RIPARIAN AREA MANAGEMENT Proper Functioning Condition Assessment for Lotic Areas ...

194 Pages·2012·4.8 MB·English

AGENCY REVIEW DRAFT

RIPARIAN AREA MANAGEMENT

Proper Functioning Condition
Assessment for Lotic Areas
TR 1737‐15 v.2, 2013
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AGENCY REVIEW DRAFT

Riparian Area Management

Proper Functioning Condition 
 Assessment for Lotic Areas 

Melissa Dickard   Steve Smith 
Work Group Leader  Team Leader 
Aquatic Ecologist   Riparian Ecologist 
Bureau of Land Management  Bureau of Land Management 
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National Operations Center  National Riparian Service Team 
Denver, Colorado  Prineville, Oregon 

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Mark Gonzalez  Janice Staats 
Riparian/Wetland Ecologist (Soils)  Hydrologist 
Bureau of Land Management  U.S. Forest Service 
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National Riparian Service Team  National Riparian Service Team  
Prineville, Oregon  Prineville, Oregon 

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Wayne Elmore  Paul Summers  
Riparian Ecologist  Ground water Hydrologist 
Bureau of Land Management (Retired)  Bureau of Land Management 
Prineville, Oregon  D National Operations Center 
  Denver, Colorado 
Steve Leonard   
Riparian Ecologist  Dave Weixelman 
Bureau of Land Management (Retired)  Riparian Ecologist 
Midvale, Idaho  U.S. Forest Service 
  Nevada City, California 
Dave Smith   
Hydrologist  Sandra Wyman 
U.S. Fish and Wildlife Service  Rangeland Management Specialist 
Flagstaff, Arizona  Bureau of Land Management 
  National Riparian Service Team 
  Prineville, Oregon 

Technical Reference 1737‐15 v.2, 2013
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Abbreviation list
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3 BLM - Bureau of Land Management
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5 DMA – Designated Monitoring Area
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7 FAC – Facultative species
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9 FACU – Facultative Upland species
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11 FACW – Facultative Wetland species
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13 FAR – Functional-at-risk
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15 FWS – Fish and Wildlife Service F
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17 ID – Interdisciplinary
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19 GIS – Geographic Information System
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21 MIM – Multiple Indicator Monitoring
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23 NF - Nonfunctional
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25 NRCS – National ResourceDs Conservation Service
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27 OBL – Obligate Wetland species
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29 PFC – Proper Functioning Condition, either the method or the rating determination
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31 TR – Technical Reference
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33 UPL – Obligate Upland species
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35 USFS – United States Forest Service
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37

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Table of Contents
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3 Abbreviation list ............................................................................................................... ii 
4 List of Figures .................................................................................................................. v 
5 List of Tables ...................................................................................................................vi 
6 1. Introduction ................................................................................................................. 1 
7 2. Intended Applications .................................................................................................. 6 
8 3. Instructions for Completing the PFC Assessment—Step 1: Identify Assessment Area
9 and Assemble Interdisciplinary Team .............................................................................. 8 
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10 A.  Identify Assessment Area................................................................................... 8 
11 B.  Assemble ID Team – Skills and Training Requirements .................................... 9 
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12 4. Step 2: Review Existing Information and Delineate and Stratify Reaches ................. 11 
13 A.  Gather and Review Existing Information .......................................................... 11 
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14 B.  Delineation and Stratification............................................................................ 12 
15 5. Step 3: Determine Reach Potential ........................................................................... 20 
16 A.  Determine key attributes andR processes .......................................................... 20 
17 B.  Potential and Altered Potential ......................................................................... 23 
18 C.  Determine Potential of Stream Reaches .......................................................... 28 
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19 6. Step 4: Complete PFC Assessment .......................................................................... 32 
20 A.  Plan the Assessment Approach ....................................................................... 32 
21 B.  Complete Reach Information and PFC Assessment Forms ............................. 33 
22 C.  Making the Functional Rating ........................................................................... 33 
23 D.  Using Quantitative Data to Validate Assessment Items ................................... 40 
24 E.  Finalize the PFC Assessment .......................................................................... 41 
25 8. Assessment Items ..................................................................................................... 42 
26 A.  Hydrology ......................................................................................................... 43 
27 Item 1: Floodplain is inundated in “relatively frequent” events. ................................... 46 
28 Item 2: Beaver dams are stable. ................................................................................ 50 
29 Item 3: Sinuosity, width/depth ratio, and gradient are in balance with the landscape
30 setting (i.e., landform, geology, and bioclimatic region). ............................................. 54 
31 Item 4: Riparian area is expanding or has achieved potential extent. ........................... 60 
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1 Item 5: The watershed is not contributing to riparian impairment. ............................. 64 
2 B.  Vegetation ........................................................................................................ 67 
3 Item 6: There is stabilizing riparian vegetation for recovery/maintenance. ................. 70 
4 Item 7: There is recruitment of stabilizing riparian vegetation for recovery/maintenance.
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6 Item 8: Species present indicate maintenance of riparian soil‐moisture characteristics. 76 
7 Item 9: Plant communities that have root masses capable of withstanding high
8 streamflow events are present along the streambank. ................................................ 79 
9 Item 10: Riparian plants exhibit high vigor. ............................................................... 82 
10 Item 11: Adequate stabilizing riparian vegetative cover is present to protect banks and
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11 dissipate energy during high flows. ........................................................................... 84 
12 Item 12: Plant communities are an adequate source of woody material for
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13 maintenance/recovery. ............................................................................................ 88 
14 C. Geomorphology .................................................................................................... 90 
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15 Item 13: Floodplain and channel characteristics (i.e., rocks, woody material, vegetation,
16 floodplain size, overflow channels) are adequate to dissipate energy. .......................... 93 
17 Item 14: Point bars are revegetatinRg with stabilizing riparian plants. ......................... 97 
18 Item 15: Stream banks are laterally stable. .............................................................. 103 
19 Item 16: Stream system is not incising. .................................................................... 108 
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20 Item 17: Stream is in balance with the water and sediment that is being supplied by the
21 drainage basin (i.e., no excessive erosion or deposition). ........................................... 113 
22 9. Instituting the Riparian Management Process ......................................................... 116 
23 Step 5: Determine Resource Values ........................................................................ 117 
24 Step 6: Develop Goals and Prioritize Actions .......................................................... 117 
25 Step 7: Collect Baseline Data & Establish or Modify Objectives .............................. 118 
26 Step 8: Implement Planned Actions ......................................................................... 120 
27 Step 9: Monitor Effectiveness of Actions – Update PFC Status ............................... 120 
28 Step 10: Implement Adaptive Actions as Necessary ............................................... 121 
29 References .................................................................................................................. 122 
30 Glossary ...................................................................................................................... 132 
31 Appendix A—Instructions and Forms .......................................................................... 136 
32 Appendix B—Rosgen Classification System ............................................................... 150 
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1 Appendix C—Example Assessment ............................................................................ 152 
2 Appendix D—Applying Potential to Human-altered Stream Reaches ......................... 164 
3 Appendix E—Quantitative Measures for Assessment Items ....................................... 168 
4 Appendix F—Ground Water/Surface Water Interactions ............................................. 177 
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List of Figures
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7 Figure 1. Schematic drawing of a riparian area. .............................................................. 1 
8 Figure 2. Stream Functions Pyramid, adapted from Harman et al. 2012. ........................ 3 
9 Figure 3. Steps for Completing the PFC Assessment ..................................................... 8 
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10 Figure 4. Alternating complexes within a valley segment. ............................................. 16 
11 Figure 5. Lotic (complex A) and lentic (complex B) complexes alternate within an
12 assessment reach. ......................................................F.................................................. 17 
13 Figure 6. Succession of states for alluvial valley-bottom type. ...................................... 22 
14 Figure 7. Headcut is moving up through a meadow, making the area above functional-
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15 at-risk. ........................................................................................................................... 35 
16 Figure 8. Example of succession as it relates to stream recovery and function. ........... 38 
17 Figure 9. Stream cross sections depicting the states displayed in Figure 8. ................. 39 
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18 Figure 10. Conducting monitoring at a DMA. ................................................................ 40 
19 Figure 11. Stream channel cross-section with important flow features identified. ......... 46 
20 Figure 12. Very stable beaver dam covered with a thick growth of herbaceous and
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21 woody vegetation. ......................................................................................................... 51 
22 Figure 13. Beaver dam totally overgrown with woody riparian vegetation. .................... 52 
23 Figure 14. Low stature beaver dam constructed with cattail and bulrush stems, .......... 52 
24 Figure 15. Stream length (yellow line) and valley length (red line) used to calculate
25 stream sinuosity. ........................................................................................................... 55 
26 Figure 16. Stream channel cross-section showing bankfull width and current active
27 discharge width. ............................................................................................................ 55 
28 Figure 17. The Colorado River in Dead Horse Point State Park, Utah, has a sinuosity
29 close to 1.0 .................................................................................................................... 56 
30 Figure 18. Example of riparian area expansion 1992, 1998. ......................................... 60 
31 Figure 19. Channel narrowing due to riparian area expansion, 1977, 1984, 2008. ....... 61 
32 Figure 20. Example of (A) a mid-channel bar and (B) an overloaded point bar. ............ 65 
33 Figure 21. Age class population distribution forms. ....................................................... 75 
34 Figure 22. Baltic rush exhibiting highly stabilizing root masses. ................................... 80 
35 Figure 23. The shrubs to the left of the fence line show high vigor while those to the
36 right of the fence line do not. ......................................................................................... 83 
37 Figure 24. Lane/Borland balance. ................................................................................ 91 
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1 Figure 25. Overflow channel (A) adjacent to a stream (B). ............................................ 95 
2 Figure 26. Eroded point bar with vertical bank. ............................................................. 97 
3 Figure 27. Idealized cross-section through a point bar. ................................................. 98 
4 Figure 28. Point bars colonized with riparian vegetation. ............................................ 100 
5 Figure 29. Point bar and establishment of vegetation. ................................................ 101 
6 Figure 30. Schematic, planimetric view of idealized point bar features. ...................... 101 
7 Figure 31. The typical stable streambank. ................................................................... 104 
8 Figure 32. Planimetric view illustrates the contrast between idealized stable and
9 unstable bank margins. ............................................................................................... 105 
10 Figure 33. Bank erosion in an unstable channel. ........................................................ 105 
11 Figure 34. Irregular bank margins (white dotted line). ................................................. 105 
12 Figure 35. Landform-controlled streams have little opportunity to move laterally. ....... 106 
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13 Figure 36. Schematic diagrams illustrating the relations between channel cross-
14 sectional area and discharges of different recurrence interval. ................................... 109 
15 Figure 37. Longitudinal gradient of a stream across (A) a knickpoint, and across (B) a
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16 knickzone. ................................................................................................................... 110 
17 Figure 38. Steps for completing the PFC assessment ............................................... 116 
18 Figure 39. Recommended steps for IncorporaAting PFC into management .................. 117 
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List of Tables
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21 Table 1. Hierarchy of stratification levels and possible data sources ............................ 19 
22 Table 2. Attributes/processeDs list. ................................................................................. 20 
23 Table 3. Indicator categories ......................................................................................... 77 
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1. Introduction
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3 Riparian areas are transitional areas regularly influenced by fresh water, normally
4 extending from the edges of water bodies to the edges of upland communities (Naiman
5 et al. 2005) (Figure 1). They reflect interactions between aquatic and terrestrial
6 components of a landscape, and are where hydrology, vegetation, and soils come
7 together on a stream to influence physical function. These areas exhibit vegetation or
8 physical characteristics reflective of permanent surface or subsurface water influence.
9 Ephemeral streams or washes that do not exhibit the presence of vegetation dependent
10 upon free water in the soil are not included.
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11 This technical reference addresses the physical functioning of perennial or intermittent
12 lotic (flowing water) riparian systems, such as rivers or streams. Lentic (still or very
13 slow water) riparian systems, such as wetlands, ponds, or marshes, are addressed in
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14 TR 1737-16. This technical reference provides instructions for the application of the
15 PFC protocol. It is not intended to serve as a textbook addressing every aspect of
16 stream and riparian function and ecology. A
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18 Figure 1. Schematic drawing of a riparian area.
19 Riparian areas are complex, dynamic ecosystems incorporating biological, physical, and
20 chemical processes. The Proper Functioning Condition (PFC) assessment method was
21 created to qualitatively evaluate the foundation of these process—specifically the
22 functionality of the physical processes occurring on a stream. These physical
23 processes include the interactions of hydrology, stabilizing vegetation, and
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1 geomorphology. Professionals with background in these subjects assess the stream
2 together as an interdisciplinary team (ID team). Because the PFC assessment
3 compares each stream to its own potential, it is universally applicable to all but the most
4 highly modified perennial and intermittent streams.
5 The term PFC is used to describe both the assessment process, and a defined, on-the-
6 ground condition of a riparian area. The on-the-ground condition termed PFC refers to
7 how well physical processes are functioning. A system in PFC displays a resilience that
8 will allow the riparian area to remain reasonably intact during high-flow events (such as
9 the 5-, 10- or 25-year flow), and recover quickly, with a high degree of reliability.
10 The PFC assessment refers to a consistent approach for considering hydrologic,
11 vegetation, and geomorphic attributes and processes to assess the condition of riparian
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12 areas at a point in time. An assessment form (Appendix A), synthesizes information that
13 is foundational to determining the physical functioning of a riparian system. Following
14 completion of the assessment form, the stream reach Fis placed in one of three rating
15 categories:
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Proper Functioning Condition (PFC): A lotic riparian area is considered to be in
PFC, or “functioning properly” when adequate vegetation, landform, or large woody
material is present to:
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• Dissipate stream energy associated with high waterflow, thereby reducing erosion
and improving water quality.
• Filter sediment, capture bedload, and aid floodplain development.
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• Improve flood-water retention and ground-water recharge.
• Develop root masses that stabilize streambanks against erosion.
• Maintain channel characteristics.

Functional—At Risk (FAR): Riparian areas that are in functional condition, but an
existing landform, water, or vegetation attribute makes them susceptible to impairment.
Nonfunctional (NF): Riparian areas that clearly are not providing adequate
vegetation, landform, or large woody material to dissipate stream energy associated
with high flows, and thus are not reducing erosion, improving water quality, etc.
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18 The physical functionality of a riparian area is the foundation of stream processes
19 (Figure 2). Physical attributes and processes of the stream exist in a hierarchical
20 relationship with chemical processes and biological processes. The dotted lines around
21 each stratum indicate that each level of the pyramid interacts with the adjoining levels.
22 The arrows indicate the direction of influence. Although biological and chemical
23 processes act upon physical function, the majority of the cause-and-effect relationships
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1 flow upward through the pyramid. Stream processes are underlain by geology and
2 climate.
3 If the riparian area is functioning properly, then it is capable of producing good water
4 quality and suitable habitat. If, on the other hand, the riparian area is not functioning
5 properly, it is likely that chemical processes, such as the production of good water
6 quality, and biological processes, such as the creation of suitable habitat will also be
7 impaired (Harman et al. 2012, Shields et al. 2010). However, PFC does not guarantee
8 that chemical and biological processes are functioning well. For example, sediment,
9 thermal, or nutrient regimes could remain impaired because of upstream impacts that
10 are transmitted downstream. If a parameter representing a biological or chemical
11 process, such as habitat complexity, is of interest, the ID team should use a protocol
12 specifically intended to assess that parameter, in conjunction Twith the PFC assessment.
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Biological

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Chemical

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Physical

      (Hydrology, Stabilizing Vegetation, Geomorphology)

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              Geology                                               Climate
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15 Figure 2. Stream Functions Pyramid, adapted from Harman et al. 2012.
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17 An interdisciplinary team must possess an understanding of stream dynamics and
18 potential to accurately complete the assessment, and discussion among experts using
19 their professional experience and judgment is key to producing a quality product. So,
20 although PFC relies on basic concepts of stream function, it cannot be completed by a
21 non-professional after a half-day training. PFC involves both the art and the science of
22 “reading the stream,” and a working understanding of each takes time to develop.
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