomorphology has its roots in the fields of engineering and geoscience that have progressed over the past two centuries. In essence Fluvial Geomorphology is the study of landscapes formed from a flowing body of water. Geomorphology is a sub discipline of geoscience and holds a closer relationship to contemporary Fluvial Geomorphology. In its essence, geoscience adheres to the inductive scientific method of observation, hypothesis and experimentation. Experimental geoscience is based on a Bacon methodology of conducting research and producing data for future studies (Thorne et al., 1997).In contrast, engineering applies mathematical Newtonian mechanics in order to design structures and systems to promote quality of human life. Since the 18th century engineering design was applied to river systems in order to alleviate flood risk, develop nautical transportation, energy generation and recreational use. The engineering practices provided the framework for early river management, developing laws and standards for water operations. Detention dams, locks and stream channelization were all measures of river control and stabilization but recently have shown costly effects (Gregory, 2008) . Such examples include maintenance cost, bed armoring, sediment loading, non-point source pollution and riparian degradation.
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    processes (1995).
    In management discourse policy makers and legislation aligned engineers and Geomorphologists during the turn of the century. The two schools of thought formed a relationship around water with differing views; the engineer with intervening institutionalized solutions and the Geomorphologist with long-term independent observations. Together the field of Fluvial Geomorphology has evolved with the bond between the two camps over numerous case projects.
    Table 1: Comparison of skills in Fluvial Geomorphology Integration
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Wednesday, August 9

  1. page Stream classification techniques edited ... Level III describes the state of streams and helps measure existing conditions in response to …
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    Level III describes the state of streams and helps measure existing conditions in response to channel change. This level acts as a method to propose prediction methodologies and can be used to aid in restoration efforts. Important variables in order to apply Level III include riparian vegetation, depositional patterns, meander patterns, confinement features, fish habitat indices, flow regime, river size category, debris occurrence, channel stability index, and bank erodibility (Rosgen, 1994).
    The last level of classification in the Rosgen method is Level IV, which describes verification. This level provides specific information on stream processes used to verify various parameters. This level helps “provide sediment, hydraulic and biological information related to specific stream types,” (Rosgen, 1994). Classification at this level requires measurements and observations of sediment transport, bank erosion, channel geometry, biological data, and riparian vegetation data (Rosgen, 1994). See figure 5 for the breakdown of Rosgen’s classification.
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    Rosgen Classification
    Rosgen’s method is currently the most used classification system. Rosgen also discusses applying the system to restoration efforts. Historical data has shown that streams have been changing character due to imposed anthropogenic alterations in order to provide things like flood control, hydro-electric power, and allocation of water rights. These variables used to classify a river are often changed due to these alterations. Therefore, “to restore the “disturbed” river, the natural stable tendencies must be understood to predict the most probable form,” (Rosgen, 1994). Stream classification aids in providing the restoration team with knowledge of how a system’s variables naturally behave.
    Montgomery and Buffington
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Thursday, June 22

  1. 3:55 pm

Tuesday, June 6

  1. page isleta edited ... Hydrology of the Isleta Reach of the Rio Grande River, New Mexico Isleta Reach ... the Isl…
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    Hydrology of the Isleta Reach of the Rio Grande River, New Mexico
    Isleta Reach
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    the Isleta ff Pueblo at
    Infrastructure
    Although the record of human alteration and disturbance of the MRG goes back thousands of years, a more recent history is fraught with examples where humans have attempted to alter the hydrology to mitigate the risk of flooding, provide infrastructure for irrigation, procure water resources for future consumption, and recreation (Reclamation, 2009).The 20th century brought more severe alterations to the landscape comparatively, “Initially, only small channel modifications occurred, but beginning in the twentieth century, large channel-realignments, miles of levees and jetty fields, numerous diversion dams and large dams were constructed” (Massong, Makar, & Bauer, 2010, p. 4).
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  2. page isleta edited ... Hydrology of the Isleta Reach of the Rio Grande River, New Mexico Isleta Reach ... the Isl…
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    Hydrology of the Isleta Reach of the Rio Grande River, New Mexico
    Isleta Reach
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    the Isleta ff Pueblo at
    Infrastructure
    Although the record of human alteration and disturbance of the MRG goes back thousands of years, a more recent history is fraught with examples where humans have attempted to alter the hydrology to mitigate the risk of flooding, provide infrastructure for irrigation, procure water resources for future consumption, and recreation (Reclamation, 2009).The 20th century brought more severe alterations to the landscape comparatively, “Initially, only small channel modifications occurred, but beginning in the twentieth century, large channel-realignments, miles of levees and jetty fields, numerous diversion dams and large dams were constructed” (Massong, Makar, & Bauer, 2010, p. 4).
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Wednesday, February 10

Monday, December 8

Friday, May 16

  1. page isleta edited ... Adapted from MRGESCP (2008) (Exhibits 2-12, 2-13, 2-14). Lateral Connectivity ... Rio Gran…
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    Adapted from MRGESCP (2008) (Exhibits 2-12, 2-13, 2-14).
    Lateral Connectivity
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    Rio Grande.
    and so on...
    Considering the discharges that have been observed at the ages in the reach (Figures 8, 9, 10), and their location within the reach (RM 164, RM 141, and RM 131, respectively) indicate that there is little overbanking. Figure 12 indicates that overbanking is expected to occur at 3,000 cfs between RM 166 and 165, RM 147 and 145, and RM 144 and 143. The mean flows since at least 1970 indicate that flows do not regularly exceed this amount through the Isleta Reach. Therefore, RGSM habitat, in most years, is limited to the main channel or directly adjacent to it.
    Figure12Figure 12. Overbank Flooding in the Isleta Reach, New Mexico.
    {Isleta Reach, Overbank Flooding.png}
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    2:52 pm

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