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U.S. Army Corps of Engineers

U.S. Army Corps of Engineers. Alaska District. REGULATORY BRANCH. REGIONAL SUPPLEMENT TO 1987 MANUAL. REGULATORY. NEED FOR A REGIONAL SUPPLEMENT CONDITIONS IN ALASKA WARRANT UNIQUE PROTOCOLS AND DEFINITIONS. COLD CLIMATE PERMAFROST GLACIAL TILL VOLCANIC ASH VAST SIZE. REGULATORY.

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U.S. Army Corps of Engineers

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  1. U.S. Army Corps of Engineers Alaska District REGULATORY BRANCH REGIONAL SUPPLEMENT TO 1987 MANUAL

  2. REGULATORY • NEED FOR A REGIONAL SUPPLEMENT • CONDITIONS IN ALASKA WARRANT UNIQUE PROTOCOLS AND DEFINITIONS. • COLD CLIMATE • PERMAFROST • GLACIAL TILL • VOLCANIC ASH • VAST SIZE

  3. REGULATORY

  4. REGULATORY

  5. REGULATORY COE/EPA JOINT CWA DEFINITION OF WETLANDS THOSE AREAS THAT ARE INUNDATED OR SATURATED BY SURFACE OR GROUND WATER AT A FREQUENCY AND DURATION SUFFICIENT TO SUPPORT, AND UNDER NORMAL CIRCUMSTANCES DO SUPPORT, A PREVALENCE OF VEGETATION TYPICALLY ADAPTED FOR LIFE IN SATURATED SOIL CONDITIONS

  6. REGULATORY • 1987 Manual remains umbrella document •  3-Parameter Approach “mandatory” •  Criteria and Definitions associated with • Hydric Soils, Hydrophytic Vegetation and Wetland Hydrology remain the same or similar • The new methodology supplements the Manual and supersedes or updates appropriate Sections and Definitions

  7. REGULATORY BACKGROUND CONGRESS REQUESTED NATIONAL SCIENCE FOUNDATION STUDY AND FULLY FUNDED THE RESEARCH. USACE HQ APPROVED A PLAN DEVELOPED BY ERDC (formerly WES) TO REGIONALIZE THE MANUAL PUBLIC NOTICE ISSUED SOLICITING COMMENTS ON JUNE 28, 2005

  8. REGULATORY AUTHORITY IN 1995, THE NATIONAL RESEARCH COUNCIL OF THE NSF PUBLISHED A REPORT CRITIQUING THE 1987 WETLAND DELINEATION MANUAL. IT VALIDATED THE 3-PARAMETER/CHARACTERISTIC APPROACH BUT CONCLUDED THAT DELINEATION METHODOLOGY SHOULD BE REGIONALIZED.

  9. REGULATORY • Obvious Differences/Changes • New Field Indicators will replace old ones • New Field Data Form will replace old one • New method for determining prevalence of hydrophytic vegetation • Growing Season Definition/Determination • New Problem Areas added as “Difficult Wetland Situations in Alaska”

  10. REGULATORY Differences/Changes Table 1-1. Sections of the Corps Manual replaced by this Regional Supplement for applications in Alaska. Item - Replaced Portions of the Corps Manual - Replacement Guidance (Supplement) Hydrophytic Vegetation Indicators - Paragraph 35, all subparts, and all references to specific indicators in Part IV. Chapter 2 Hydric Soil Indicators - Paragraphs 44 and 45, all subparts, and all references to specific indicators in Part IV. Chapter 3 Wetland Hydrology Indicators - Paragraph 49(b), all subparts, and all references to specific indicators in Part IV. Chapter 4 Growing Season Definition – Glossary. Chapter 4, Growing Season; Glossary Hydrology Standard for Highly Disturbed or Problematic Wetland Situations - Paragraph 48, including Table 5 and the accompanying User Note in the online version of the Manual. Chapter 5, Wetlands that Periodically Lack Indicators of Wetland Hydrology, Procedure item 2(e)

  11. REGULATORY Hydrophytic Vegetation

  12. REGULATORY • Hydrophytic Vegetation • Familiar Terms: • Indicator Status – UPL, FACU, FAC, FACW, OBL • Use of most recent Plant List • Prevalence/Dominance Definition

  13. REGULATORY Hydrophytic Vegetation Prevalence/Dominance Definition: Dominant plant species are those that contribute more to the character of a plant community than other species present, as estimated or measured in terms of some ecological parameter or parameters.

  14. 87 Manual Primary Indicator: More than 50% of the dominant vegetation must be FAC, FACW or OBL (usually determined using the “50/20 Rule” from 1989 Corps Wetland Manual) Visual Observation Morphological Adaptations Technical Literature Physiological Adaptations Reproductive Adaptations Supplement Indicator 1: Prevalence Index (< 3) , also based on indicator status Indicator 2: Wetland Cryptogams –currently only for Black Spruce Forests in Interior and Southcentral Sub regions Indicator 3: Morphological Adaptations Visual Observations (limited) REGULATORY Hydrophytic Vegetation Indicators

  15. REGULATORY BENEFITS OF THE PREVALENCE INDEX • No need to identify strata ( avoids calling low frequency species dominant just because they’re only species in stratum); • Uses absolute cover, not relative (easier to check other’s data); • Don’t have to list in order of frequency or percent cover, easier to complete data sheet in field; • More sensitive to situations with a lot of low cover species

  16. REGULATORY THE PREVALENCE INDEX OBL spp. ___ x 1 = ___ FACW spp. ___ x 2 = ___ FAC spp. ___ x 3 = ___ FACU spp. ___ x 4 = ___ UPL spp. ___ x 5 = ___ Total ___(A) ___(B) P.I. = B/A [Note: If P.I. < 3.00, then Hydrophytic]

  17. REGULATORY THE PREVALENCE INDEX OBL spp. _10__ x 1 = _10__ FACW spp. _20__ x 2 = _40__ FAC spp. _30__ x 3 = _90__ FACU spp. _30__ x 4 = _120__ UPL spp. _0__ x 5 = _0__ Total _90__(A) _260_ (B) P.I. = B/A = 2.89 [Note: If P.I. < 3.00, then Hydrophytic]

  18. Old – Buttressing, Pneumatophores, Adventitious Roots, Shallow Root System, Inflated leaves/stems (Aerenchyma), Polymorphic Leaves, etc. New – Growth Form of Dominant Plants such as stunting or reduced vigor due to stress REGULATORY Morphological Adaptations

  19. REGULATORY Visual Observation Visual observation of plant species growing in areas of prolonged inundation and/or soil saturation. This indicator can only be applied by experienced personnel who have accumulated information through several years of field experience and written documentation that certain species commonly occur in areas of prolonged inundation and/or soil saturation during the growing season.

  20. REGULATORY Visual Observation This indicator may still be used in “Wetlands That Lack Indicators of Hydrophytic Vegetation” also known as “FACU Dominated Wetlands.” The supplement provides a protocol for use of this indicator in Chapter 5, Difficult Wetland Situations. Examples include paper birch, white spruce, Sitka spruce, devil’s club, and field horsetail as dominants in wetlands.

  21. REGULATORY Hydrophytic Vegetation Questions?

  22. REGULATORY Hydric Soils

  23. REGULATORY Hydric Soils Indicators ’87 ManualSupplement Organic Soils A1-Histosol Histic epipedons A2-Histic epipedon Sulfidic material A4-Hydrogen sulfide Aquic moisture regime None Reducing soil conditions a,a-dipyridil Soil colors: Gleyed soils A13-Alaska Gley Bright mottles/ A14-Alaska Redox Low Chroma A12-Thick Dark “A” Hydric soils list None Iron & manganese concretions None None A15-AK Gley Pores

  24. ALASKA GLEYED

  25. ALASKA REDOX

  26. ALASKA GLEY PORE

  27. THICK DARK “A”

  28. REGULATORY Hydric Soils Indicators Additional Hydric Soil Indicators from the Regional Supplement: TA4 – Alaska Color Change (Southeast) TA5 – Alaska Alpine Swales Alaska Redox with 2.5Y Hue Alaska Gleyed without Hue 5Y or Redder Underlying Layer *Note: These indicators are found in the subsection entitled “Hydric Soil Indicators for Problem Soils”

  29. REGULATORY Hydric Soils Questions?

  30. REGULATORY Wetland Hydrology

  31. REGULATORY Wetland Hydrology Old – 6 Primary and 4 Secondary Field Indicators: PrimarySecondary Inundation Oxidized Soil Saturation Rhizosperes Watermarks FAC Neutral Drift Lines Water Stained Sediment Deposits Leaves Drainage Patterns Soil Survey* *deleted indicator

  32. REGULATORY Wetland Hydrology New – 13 Primary and 10 Secondary Indicators: Group A - Observation of Surface or Saturated Soils Group B - Evidence of Recent Inundation Group C - Evidence of Recent Soil Saturation Group D – Evidence from Other Site Conditions or Data

  33. New Hydrology Indicators • Group A: Observation of Surface Water or Saturated Soils: • A1 - Surface water – primary* • A2 - High water table – primary* • A3 – Saturation – primary* * Note: Same as “old” indicator

  34. New Hydrology Indicators • Group B: Evidence of Recent Inundation • B1 - Water marks – primary* • B2 - Sediment deposits – primary* • B3 - Drift deposits – primary* • B4 - Mat or Crust of algae or marl – • primary • B5 - Iron deposits - primary • B6 - Surface soil cracks - primary

  35. HYDROLOGY Mat or Crust of Algae or Marl

  36. HYDROLOGY Iron Deposit

  37. HYDROLOGY Surface Cracks

  38. New Hydrology Indicators • Group B: Evidence of Recent Inundation (continued) • B7 - Inundation visible on aerial imagery - primary • B8 - Sparsely vegetated concave surface - primary • B9 - Water stained leaves – secondary* • B10 - Drainage patterns – secondary*

  39. HYDROLOGY Sparsely Vegetated Concave Surface

  40. New Hydrology Indicators • Group C: Evidence of Recent Soil saturation • C1 - Hydrogen sulfide odor - primary • C2 - Dry season water table - primary • C3 - Oxidized rhizospheres along living roots – secondary*

  41. HYDROLOGY Hydrogen Sulfide H2S – Rotten egg odor Indicator of “real-time” hydrology in the soil

  42. HYDROLOGY Dry Season Water Table For certain localities precipitation data may be complete enough to synthesize information on high water tables. This data may be used during the “drier season” as a positive hydrology indicator.

  43. New Hydrology Indicators • Group C: Evidence of Recent Soil Saturation (continued) • C4 - Presence of reduced iron – secondary • C5 - Salt deposits - secondary

  44. HYDROLOGY Presence of Reduced Iron

  45. HYDROLOGY Salt Deposits

  46. New Hydrology Indicators • Group D: Evidence from Other Site Conditions or Data • D1- Stunted of stressed plants - secondary • D2 - Geomorphic position - secondary • D3 - Shallow aquitard - secondary

  47. HYDROLOGY Stunted or Stressed Plants

  48. HYDROLOGY Geomorphic Position on the Landscape

  49. HYDROLOGY Shallow Aquitard Impermeable or slowly permeable layers near the soil surface Example: Permafrost, shallow bedrock, clay layer

  50. Group D: Evidence from Other Site Conditions or Data (continued) • D4 - Microtopographic relief – seconday • D5 - FAC-neutral test – secondary* May also use data to support Group D indicators for localized conditions

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