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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
    ...
    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).
    (view changes)

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
  2. page isleta edited ... {USGS 08331510 RIO GRANDE AT STATE HWY 346 NEAR BOSQUE, NM.png} Annual discharge statistics …
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    {USGS 08331510 RIO GRANDE AT STATE HWY 346 NEAR BOSQUE, NM.png}
    Annual discharge statistics from USGS, 2014. National Water Information System: Web Interface. [Online] Available at: http://waterdata.usgs.gov/nwis.
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    discharge in late Aprillate-April through early Julyearly-July (Figure 9).
    Figure10Figure 10.
    USGS gage 08332010, Rio Grande Floowdway near Bernardo, NM - mean flow (cfs).
    {USGS 08332010 RIO GRANDE FLOODWAY NEAR BERNARDO, NM.png}
    Annual discharge statistics from USGS, 2014. National Water Information System: Web Interface. [Online] Available at: http://waterdata.usgs.gov/nwis.
    The period of record at gage # 08332010 is longer than the other gages in the reach (Figure 10). The 34-, 15-, and 5-year averages show that the amount of water flowing through this gage is decreasing, and that spring flows may be increasing earlier in the year. In the last 5 years, flows at this gage have averaged at or near 0 cfs, intermittently, between Day 201 and 301 (late-August to late-November). This may indicate river drying in the area of this gage, or lower flows, that negatively impact the longitudinal connectivity (i.e. fish and eggs successfully travelling downstream) and lateral connectivity (i.e. availability of instream, side channel, and floodplain RGSM habitat) of the Isleta Reach.
    Longitudinal Connectivity
    The upstream and downstream extents of the Isleta Reach are defined by the Isleta Diversion and San Acacia Diversion Dams (respectively), inhibiting longitudinal connectivity of the Rio Grande. RGSM eggs have been observed throughout the river to drift downstream more than 150 km, but can also settle in low-velocity areas near spawning sites (Medley & Shirey, 2013). Portions of the Isleta Reach are prone to drying during heavy water withdrawals and dry years, limiting longitudinal connectivity further. In particular, MRGESCP (2008) identifies increased drying potential beginning between River Miles (RM) 159 and 160, extending downstream at least as far as RM 153 (Figure 11). The 10-mile segment between the Isleta Diversion Dam, where drying potential is low, and RM 160, leaves little distance for RGSM to spawn and for eggs to drift downstream and entrain in low-velocity habitats. Even as the potential for drying decreases within the 37 miles between RM 151 and the San Acacia Diversion Dam, the channelization of the river can cause RGSM and eggs to flush downstream, without an opportunity to rest or settle in low-velocity areas (MRGESCP, 2008).
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    Adapted from MRGESCP (2008) (Exhibits 2-12, 2-13, 2-14).
    Lateral Connectivity
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    the channel. In the current system, limited overbanking into the floodplain may provide the only habitat that is available for RGSM. Figure 12 shows areas that potentially overbank at specific flows in the Rio Grande.
    and so on...
    FigureFigure12Figure 12. Overbank
    {Isleta Reach, Overbank Flooding.png}
    Adapted from MRGESCP (2008) (Exhibits 4-5, 4-6, 4-7).
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    The 2003 FWS Biological Opinion (BO) describes Reasonable and Prudent Alternatives (RPAs) to avoid the likelihood of jeopardizing RGSM and SWFL, an d of adversely affecting RGSM habitat (FWS, 2003b).
    Opportunities for RGSM
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    MRG indicate thethat there is a need to
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    the main channelchannel, if itthe hydrograph is extended.
    Discussion//Caveats
    There are a number of factors, outside the scope of habitat restoration, that prevent the complete restoration of the Rio Grande to conditions that were present before Spanish imperialist occupation, or even before construction of Cochiti Dam (the northernmost extent of critical habitat for RGSM). In the current Rio Grande system, full habitat restoration is complicated by the extinction of several native aquatic species, as well as development of current technical/engineered, economic, and legal systems in the historic floodplain (MRGESCP, 2004). Further, all observations and studies of RGSM life history and ecology have taken place within current conditions and it's contemporary range. Since the current conditions of RGSM are complicated by anthropogenic development of the floodplain, these observations can lead to a misunderstanding of the RGSM's real habitat preferences and needs (MRGESCP, 2004). Further, low population density and patchy distribution, and a small number of sampling sites, prevent reliable estimates of the RGSM's current population (MRGESCP, 2004).
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    2:42 pm
  3. page isleta edited ... Fish Movement The U.S. Geological Survey (USGS) has installed three stream gages in the Islet…
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    Fish Movement
    The U.S. Geological Survey (USGS) has installed three stream gages in the Isleta Reach above San Acacia Diversion Dam. Focusing on macrohabitat conditions for RGSM, Figures 8, 9, and 10 show annual averages of discharge at these gages.
    FigureFigure8Figure 8. USGS
    {USGS 08331160 RIO GRANDE NEAR BOSQUE FARMS, NM.png}
    Annual discharge statistics from USGS, 2014. National Water Information System: Web Interface. [Online] Available at: http://waterdata.usgs.gov/nwis.
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    and June (Day
    Figure
    (day 75 and 151 of the year) (MRGESCP, 2008). Figure 8 indicates that 6 or 7 year average at U.S. Geologial Survey (USGS) gage # 08331160 has increased spring flows in late April through late early July.
    Figure9Figure
    9. USGS
    {USGS 08331510 RIO GRANDE AT STATE HWY 346 NEAR BOSQUE, NM.png}
    Annual discharge statistics from USGS, 2014. National Water Information System: Web Interface. [Online] Available at: http://waterdata.usgs.gov/nwis.
    FigureAt USGS gage # 08331510, the 7-year average discharge is similar, with increased discharge in late April through early July (Figure 9). Compared to gage # 08331160, flows are about 150 cfs lower.
    Figure10Figure
    10.
    USGS gage 08332010, Rio Grande Floowdway near Bernardo, NM - mean flow (cfs).
    {USGS 08332010 RIO GRANDE FLOODWAY NEAR BERNARDO, NM.png}
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    1:41 pm

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