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PART 1

RAPIDASSESSMENT

METHOD

Oregon Plan for Salmon & Watersheds

OREGON DEPARTMENT OFS T AT E L A N D S

Hydrogeomorphic (HGM) Assessment Guidebookfor Tidal Wetlands of the Oregon Coast, Part 1:Rapid Assessment Method

Paul Adamus, Ph.D., Adamus Resource Assessment, Inc., Corvallis, OR 97330; [email protected] 2006

produced byCoos Watershed AssociationP.O. Box 5860Charleston, OR 97420541.888.5922 (phone)541.888.6111 (fax)[email protected] Souder, Executive Director

author’s acknowledgements

Copyright © 2006 by the Coos Watershed Association. This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/1.0/ or send a letter to Creative Commons, 559 Nathan Abbott Way; Stanford, CA 94305, USA.

photographs byPaul AdamusRussell ScrantonAdam Demarzo

suggested citationAdamus, P.R. 2006. Hydrogeomorphic (HGM) Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1: RapidAssessment Method. Produced for the Coos Watershed Association, Oregon Department of State Lands, and U.S.E.P.A.-Region10. Charleston, OR: Coos Watershed Association.

the Coos Watershed Association......is a 501(c)(3) non-profit organization whose mission is “to provide a framework to coordinate andimplement proven management practices, and test promising new management practices, designed tosupport environmental integrity and economic stability for communities of the Coos watershed.” TheAssociation, founded in 1994, works through a unanimous consensus process to support the goals of theOregon Plan for Salmon and Watersheds. Our 20 member Executive Council includes representatives from

agricultural, small woodland, waterfront industries, fisheries, aquaculture, local government, environmental industrialtimberland, and state and Federal land managers.

A practical need for a method to rapidly assess Oregon’s tidal wetlands was first identified by Jon A. Souder, Ph.D., ExecutiveDirector of the Coos Watershed Association (CWA), who procured funding for the project and served as project administrator.Funding came primarily through a competitive grants program of the US Environmental Protection Agency (Region 10, YvonneVallette). The project has been implemented as an independent component of EPA’s West Coast Tidal Monitoring Venture.Under the guidance of Janet Morlan, the Oregon Department of State Lands (Wetlands Program) provided additional assis-tance, funding, and coordination. Outstanding for their voluntary assistance, equipment loans, data sharing, and good advicehave been the staff of South Slough NERR (notably Steve Rumrill, Craig Cornu, Sue Powell, and Michele Koehler), as well asDan Bottom, Laura Brophy, Larry Caton, Gareth Ferdun, Bob Frenkel, Jim Good, Neal Hadley, Jon Hall, Roy Lowe, Neal Maine,Jim Mundell, Lori Robertson, Heather Stout, participants at the “tidal wetland experts workshop,” the Tenmile WatershedCouncil, and the hundreds of landowners who said “yes” to our requests to access their properties. Also appreciated havebeen the contributions of John Baham, Jamie Carter, Leandra Cleveland, Greg Coffeen, Nick Coffey, Trevan Cornwell, JohnChristy, Adam Demarzo, Ralph Garono, Ren Jacob, David King, Pete Klingeman, Emily Kolkemo, Jennifer Larsen, BradLivingston, Jay Lorenz, Tonya Haddad, Jennifer Taylor Hennessey, Justin Miner, Karen Nelson, Nancy Nichols, MikePatterson, Phil Quarterman, Doug Ray, Migs Scalici, Russell Scranton, Miranda Shapiro, Stan van de Wetering, and DawnWright. We particularly appreciate and acknowledge the 198 private landowners and public agencies who allowed accessto their wetland properties for this project. We have offered those private landowners a guarantee of confidentiality regardingthe location, details, and functional conditions of their specific sites. We request the users of this guide respect thisconfidentiality.

Paul Adamus, Ph.D., Adamus Resource Assessment, Inc.

produced byCoos Watershed Association

August 2006

Hydrogeomorphic (HGM) Assessment Guidebookfor Tidal Wetlands of the Oregon Coast

Part 1: Rapid Assessment Method

Editor Marty Giles, Sharp Point Writing & Editing Services; Coos Bay, Oregon

Graphics & Layout Designer Anne Farrell-Matthews, South Coast Printing & Graphics; Coos Bay, Oregon

Project Manager Jon A. Souder, Ph.D., Coos Watershed Association; Charleston, Oregon

This project was funded byU.S. Environmental Protection Agency Grant #CB9702800-1

to the Oregon Department of State Lands.

This project was managed bythe Coos Watershed Association under a Cooperative Agreementwith the Oregon Department of State Lands, dated June 20, 2002.

Additional support to the Coos Watershed Associationfor their work on this project was provided by

Oregon Watershed Enhancement Board (OWEB) Grants #204-010 and #206-010.

OREGON DEPARTMENT OFS T A T E L A N D S

1August 2006 – Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1

This is the first of a five part assessmentguide for tidal wetlands of the OregonCoast. This document presents a methodfor assigning scores to a tidal wetland basedon twelve functions‡ that are (potentially)performed naturally by wetlands. Thismethod also assesses: 1) the potentialvalues‡ of these functions, 2) the indicators‡

of a wetland’s biological and geomorphiccondition, and 3) the potential risks‡ to awetland’s integrity‡. Intended for use bytrained natural resource professionals, thismethod can generate usable results from asingle day-long visit to a wetland.

Development of this rapid assessmentmethod (RAM) complied generally withguidelines for developing regionalhydrogeomorphic (HGM)‡ methods asissued by the U.S. Army Corps of Engi-neers in coordination with other agencies.During this method’s development, mul-tiple regional subclasses of the “TidalFringe” wetland class were defined, and thecandidate indicators of functions wereproposed and peer-reviewed in a workshopof regional scientists. Reference data forthese indicators were then collected from120 reference wetlands from the Californiaborder north to, but not including, theColumbia River estuary. The reference datawere subsequently analyzed to help cali-brate the scoring models‡. Perhaps uniqueamong wetland rapid assessment methods,an accompanying spreadsheet appliesregression models to specific sites‡ to setmore realistic expectations for some vari-ables‡, and to partially distinguish humanimpacts to wetland integrity‡ from naturalinfluences. The method also introduces theidea of a “certainty index” for indicator andfunction scores.

This RAM guide allows users to identifywhich of several functions most distinguisha particular tidal wetland from others of its

subclass. Although it is sensitive to differ-ences among different subclasses of tidalwetlands, the method does not allow users tocompare different tidal wetland subclassesdirectly (e.g., high vs. low marsh‡), nor tocompare non-tidal wetlands with tidal wet-lands (e.g., undiked vs. completely-dikedsites). The method is applicable to severalresource management needs, including—

• designing and evaluating tidal wetlandrestoration projects in a consistent,standardized manner

• prioritizing tidal wetlands based on theircondition (level of degradation or integ-rity)—either potential (i.e., risk) or actual

• providing a standardized and transparentprocedure for assessing the capacity of aparticular wetland to perform severalvaluable functions (such as when alter-ations that would require a federal and/orstate wetland permit are proposed)

As far as possible, this method should beused in concert with watershed-scale assess-ments of wetland functions and with more-intensive procedures that monitor individualwetlands over the long term.

Restoration project designers who prefer notto use this RAM may nonetheless find thereference data accompanying the RAM guideuseful. This method is intended to serve asan operational draft and may be revisedat future times in response to user feed-back and evolving scientific understand-ing of tidal wetlands. As of the publicationdate, this document, the supporting files offield and GIS data, and the spreadsheetneeded to compute scores for the rapidassessment method, may be downloadedfrom: www.oregonstate.edu/~adamusp/HGMtidal . Users should regularly check forupdates at this internet location and at theOregon Department of State Lands (DSL)website: www.oregonstatelands.us .

Summary

Summary

‡ Terms defined in Glossary are indicated by a ‡ at first usage in text.

2 Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 – August 2006

For more information about this method and opportunities to be trained in its use, please contact:

Dr. Paul AdamusAdamus Resource Assessment, Inc.6028 NW Burgundy Dr.Corvallis, OR 97330phone: (541) 745-7092email: [email protected]

Janet Morlan, Wetlands Program ManagerOregon Department of State Lands775 Summer St. NE, Ste. 100Salem, OR 97301-1279phone: (503) 378-3805, ext. 236email: [email protected]

Summary


ACKNOWLEDGMENTS INSIDE COVER

SUMMARY 1

CONTENTS 3

1 INTRODUCTION 4

Purpose and Need 4

Background: the HGM Approach for Assessing Wetland Functions 11

2 THE HGM RAPID ASSESSMENT METHOD 14

How to Use the Method 14

Classifying the Wetland 17

Delimiting the Assessment Units 19

Description of Data Forms 23

3 CORRECTLY INTERPRETING AND APPLYING RESULTS

OF THIS METHOD 27

4 LITERATURE CITED 33

APPENDIX A. DATA FORMS 34

Data Form A1. Rapid Indicators of Risks to Tidal Wetland Integrity and Sustainability

Data Form A2. Direct Indicators of Wetland Integrity that Require More-Intensive Field Work

Data Form B1. Rapid Indicators of Function That May be Estimated

Data Form B2. Rapid Indicators of Function Requiring Aerial Photographs or Measuring Equipment

Data Form C. Rapid Indicators of the Values of Functions

Vegetation Quadrat Data Form

APPENDIX B. ABBREVIATIONS USED IN THIS DOCUMENT 72

APPENDIX C. SCORING MODELS AND SCALES USED TOASSESS THE FUNCTIONS SCORING MODELS 73

APPENDIX D. GLOSSARY 76

TABLE OF CONTENTS

Contents


E

E

E

EE

E

J

JJ

J

J

EE

DW

DW

DW

PP

P

J

J

JJ

J

1 Introduction

Purpose and Need

Tidal wetlands are widely recognized for theservices and values they provide to society(Teal 1962, Costanza et al. 1997; also see“Potential functions of tidal marshes of theOregon coast, and their associated values,”page 9). In Oregon, tidal wetlands arevalued for their capacity to passively modifyrunoff before it reaches productive coastalwaters, as well as for their key role in sup-porting salmon and other marine resources(Seliskar & Gallagher 1983, Thom 1982,Good 2000). Yet, not all tidal wetlands areequal: they differ in their intrinsic capacityto provide these vital services and values.They also differ in the degree to which theircapacity to function properly has been

altered by human activities. Understandingand representing fairly these differences isimportant to the people whose land includesor borders tidal wetlands, as well as to thosewho benefit from the values and servicesthese wetlands support. Understanding thesedifferences is also important to agenciesresponsible for managing human activities intidal wetlands, as well as to agencies andgroups interested in restoring or enhancing

their ecological functions.Even among tidal marshes‡

that are relatively pristine,not every marsh performsevery function to the samedegree or consistentlythrough time. Recognizingthis, agencies are increas-ingly attempting to tailortheir wetland managementand regulatory decisions tocharacteristics of individualwetland sites and water-sheds. This fine-tuning ofwetland management isbeing done in the context ofthe overriding national andstate policy objectives ofachieving “no net loss” (ornet gain) of the importantfunctions of America’s andthe states’ wetlands.

What is a RAM?A Rapid Assessment Methodassigns numbers to specific fieldobservations and then organizesthose numbers to quantitativelyevaluate particular functions andvalues.

Figure 1. Aerial infrared photograph of a Nehalem tidal marshshowing geomorphic indicators. The 10 “junctions”(J) measuredalong the longest interval channel; the 8 “exits”(E) of channelsalong the external edge‡; complexes of dozens of marsh pannes‡

(P); and a driftwood (DW) line along the upland edge.

Introduction


1. Rapid AssessmentMethod for Tidal Wet-lands of the OregonCoast

2. Science Review and DataAnalysis Results for TidalWetlands of the OregonCoast

3. Wetland Profiles ofOregon’s Coastal Water-sheds and Estuaries

4. Software and Databasefor Selected Tidal Wet-lands of the OregonCoast

5. Revised Maps of TidalWetlands of the OregonCoast

A method that may be applied during a single visit to assess indicators of thefunctions and condition of a particular tidal wetland relative to others of its subclass.Print document with accompanying spreadsheet program CD-ROM.

A detailed synopsis of literature and data upon which the rapid assessment method ispartially based, with emphasis on research from the Pacific Northwest, includingstatistical analyses of new field data collected for calibrating the rapid assessmentmethod indicated above. Print document.

Tabular and narrative summaries and interpretations, by watershed and estuary, ofthe distribution, properties, and geomorphic settings of wetlands (not just tidalwetlands) as derived from GIS analyses of available spatial data layers. Printdocument.

A CD-ROM containing: a) a spreadsheet that automatically calculates scores forfunctions and condition, b) a database of raw data collected from 120 tidal wetlandsof the Oregon coast, and c) photographs of representative sites on public lands.

A DVD containing refinements of the National Wetlands Inventory maps, specifi-cally: a) increased detail in boundaries of intertidal emergent and intertidal forestedwetlands based on enlarged May 2002 color infrared aerial photographs (1:24,000original scale), field observations, and other data sources; b) labeling of thesewetlands to conform with a hydrogeomorphic classification‡; c) labeling of somenon-tidal wetlands as “Restoration Consideration Area” if they might havegeotechnical potential for restoration of tidal circulation; and d) improved depictionof tidal creeks within some wetlands. The DVD also includes spatial data on otherthemes pertinent to assessing condition and function of Oregon tidal wetlands.Some of this information may also be available at: www.coastalatlas.net orwww.coastalatlas.net/metadata/TidalWetlandsofOregonsCoastalWatersheds.Scranton.2004.htm .

Introduction

To address the need for distinguishing differences among tidal wetlands, a series of five productshas been prepared. Together these products comprise a “Hydrogeomorphic (HGM) AssessmentGuidebook” for tidal wetlands of the Oregon Coast––


The particular rapid assessment methodprovided by this part of the guidebook isapplicable mainly to tidal marshes–herba-ceous emergent wetlands whose salinity mayrange from fresh (less than 0.5ppt salt) tosaline (up to 35ppt salt, rarely above). It alsoencompasses shrub‡ and forested wetlandsthat are occasionally inundated‡ by tides, aswell as narrow tidal channels‡ that existwithin tidal wetlands. Vegetated wetlandsclassified as “Palustrine” on National Wet-land Inventory maps (Cowardin et al. 1979;www.nwi.fws.gov) are included if they areinundated at least monthly. Eelgrass bedsare not included, nor are coastal backdunewetlands, even though their underlying watertable may sometimes be influenced by tidalvariation. Also excluded are other wetlandsthat are not inundated at least annually bytides, such as most marshes located behindtidegated‡ dikes. Tidal wetlands of theColumbia River estuary are not covered bythis method because logistical considerations

prevented collecting data from that region asnecessary for calibrating the scoring models.

The method is intended partly for use inassessing–in a consistent, standardizedmanner–the quality of work in projectsinvolving tidal marsh restoration and cre-ation in Oregon. Assessments of the successor failure of restoration and creation projectsare needed to justify the financial investmentin these projects and to identify ways ofimproving the success of similar futureprojects.

Moreover, there is a need for tools to assesstidal wetland condition (i.e., naturalness of awetland as defined by its water quality,animals, and/or plants) in order to trackpossible degradation of tidal marshes result-ing from gradual urbanization and the cumu-lative effects of other factors in their water-sheds and region. Under Section 401 of thefederal Clean Water Act, states and tribes arejust as responsible for maintaining thequality and beneficial uses of jurisdictionalwetlands as they are for maintaining thequality and designated uses of streams,rivers, lakes, and estuaries.

Figure 2. Example of geodatabase map prepared as part of this HGM project. Such maps wereprepared for all estuaries of the Oregon Coast and are available on the accompanying DVD.

Introduction

Legend Tidal WetlandClassification

Water

Marine Sourced High Tidal Wetland

Marine Sourced Low Tidal Wetland

River Sourced Tidal Wetland

Potential Forested Tidal Wetland

Restoration Consideration Area

Fill

Non Tidal Wetland

Unconsolidated

Upland

DSL Head of Tide

Railroad

1995 Roads

1995 Highway

N

S

EW


The need to assess wetland functions–notjust wetland condition or integrity–is men-tioned explicitly in numerous laws andpolicies of state and federal agencies, e.g.,December 2002 Regulatory Guidance Letterpertaining to Section 404 of the FederalClean Water Act, Oregon Removal-Fill Law,and Oregon Watershed Assessment Manual.The capacity of some functions correlatespositively with the condition or naturalnessof the particular wetland site. Thus, therequirement to assess functions is viewed asgenerally compatible with the requirementfor assessing aquatic life uses (or “wetlandintegrity”) in waters so designated. How-ever, “function capacity‡” and “naturalness”should not automatically be assumed to besynonymous. Exceptions to their generalcorrelation are numerous and important.Moreover, the strength of correlation de-pends strongly on how “naturalness” and“function capacity” are defined and mea-sured. Some ecological goals potentiallyapplicable to Oregon’s tidal marshes areshown in “Components of healthy tidalmarshes,” page 10.

It is hoped that routine use of this guidebookand complementary methods will helpOregon assess the ecological condition forfreshwater wetlands (Morlan 2000) andestuarine systems (Good 2000), as high-lighted in Oregon’s State of the EnvironmentReport 2000—

• change in area, diversity, and distributionof wetland types

• changes in hydrologic characteristics

• changes in water quality

• changes in native wetland plant andanimal assemblages (e.g., changes due toinvasive species)

• degree of connectivity with other aquaticresources and upland‡ habitats

Increasingly, protocols are being publishedthat describe–often in great detail–a particu-

lar researcher’s or group’s opinion on howbest to sample tidal marshes (see Appendix Aof Part 2). Some such protocols are designedspecifically for monitoring restoration sites.However, many fail to demonstrate specifi-cally how the collected data can be manipu-lated so as to characterize the levels offunctions a wetland is performing relative toother wetlands of its type. Consequently,they fail to demonstrate on a site-specificbasis how the collected data relate to specificservices, values, beneficial uses, and end-points important to society. Indeed, somedata collection protocols claim to be measur-ing wetland “function” (singular), as ifsomehow the diverse and sometimes con-flicting functions a wetland performs couldbe unified into one cosmic measure.

This guidebook is not primarily intended toextend our knowledge of tidal wetlands(although some new findings are presented inParts 2 and 3), but rather to compile, orga-nize, and cross-reference existing knowledgein a manner that focuses it effectively intools for assessing tidal wetlands of theOregon Coast. In a national report on wet-land mitigation, the National ResearchCouncil (2001) highlighted a need for theaugmentation of “best professional judgmentapproaches” with procedures that—

• effectively monitor the attainment ofgoals of wetland mitigation projects

• assess a full suite of recognized functions

• incorporate effects of wetland position inthe landscape

• scale the assessment data to data from aseries of reference sites‡

• are sensitive and integrative to changesin performance over a dynamic range ofspace and time

• reliably indicate important wetlandprocesses, or at least, structural indica-tors of those processes

• generate parametric and dimensionedunits, rather than non-parametric rank

Introduction


This method attempts to address all of theabove while still filling the practical need forcompleting a preliminary site assessmentbased on a single visit to a wetland site. Asingle-visit assessment method is neededbecause the Oregon Department of StateLands (DSL) and the U.S. Army Corps ofEngineers, in cooperation with the U.S.Environmental Protection Agency, are re-quired to make hundreds of decisions eachyear regarding applications to alter Oregonwetlands. Each decision must be madewithin a limited time period, sometimes withlittle flexibility to collect data at other sea-sons. Oftentimes, the severely-limitedavailability of personnel, time, and funds donot allow the monitoring agencies or partiesresponsible for these projects to collect moreintensive, robust, and process-oriented fielddata (such as recommended by Zedler &Lindig-Cisneros 2000, Neckles et al. 2002,and others, and as implied by the last of thebulleted items above).

In addition, because wetland decisions areoften controversial, the technical reasons fora particular decision must be explicit andconsistent in order to maintain public trust.

The method presented in this guidebook isintended to make assessments more explicitand consistent, as well as incorporate themost current and relevant scientific knowl-edge. Ideally, the method should be used aspart of a more comprehensive wetlandmonitoring strategy.

A need also exists for site-specific assess-ment methods that address the values offunctions, not just the capacity of thosefunctions. “Values” are the economic,ecological, and social expressions of afunction as a result of context-related oppor-tunity to provide the function and the likelysignificance of the function to local andregional users or resources. Values include,but aren’t limited to, features that some rapidassessment methods call “red flags,” “ser-vices,” or “value added” features. Themethod presented in this guide attempts tocarefully distinguish values from theirfunctions because any function may havemultiple, sometimes conflicting values, and

Although focused mainly on tidal marshes, thisguidebook includes tidal wetlands partiallyforested with Sitka spruce – currently a rare typeon the Oregon Coast.

Introduction


because assessment of values is considerablymore subjective and context-dependent thanassessment of functions. The considerationof values by this guidebook’s method (thisdocument), as well as the data compilationsin the third document in this series, representa response to one of the most frequentcriticisms of wetland assessment methods:that they do not sufficiently address theimportance of wetlands at landscape, water-shed, and regional scales.

Potential functions of tidal marshes of the Oregon coast and theirassociated values

Notes:1. Definitions of these functions and discussions of their values are provided in Part 2 of this guidebook.2. This is not a complete list of functions and values of tidal marshes, but rather a list of functions whose relativecapacity may reasonably be assessed across a set of marshes using a set of characteristics (indicators) that can beassessed rapidly with limited technical skills and equipment. The only function not addressed herein, but described inthe National Guidebook for Application of Hydrogeomorphic Assessment to Tidal Fringe Wetlands (Shafer & Yozzo1998), is Tidal Surge Attenuation. Also, some functions have been aggregated for the sake of practicality. Accuracy ofthe assessments is diminished somewhat by aggregating functions, species, or elements, each with slightly differentrequirements or pathways. If species- or element-specific predictions are needed, users should refer to other assessmentmethods and models.

This guidebook is intended to be used bywetland specialists for government agencies,natural resource organizations, and consult-ing companies–people who are skilled inconducting jurisdictional delineations ofwetlands. Some basic skills in plant identifi-cation are required to address one of thismethod’s 12 functions (Botanical Condi-tion). Users also should be able to recognizefeatures that characterize soils as hydric anddelineate drainage area boundaries from atopographic map‡.

Introduction

function potentially associated values

Produce Aboveground Organic Matter forage for livestock; supporting biodiversity

Export Aboveground Plant & Animal Production supporting commercial fisheries & biodiversity

Maintain Element Cycling Rates and Pollutant minimizing costs for dredging & shore stabilization,Processing; Stabilize Sediment purifying water, supporting commercial fisheries & biodiversity

Maintain Habitat for Native Invertebrates supporting commercial fisheries & biodiversity

Maintain Habitat for Anadromous Fish supporting commercial fisheries & biodiversity

Maintain Habitat for Visiting Marine Fish supporting commercial fisheries & biodiversity

Maintain Habitat for Other Visiting and Resident Fish supporting commercial fisheries & biodiversity

Maintain Habitat for Nekton-feeding Wildlife supporting biodiversity & ecotourism

Maintain Habitat for Ducks and Geese supporting biodiversity & ecotourism

Maintain Habitat for Shorebirds supporting biodiversity & ecotourism

Maintain Habitat for Native Landbirds, supporting biodiversity & ecotourismSmall Mammals, & Their Predators

Maintain Natural Botanical Conditions supporting biodiversity & ecotourism


Large stable logs provide an elevated surface whererelatively salt-sensitive woody plants can germinateand grow in tidal marshes.

(a.k.a.: “good quality,” “intact,” “functionallyequivalent,” “mature,” etc.)

A “healthy” tidal marsh …

• …is inundated at a tidal frequency, duration,season, magnitude, and extent that is characteris-tic for the site’s elevation and position in theestuary.

• …exhibits salinity regimes and experiencesfreshwater inputs in spatial and temporalpatterns that are seasonally and diurnally appro-priate for the site’s vertical and horizontalposition in the estuary.

• …exhibits erosional/depositional regimes andhas sediment particle size distributions that areappropriate for the site’s position in the estuaryand watershed geology/soils.

• …exhibits a channel cross-section and mor-phological complexity, and/or a shoreline slopeand complexity, that is appropriate, at multiplescales, for the age of the site and its geologic/hydrologic setting.

• …receives sustained inputs of characteristicquantities, sizes, and decay classes of largewoody debris.

• …receives inputs of nitrogen, phosphorus, andother naturally-occurring elements in formsand seasonal patterns that are appropriate for thesite’s landscape setting, and converts these inputsbetween inorganic and organic forms (andgaseous forms, for N and C) at rates appropriatefor the age of the site and its elevation, substrate,exposure, and salinity.

• …exhibits levels and decomposition rates of soilorganic matter and dissolved oxygen that areappropriate for the age of the site and its eleva-tion, substrate, exposure, temperature, andsalinity.

• …exhibits a resilient assemblage of nativewetland-associated plants whose speciescomposition, diversity (structural, functional, andtaxonomic), percent-cover, productivity, andpatch heterogeneity/zonation are appropriate forthe age of the site and its elevation, substrate,exposure, and salinity.

• …exhibits a resilient assemblage of nativewetland-associated vertebrates and inverte-brates whose species composition, diversity(both taxonomic and functional), density, tissuecontaminant levels, production, and health areappropriate for the age of the site and its eleva-tion, substrate, exposure, and salinity.

• …is located within characteristic distances ofother tidal marshes and other important estuarinehabitats such as native eelgrass beds and freshwa-ter seeps.

Introduction

Components of healthy tidal marshes

Deeply-incised channels are characteristic ofmany Oregon tidal marshes and provide a cool,sheltered microhabitat for foraging fish.


location or type, or on the typically-recom-mended but problematic approach of com-paring a particular mitigation wetland withmerely a single reference (“control”) site,e.g., Mitchell 1981, Neckles et al. 2002.

The national initiative began with publica-tion of a nationwide scheme for HGMclassification (Brinson 1993), and broadguidance for developing regional HGM-based assessment methods (Smith 1983,Smith et al. 1995, Smith et al. 2001). Subse-quently, “HGM projects” were initiated inover a dozen states, largely with fundingfrom the USEPA. Guidebooks from some ofthese efforts are now available, includingones for assessing functions of tidal wetlandsin other regions (Shafer and Yozzo 1998,Shafer et al. 2002).

In 1997 Oregon’s Department of State Lands,after meeting with other agencies and actingupon a key recommendation of a report(Recommendations for a Nonregulatory

Introduction

Figure 3. Idealized depiction of the configuration of transects, quadrats, andchannel cross-sections used to survey 120 Oregon tidal marshes.

Background: the HGM Approach for Assessing Wetland Functions

Oregon is not unique in attempting to de-velop methods for rapidly assessing thefunctions or condition of tidal wetlands. Inthe early 1990s, the federal agency respon-sible for issuing permits for wetland alter-ation, the U.S. Army Corps of Engineers,announced a “National Action Plan” (FederalRegister 62(119):33607; www.epa.gov/OWOW/wetlands/science/hgm.html) todevelop improved methods for representingthe functions of all wetlands. The newassessment methods would be developedregion-by-region and be organized aroundhydrogeomorphic (HGM) principles forwetland classification. The methods wouldfeature scoring models that would attempt torepresent the relative capacity of a particularwetland to provide each of several functions,as rated on a scale of 0 (low capacity) to 1(high capacity). The model scales would becalibrated using data collected from regionalreference sites. This approach was viewed asa more sophisticated and improved alterna-tive to approaches based simply on wetland


Wetland Restoration Program for Oregon,Good & Sawyer 1998), proposed that Oregonalso begin developing HGM methods andguidebooks appropriate for various regionsof Oregon. A statewide HGM frameworkdescribing Oregon’s wetland types, theirfunctions, and potential indicators of thesefunctions was developed (Adamus 2001b).

From 1998 to 2000, Oregon’s first effort todevelop HGM methods focused on two typesof wetlands common in the WillametteValley (Adamus and Field 2001, Adamus2001a). Field data were collected from 109wetlands belonging to these types and thefirst regional guidebook for Oregon waspublished. Subsequently, regulatory staffs ofthe U.S. Army Corps of Engineers (PortlandDistrict), Oregon Department of State Lands(DSL), various other agencies, and consult-ing firms received training in the WillametteValley HGM method. In January 2003, DSLadopted rule revisions to the Removal-FillLaw which require that applicants for wet-land Removal-Fill permits indicate the HGMsubclass‡ to which the impacted and pro-posed mitigation wetland belong. Oregon’s

HGM guidebook for the Willamette Valleyecoregion‡ provided peer-reviewed, cali-brated models for assessing wetland func-tions in the Willamette Valley, as well as anextensive reference data set for potential usein developing performance standards forwetland restoration projects there. DSL’sadministrative rules currently encourage useof these products for assessing wetlandfunctions in the context of permit decisionsin the Willamette Valley. However, no suchmodels of wetland functions (or region-wide

reference data sets that pertain towetland functions) were produced forother Oregon regions and wetlandtypes.

The project that is the focus of thisguidebook has attempted to fill thatneed for tidal wetlands of the Oregoncoast. Using the terminology ofEPA’s national monitoring strategyfor wetlands, the method presented

Both erosion and deposition are naturally-occurringprocesses in tidal marshes.

Introduction


herein may be considered a “Tier 2”method1. No rapid methods are available forassessing tidal wetlands in neighboringWashington, but California has recentlydrafted a method, California Rapid Assess-ment Method, or CRAM (Collins et al.2004), that includes an assessment compo-nent for estuarine wetlands. As presented inthis guidebook, Oregon’s rapid method fortidal wetlands has some structural similari-ties to CRAM and similarly was calibratedusing a large reference set of field data. Itdiffers from CRAM partly in that it explicitlyassesses individual functions as well aswetland condition, and uses a more diversearray of indicators in order to enhance itssensitivity to differences among individualwetlands. Also, the Oregon Watershed

Enhancement Board, in concert with theOregon Department of Land Conservationand Development, has recently supportedrevision of parts of the Oregon WatershedAssessment Manual that deal with estuariesand tidal wetland restoration (Brophy 2005).That document provides a field-based ap-proach for identifying (but not assessingfunctions of) wetlands that formerly weretidal and which might have potential forrestoration of their tidal circulation. It useslandscape-scale tools to provide broadguidance for estuary-wide decision making,integrating concepts of biogeography, land-scape ecology, and land use history to focuson historical and current connectivity be-tween tidal flows, wetlands, and streamnetworks.

Introduction

__________________________________1 “Tier 1” involves measurement at broad spatial scales, e.g., use of GIS to describe wetland distribution at a watershedscale. “Tier 2” involves design, testing, and application of methods for rapidly estimating wetland condition andfunctions at a site-specific scale. “Tier 3” involves detailed, direct measurements of wetland processes and structure,e.g., sampling of wetland invertebrates.


for Selected Tidal Wetlands of the OregonCoast Excel™ spreadsheet. The spreadsheetautomatically calculates scores for individualfunctions and other attributes. Data entrynormally takes no more than one hour perwetland. Using the method is straightfor-ward:

A variety of equipment was used to access andsurvey the 120 tidal marshes.

2 The HGM Rapid Assessment Method

This method uses separate data forms toassess functions, values, and risks to wetlandintegrity. Begin by copying the data forms(Appendix A1; use Appendix A2 only if youwish to assess values as well). After fillingthese out while visiting a wetland, you mustenter the data in the Software and Database

Method

How to Use the HGM Rapid Assessment Method

In brief, this method has three sequential components—1) recording field observations on standardized data sheets (offered in Appendix A1)2) entering the calculated numeric scores (with a measure of relative certainty) into a specially

designed Excel™ spreadsheet3) employing the spreadsheet to derive numbers that represent the relative level of function of the

wetland assessed


1. Confirm wetland status. First, be surethe site you’re assessing currently meetsfederal and state technical criteria forbeing a wetland at this time. Also besure the wetland you’re assessing is atidal wetland. That is, most of the sitemust be flooded by tides (either fresh orsaltwater) at least once a year and mustmeet jurisdictional criteria for being awetland.

2. Delimit the site. Delimit the “assess-ment unit‡” (wetland site) boundariesfollowing the guidance in Classifying theWetland, below. In some instances theseboundaries may be more restricted thanboundaries determined as part of aregulatory wetland delineation.

3. Gather existing information. Assembleexisting information most relevant to thewetland site. This may include—

• map of the site’s location in the con-text of its estuary

• polygon boundaries of the wetland asshown in the accompanying DVD oron National Wetlands Inventory (NWI)map server: http://wetlandsfws.er.usgs.gov/NWI/index.html

• county soil survey maps (available atNRCS offices, libraries, and online at:www.or.nrcs.usda.gov/pnw_soil/or_data.html)

• aerial photographs (available at officesof some state and federal resourceagencies, university libraries, andfrom private vendors)

• discussions with local residents andresource agency staff

• data from other investigators andresource agencies

4. Visit the site. Visit the site at least oncefor a 6-hour period. If you can visit itonly once and have flexibility in schedul-ing a date, visit it on or near the day ofthe month when high tides are highest(spring tide‡). During the visit, observeconditions described on the field forms.Walk as much of the site as is necessary

to make the specified observations withreasonable certainty. If one repeat visit isfeasible, schedule it for the month’slowest tide. If a third visit is possible butnot urgent, schedule it for the highest tideof the year. Assessment by amultidisciplinary team is encouraged butnot required. Prior training in the use ofthis method also is encouraged but notrequired at this time. For such scheduledtraining, contact the Department of StateLands or check on the Internet at: http://epp.esr.pdx.edu/calendar.html.

5. Fill out the data sheets. While in thefield, use your observations and bestjudgment to fill out the forms completely,e.g., putting an appropriate number inevery box marked “score” and “cer-tainty.” Be sure to read any explanatorynotes in the last column of each form,and refer to the Glossary (Appendix D) ifnecessary. Supplement your field obser-vations using the resources in #3 asnecessary. If you decide to assess thefunction called “Maintain Natural Bo-tanical Conditions,” be sure to followthe protocol described in “Protocol forassessing botanical indicators shown onData Form A2” (below) and Figure 3(page 11).

6. Transfer data to Excel™. Transfer thedata from your field forms to matchingparts of the Excel™ spreadsheet(TidalWet_Assess.xls) contained on theCD. For the most recent version of thespreadsheet and this guidebook, visit:www.oregonstate.edu/~adamusp/HGMtidal .

8. Print the results. After all data havebeen entered, print the resulting scoresfor the site’s functions, values, and/orecological risk. These were calculatedautomatically by the Excel™ program. Ifyou prefer not to use the spreadsheet, youmay calculate some of the summaryscores using a pocket calculator, insertingdata from your field forms into theformulas (scoring models) shown in

Method


Appendix C, taking careful note of themathematical order of operations in eachformula. One exception is the function,“Maintain Natural Botanical Condi-tions,” which must be calculated usingthe spreadsheet.

9. Interpret the results. Interpret theresults, partly by comparing your scoreswith those for other Oregon tidal wet-lands of the same subclass (shown inPart 2).

10. Annotate the results. Write a short sitedescription as an addition to your sitedata sheets, discussing any unusualconditions present at the time of yourvisit. Note other factors important tofunctions that might not be apparentfrom the scores generated by this rapidassessment method. Describe in wordsthe Values component of the assessment,if you chose to do that as well. Note thatthe Values assessment does not havescoring models associated with it.

Protocol for assessing botanical indicators shown on Data Form A2.

Dozens of protocols have been proposed for surveying vegetation, and the choice of any par-ticular one will depend on the objectives of the project. The following protocol features square-meter quadrats‡ placed along marsh transects. It is intended for use specifically for the objec-tives of this guidebook, and is required so data from future assessments using this guidebook’smethod may be compared with reference data that were collected using the same protocolduring guidebook development. If possible, vegetation data should be collected sometimeduring May–August.

1. In most instances, establish two parallel transects per wetland (Figure 3). One end of eachtransect should be at a point containing wetland vegetation that is nearest the adjoiningunvegetated bay or river; the other end should be at the approximate upper annual limit of tidalinundation (i.e., “upland”), as usually indicated by the tree line or driftwood line. If the wetlandoccupies all of an island with no upland, extend each transect the width of the island (if fea-sible). Transects should be relatively straight, but precise alignment is not essential.

2. Situate the two transects near the widest part of the wetland. Situate them to minimize oravoid crossing major channels and non-wetland spots (dikes, fills) within the wetland. Avoidplacing the transects within 2m of each other; much wider spacing (at least 10m) is preferred iflogistically possible. Do not try to “aim” the transects to intercept particular plant communitiesor attempt to make the transects “representative” of the wetland. Random placement, whiledesirable statistically, often presents logistical headaches and is relatively meaningless given thelimited replication (of only two transects).

3. In exactly 20 quadrats (square plots), each 1m x 1m, identify and estimate relative coverage(by percent) of each plant species. Each of the two transects should contain 10 quadrats,spaced equidistantly along the transect beginning at the vegetated transition from unvegetatedbay/river. However, if it becomes evident that less than 20% of a quadrat is vegetated, move tothe left or right of the transect until a spot is found where this criterion is met. (The botanicalprotocol in this guidebook is not intended to assess extent of unvegetated area in a wetland; thatis addressed only by indicator #28.)

4. In narrow marshes, the use of only two short transects could result in quadrats along eachtransect being closer than 2m to each other. To avoid this, deploy additional transects perpen-dicular to the bay or river until at least the 2m spacing is established between quadrats as wellas between transects. In rare instances, it may also be necessary to change transect orientationfrom perpendicular to oblique.

Method


Classifying the Wetland

The national guidebook for HGMassessment of tidal fringe wetlands(Shafer & Yozzo 1998) does notdefine any subclasses of the nationaltidal fringe class, nor does its regionalversion for the Gulf of Mexico (Shaferet al. 2002). Nonetheless, this Oregonguidebook recognizes threehydrogeomorphic subclasses of tidalfringe wetlands—

• Marine-sourced Low Marsh,sometimes called simply “lowmarsh”

• Marine-sourced High Marsh‡,sometimes called simply “highmarsh”

• River-sourced Tidal Wetland

These are defined using the key below. Formost purposes, tidal wetlands should beassigned to an HGM subclass based on theirpresent condition, not what is documented,believed, or imagined to have existed histori-cally. The classification of each Oregon tidalwetland polygon with regard to these threesubclasses is labeled provisionally on thedigital maps accompanying this document.However, the maps provide only a coarserendition of subclass boundaries and werenot comprehensively field-verified.

This guide may be used for assessing bothherbaceous (emergent marsh) and wooded(scrub-shrub, forested) tidal wetlands. How-ever, note that throughout this guide, theterms “tidal marsh” and “tidal wetland” areused interchangeably to denote both herba-ceous and wooded tidal wetlands; thoseterms do not include tidal aquatic-bed wet-lands, such as eelgrass beds (habitats thataren’t covered by this guide). Also note thatthe nouns “variable” and “indicator” are usedinterchangeably.

Method

Portions of wetlands flooded at least once annually byspring high tides are considered tidal wetlands in thisguidebook.

In summary, this method allows you to quickly assign an HGM subclassto many, but not all, tidal wetlands. Although it is impossible to assign aparticular wetland to a specific tidal fringe subclass quickly and un-equivocally, this method is expected to be flexible enough to accommo-date this uncertainty. Assigning a tidal wetland a priori to one of thethree HGM tidal fringe subclasses is not required by this method, butattempting to do so will help clarify your understanding of the wetlandand its functions.


1. Tidal forces cause the wetland to be flooded with surface water at least once annually, duringmost years. Excluded are wetlands whose water level or soil saturation may be influenced by tidalfluctuations but which lack a regular (at least annual) surface connection to tidal waters. Plantspecies that typically characterize upland habitats are absent or nearly so, and some wetland speciesthat are present may be characteristically tolerant of brackish as well as fresh salinity conditions.Channels, if present, are often narrow, winding, or branched, and may be deeply incised as a resultof tidal action. Regardless of the wetland’s salinity, it is located downriver from the recognizedhead-of-tide2 of its associated estuary. Drift logs and growth of trees‡ and moss often mark theupper boundary of annual flooding, particularly in the transition to non-tidal wetland or upland.

YES: Estuarine Fringe Wetland HGM Class; go to #2.NO: Other wetland classes; this guidebook is not applicable.

2. Tidal forces cause the wetland to be flooded at least once annually with saline or brackish surfacewater originating partly or wholly from the ocean. Often located within or along the fringes of amajor estuarine embayment or a slough off the embayment. Typically located within zones classi-fied as “Marine” or “Brackish” on maps published by Hamilton (1984), the National EstuarineInventory (1985, NOAA 1985; http://spo.nos.noaa.gov/projects/cads), and/or as “Estuarine” onNational Wetlands Inventory maps (http://wetlandsfws.er.usgs.gov/NWI/index.html). The wetlandand/or its immediate receiving waters may have one or more of the following indicators suggestiveof marine water: barnacles, seaweed wrack‡, salt marsh‡ plant species (halophytes such asSalicornia, Triglochin, Distichlis, Plantago maritima), springtide‡ minimum salinities of >5 ppt, ora preponderance (in adjacent flats) of rounded sediment particles indicative of marine-derivedsediments.

YES: Marine-sourced Fringe Wetland; go to #3.NO: River-sourced Tidal Fringe Wetland (RS).

3. All of the wetland is inundated at high tide‡ at least once during the majority of days during eachmonth of the year. This may be indicated by a combination of direct observation of tidal inunda-tion, predominance‡ of plant species characteristic of “low marsh” marine environments in Oregon,absence of woody plants, and/or by reference to data on local tidal range‡ paired with precise mea-surements of elevation and tidal fluctuations relative to an established geodetic benchmark. Lessdefinitively, a boundary between low and high marsh may be evidenced by a vertical break in themarsh surface or by accumulations of fresh wrack [seaweed, plant litter].

YES: Marine-sourced Low Tidal Fringe Wetland (MSL)‡, commonly called “low marsh.”NO: Marine-sourced High Tidal Fringe Wetland (MSH)‡, commonly called “high marsh.”

Method

Dichotomous Key to subclasses of tidal wetlands of the Oregon Coast

____________________________________________________________2 Locations of major heads of tide are shown on the accompanying DVD, or are available from the Department ofState Lands.

1

23

19August 2006 – Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 Method

Marine-sourced low and high marshes on sandy substrates often have assemblages of plant speciesthat differ from those in finer-substrate marshes.

Marine-sourced high marshes, like thesepictures, usually have greater richness ofplant species than marine-sourced lowmarshes.


The area assessed is termed the “assessmentunit” (or “wetland site”). Normally youshould sketch at least a rough version of theassessment unit on a map oraerial photograph before you visitthe site. For larger wetlands,marking of “waypoints” alongwetland boundaries using ahandheld GPS can expeditemapping and improve its accu-racy. For purposes of using thismethod, it is not necessary todelineate the wetland boundarywith the high level of precisioncustomary for jurisdictionaldeterminations.

Where you draw the boundariesof the assessment unit(s) willinfluence the resulting scores.When assessing activities thataffect only part of a wetland,you may assess and score sepa-rately at least two spatial units.In all cases, one of the units youassess must be the entire tidal wetland. Thisshould include both low and high marsh(when both are present), as well as internaltidal channels‡; it should never include anyadjoining non-tidal marsh. The other spatialunit, if desired, may be either (a) the portionof the wetland where construction or vegeta-tion management has been proposed, or (b)spatial units within the wetland based ontheir functionally-distinct HGM subclass(e.g., high vs. low marsh). Using the latter(subclass-based units) may be particularlyhelpful if one of those subclasses comprisesmore than 20% of the total wetland polygon.However, be aware that results for (a) and (b)are likely to be less accurate than for the firsttype of assessment unit because the first typemethod was based on data collected inwhole-wetland units.

The “default” boundaries you use for assess-ing the entire wetland should be the poly-gon boundaries of that wetland shown in the

accompanying DVD. However, adjoining ornearly-adjoining polygons should be consid-ered distinct wetlands whenever appearing tobe separated from each other by––

• a road or dike (even if it containsbridges, culverts, or tidegates), or

• upland, tideflat, rocky shore, orunvegetated water wider than about 100feet, or

• patches of salt-intolerant vegetationwider than 100 feet (e.g., dunegrass,freshwater marsh plants)

Boundaries of the entire assessment unitshould never be based solely on propertylines, fence lines, mapped soil series, vegeta-tion associations, elevation zones, or landuse designations.

Method

River-sourced tidal wetlands often occur as a narrow fringewith sharp transitions among vegetation assemblages.

Delimiting the Assessment Units


Usually the boundary between tidal marshand upland is clearly evidenced by a topo-graphic break, driftwood line, and/or shiftfrom predominantly‡ herbaceous to woodyvegetation. However, in the upper parts ofestuaries the spatial boundary between tidalwetlands (covered by this guidebook) andnon-tidal wetlands (not covered by thisguidebook) is often extremely difficult todelimit. Such identification relies uponbeing able to define a line between areasflooded more than once a year and thoseflooded less than once a year. When flood-ing appears to occur more than once annu-ally, you will need to determine whetherdaily tidal fluctuations had any role in thatflooding, either directly or by “backing up” ariver that otherwise flows unimpeded into its

estuary. Salinity alone cannot be used as acriterion, not only because of its extremetemporal variability, but also because manytidally-influenced wetlands register nosalinity, especially during times of peakflooding. Similarly, vegetation cannot beused alone because many woody plants (e.g.,

Sitka spruce, red alder) tolerate tidal floodingprovided salinity is not extreme. There areno salt-intolerant (freshwater) plants thatoccur only in tidal situations and wouldtherefore be useful indicators. Althoughdriftwood found in a riverine wetland mighthave been brought in by tides, it also couldhave been carried into the wetland solely byriver flooding.

The optional process for assigning bound-aries to subunits within the large wetlandpolygon can be equally challenging and issometimes arbitrary. If based on the tidalHGM subclasses, the boundaries will bedefined by the line between low marsh areas(inundated by tides at least once daily duringthe majority of the days in each month of the

year), and high marsh areas(flooded by tides less often).Often there is no clearseparation line and theseHGM subclasses are discon-tinuous within a wetland.That is, within a largerwetland polygon, “islands”or zones of high marsh orupland may be interspersedamid areas of extensive lowmarsh, and vice-versa. Inthe usual case, where nodata are available describingtidal frequency at variouspoints (elevations) within amarsh, subunits will need tobe based on prevailing plantspecies. If you’ve surveyedmarsh vegetation using theprotocol prescribed on page16 of this guidebook, the

determination of high vs. low marsh can bemade generally using the five indices calcu-lated by the spreadsheet accompanying thisguidebook: the species wetness index, andthe percent-cover and frequency indices forsalt-tolerant and salt-intolerant species.However, no thresholds have been deter-

Accumulations of driftwood along the edge between tidal wetlandsand uplands may mark the upland edge of the assessment unit;driftwood provides cover for small mammals and insects.

Method


mined for using these or other indices toclearly distinguish high marsh from lowmarsh. Such thresholds would undoubtedlybe influenced by factors such as substratetype and local climate. Uncommonly, visiblebreaks in marsh topography can provideclues for distinguishing high marsh from lowmarsh. Encrustations of sand or barnacleson older driftwood suggest marine origin andsupport the likelihood the wetland is marine-sourced.

Although the rapid method provided in thisguidebook can be applied at multiple scales(entire wetland, plus subunit within based onproposed activity or HGM subclass), thescores it yields are expected to be much moreaccurate for the entire wetland. That isbecause of the considerable subjectivityinvolved in defining boundaries of anysubunits and because field data used tocalibrate this method were collected at thescale of the entire wetland, not smallersubunits. Thus, this method is expected tobe less reliable when comparing high vs. low

marsh subunits within a marsh, or whencomparing different vegetation communitiesor development parcels within a marsh. Asnoted by authors of the HGM guidebook fortidal wetlands of the Gulf of Mexico (Shaferet al. 2002), “Since many of the modelvariables focus on geomorphological orlandscape characteristics, separation ofwetland subclasses based on elevation andsalinity did not seem justified.”

Nonetheless, this method is not blind toimportant distinctions between high and lowmarsh in scoring individual indicators ofmarsh function. Where supported by thefield data, scales for scoring the botanicalindicators took into account HGM subclassof the assessed unit. This was done by usingthe species wetness index and other indices(all presumed to indicate the HGM subclass)to statistically adjust the botanical scales.Likewise, the scoring scale for channel cross-sectional morphology took into account therelative location of the cross-section withinthe marsh.

Method


The first four data forms each have fourcolumns regarding each indicator––

1) identifier number and code for theindicator

2) description of the indicator with numericvalues

3) score boxes for the indicator and cer-tainty estimate, sometimes with interme-diate scale to translate raw numericvalues

4) guidance for interpreting the indicator

The fifth data form has three columns foreach value––

1) description of characteristics exemplify-ing the highest value of that function

2) your score

3) description of characteristics exemplify-ing the lowest value of that function

Method

Description of Data Forms

This method includes five data forms corre-sponding to its three major themes—

Data Form A1. Rapid Indicators ofRisks to Integrity and Sustainability ofTidal Wetlands

Data Form A2. Direct Indicators ofWetland Integrity That Require More-intensive Field Work

Data Form B1. Rapid Indicators ofFunction That May Be Estimated

Data Form B2. Rapid Indicators ofFunction Requiring Aerial Photographsor Measuring Equipment

Data Form C. Rapid Indicators of theValues of Functions

Data Form D. Vegetation Quadrat DataForm

The bottom of each row in the Guidance column contains abbreviations indicating the functions orother attribute that row’s indicator is associated with. The function codes are:

Function abbreviations

used in this document

description

Afish Maintain Habitat for Anadromous Fish

AProd Produce Aboveground Organic Matter

BotC Maintain Natural Botanical Conditions

Dux Maintain Habitat for Ducks and Geese

Inv Maintain Habitat for Native Invertebrates

LbirdM Maintain Habitat for Native Landbirds, Small Mammals, & Their Predators

Mfish Maintain Habitat for Visiting Marine Fish

NFW Maintain Habitat for Nekton-feeding Birds

RA Assessment of Risks to Wetland Integrity & Sustainability

Rfish Maintain Habitat for Other Visiting and Resident Fish

Sbird Maintain Habitat for Shorebirds

WI Wetland Integrity

WQ Maintain Element Cycling Rates and Pollutant Processing; Stabilize Sediment

Xpt Export Aboveground Plant & Animal Production


Brackets around these codes in the lastcolumn of data forms A1, A2, B1, B2 denotethat the indicator is not associated with thefunction directly, but is associated indirectlywith another function through which it isassessed. Part 2 of this guidebook definesand documents each of these functions, andgives the reasons each indicator in DataForms A1, A2, B1, and B2 was used, i.e.,documents its linkage to one or more func-tions.

Each indicator row has a box in which,optionally, you may enter a numeric estimate(as a decimal from 0 to 1) for scoring cer-tainty. Factors to consider when assigning acertainty score might include ones shown in“Considerations in assigning a certainlyscore to your site-specific assessment,”below. This guidance for scoring certainty isprovided to minimize the role of user person-ality, and maximize the consideration of

more objective factors, in scoring the cer-tainty for a specified indicator. The certaintyscores do not reflect overall scientific uncer-tainty underlying the use of each indicator,but rather the certainty of the user applyingthis method to a specific wetland site. Thecertainty scores should not be combinedmathematically with scores for functions,risk, condition, or value. The uncertaintyscores are intended to give an overall senseof the relative strength of the other reportedscores. They also should be used to helpprioritize collection of additional data asneeded to strengthen the results of a particu-lar assessment.

Method

Forested upland areas help protect tidal wetlands from extreme tempera-tures, erratic runoff regimes, and invasive plants.

25August 2006 – Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 Method

Considerations in assigning a certainty score to your site-specificassessment

consideration

low certainty ( = 0)

high certainty ( = 1.0)

How much of the site were you able to view?

little, from a distance all of the site, covering all of it on foot

How many visits were you able to make—and for how long?

one visit, less than 1 hour visits at 2+ seasons (high & low runoff), at monthly highest and lowest tides, 6 hours each

What is your experience & skill with this indicator?

minimal have been trained and/or have assessed many tidal wetlands

How observable is this indicator?

subjective, varies greatly in time, or nearly invisible (e.g., contamination)

objectively measurable (e.g., tributary lengths) or reliable measured data are available from other sources

26 Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 – August 2006Method

Tidal wetlands largely surrounded by develop-ment are often ditched or have atypical waterrunoff regimes.


3 Correctly Interpreting and Applying Results of this Method

Closed tidegate at low tide at a wetlandroad crossing.

The overarching goal of wetland assessmentis to determine the overall integrity andfunctions of specific wetlands. This HGMRapid Assessment Method quantifies indica-tors of wetland funtions that are intended tobe used in conjunction with expert judge-ment and other factors (noted below). Withcare, these specific numerical values can beused to better track or predict changes overtime in a specific wetland (such as inscoping restoration or mitigation alterna-tives) or to quantitatively compare specificfeatures of similar wetlands.

In some situations, the functions may beused to identify specific wetland characteris-tics to be highgraded in efforts to manage orrestore the wetland. Such action should beundertaken with great caution, however:among other considerations, it should in-volve suites of functions since the functionsused here are representative and becausefunctions work together in ways that are notwell understood.

Guidance

This guidebook’s HGM-based method doesnot change any current procedures for deter-mining jurisdictional status of wetlands: themethod is intended mainly for assessing thefunctions and values of individual wetlandsafter jurisdictional status has been deter-mined. Application of this method to wet-lands is not (at time of publication) requiredby law or policy. Contact the Oregon Depart-ment of State Lands and U.S. Army Corps ofEngineers for current regulatory require-ments. Although this method is sensitive todifferences among different subclasses oftidal wetlands, it does not allow users tocompare different tidal wetland subclassesdirectly (e.g., high vs. low marsh), norcompare non-tidal wetlands with tidal wet-lands (e.g., undiked vs. completely-dikedsites) or with any other habitat (e.g., tidaltideflats).

It must be recognized that scientific under-standing of wetlands is far less than optimalfor supporting the indicators and modelsused in methods such as the one in thisguidebook. That is equally the case with themost popular alternative: the application ofinformal “common sense” or “BPJ” (bestprofessional judgment). Moreover, standard-ized assessment methods are not immune toattempts by determined users to produce adesired result. Nonetheless, the potential forbiased manipulation of methods to achieve adesired result is not by itself a valid reasonfor failing to use formal methods in wetlanddecision-making. Less formal, non-stan-dardized methods are equally or more sus-ceptible to manipulation of results, andmanipulation may be less transparent. If biasis suspected, additional documentation and/or an independent assessment should berequired.

Interpreting Results


The consistency of results produced by thismethod among various independent users–with various levels of expertise, local knowl-edge, and training–has not been tested.Although every effort has been made in theselection and wording of indicators to createa rapid method that should provide accept-ably consistent results among unbiased users,all methods that rely on casual observation ofnonparametric indicators, rather than directmeasurement of natural phenomena, tend tobe imprecise. (In other words, while we didour best to pick sound indicators, anythingeasy to measure will likely not be veryprecise.) There exists no widely acceptedstandard of “adequate” consistency, and thisshould depend partly on the applicationobjective. Perhaps this issue is better statedas: “Is a new method more consistent andaccountable than the current method?”–thecurrent method often being solely the appli-cation of unstandardized personal judgmentsby diverse specialists.

The function indicators and scoring modelspresented in this guidebook are based on theauthor’s experience and interpretation ofscientific literature, as well as on the opin-ions of experts who attended DSL-sponsoredworkshops during development of themethod. The models (largely constructed ofindependent variables) do not measure actualprocesses or describe the statistical probabil-ity of a function occurring. They are notdeterministic equations, dynamic simulationmodels, statistical probability models, orother mathematical representations of pro-cesses taking place. The scoring models arenumeric representations of systematic quali-tative constructs and are intended to assist aspecific decision-making context. Thus, thescoring models are conceptually quite similarto models economists use to illustrate theeconomy that are based on leading economicindicators.

As is true of all other rapid assessmentmethods applicable to this region, thisguidebook’s scoring models and their indica-tors have not been validated. The time andcost of making the measurements necessaryto fully determine the model’s accuracywould be exorbitant. Nonetheless, the lackof indicator validation, as well as uncertaintyregarding repeatability of results, are not bythemselves sufficient reasons to avoid usingthis method; the alternative–relying entirelyon unstructured judgments of wetland tech-nicians–is not demonstrably better. Whenproperly applied, the models and their indi-cators are believed to adequately describerelative levels of function among sites, aswell as make some wetland decision-makingprocesses more standardized, accountable,and technically complete. Results of anyfuture scientific studies of functions of theregion’s tidal wetlands should be reviewedcarefully and often for ideas for indicatorsthat may improve upon ones now used.

It is recognized that this guidebook’s methodwill often need to be used at seasons or timesof day when conditions are less than ideal forthe required observations. Moreover, it isrecognized that the “snapshot” kind ofportrayal of a site obtained during a singlevisit is unlikely to adequately assess thelong-term natural disturbance regimes thatensure the viability of many sites and theirfunctions. Many indicators change to somedegree depending on the time of day, month,and year. These temporal changes poten-tially confound the interpretation of datafrom multiple sites visited at different times,and ultimately complicate the use of the datafor describing reference standard conditions.Indicators that describe plant species compo-sition and percent cover are especially likelyto vary within the sampling window (Junethrough September), and indicators such assalinity will vary greatly within a site duringa tidal cycle.



Formerly diked wetlands whose tidal circulation isrestored often pond water for longer periods each tidalcycle because their substrate has subsided to a lowerelevation.

Some indicators tend to correlatestrongly with the size of the marsh.Because function indices that use theseindicators may later be multiplied bymarsh area, the correlation of theseindicators with marsh area needs to be“factored out” or marsh area will implic-itly be double-counted. We have at-tempted to accomplish this by applyingparticular statistical procedures to thedata, and reflecting this in the manner inwhich the rapid method is configured inthe spreadsheet and in this document.These adjustment procedures and theirapplications are described further in Part2 (Science Review and Data AnalysisResults for Tidal Wetlands of the Or-egon Coast).

As noted elsewhere, the number of functionsthat wetlands perform far exceeds thosedescribed in this guidebook (see Adamus2001b for further discussion of this), so theguidebook focuses on a few that are easiestto assess in the short time periods requiredby the wetland permitting process.

The numeric scores should not be used alonewith expert judgment because the scoresreflect only a subset of factors vital todecisions about wetlands. In addition toexpert judgment and the functions andvalues from this method, factors that must beweighed in many wetland decisions, butwhich are addressed only partly or not at allby this method, include—

• availability of alternatives for the pro-posed development (potential for impactavoidance)

• availability and cost of appropriatenearby sites for compensatory mitigation

• intrinsic sensitivity of the site to naturaland human-related disturbance

• cost of any measures required to main-tain a wetland over time

• navigability of the site, or if the site isitself legally considered non-navigable,its perceptible influence on aquatic life(or other “uses” designated by the state)in nearby navigable waters

• relative contribution of the site’s floraand fauna to regional biodiversity

• special legal status of any of the site’sspecies

• actual or potential ability of the site toproduce timber, crops, fur, or othermarketable products

• recreational, open space, aesthetic, oreducational use of the site

• status of the site as a natural hazard area

• status of the site as a hazard or potentialhazard due to known accumulations ofchemical wastes

• existence of a conservation easement,deed restriction, local zoning designa-tion, or other legal instrument that limitsor allows particular uses of the site and/or its contributing watershed

• percent of total site acreage potentiallyaffected by a proposed alteration, andlocation of impacts within the site



• the magnitude of the proposed alteration,after accounting for the likely reliabilityof its impact minimization strategies

• technical “replaceability” or “manage-ability” of the site’s functions

• likelihood of compensatory mitigationbeing physically and biologically suc-cessful

• potential for the alteration to create apublic nuisance (directly, or through lossof wetland functions) either on-site or(especially) off-site

• potential for the alteration to imposeunreasonable burdens on local infrastruc-ture

• potential for cumulative impacts (e.g.,consideration of local loss rate of thissubclass of wetland)

• rules and policies of agencies involved inreviewing permit applications

Despite the limitations noted here,this method is believed to be one ofonly a few that expresses the bestavailable science in the format of asemi-quantitative rapid assessmentmethod. Draft versions of the methodwere reviewed by several wetlandscientists and were tested by manyusers. The method is the only rapidmethod applicable to Oregon thatdirectly incorporates reference datacollected from Oregon tidal marshes.It provides a structured means forconsidering many factors believedimportant to the condition and func-tions of tidal marshes, and can serveas a tool for educating resourcemanagers having limited experiencewith some tidal marsh functions.



Evaluating the HGM Method

The Oregon Department of State Landswelcomes feedback on how well the processand application of this HGM Rapid Assess-ment Method fulfills wetland managementneeds. Specific comments and input shouldbe directed to:

Janet Morlan, Wetlands Program ManagerOregon Department of State Lands775 Summer St. NE, Ste. 100Salem, OR 97301-1279phone: (503) 378-3805, ext. 236email: [email protected]


Scores generated by this method, as well asthe data from its accompanying referencedatabases, have several potential applicationsfor both regulatory and non-regulatoryprograms. The questions they can helpaddress include, but are not limited to—

• What effect might restoring or enhancingthe natural structure in a degraded marsh(by improving circulation, adding woodto its channels, etc.) have on the marsh’sfunctions?

• Which of several tidal marshes has likelysuffered the most degradation of itsfunctions, and therefore might benefit themost from restoration or enhancement?

• Which of several tidal marshes has likelysuffered the least degradation of itsfunctions, and therefore might be the bestchoice for conservation or to use as areference site?

• Should a permit application for alterationof a tidal marsh be denied altogether, orwill a proposed tidal marsh mitigationproject located elsewhere adequatelycompensate for loss of its functions?

• What is a realistic “target” orperformance standard for plant speciesrichness in a restored low marsh onsandy substrate on the outer coast?

• To inform the design of a tidal channelbeing created as part of a marshrestoration project, what channeldimensions have been found to be typicalof natural marshes in similar situationson the Oregon Coast?

• What proportion of the tidal marshes in aparticular watershed or estuary is at highrisk of long-term degradation?

• In terms of capacity to perform each ofthe 12 identified functions, how does thistidal marsh rank when compared with120 others that were already sampled onthe Oregon Coast?

• Over many years’ time, which functionsare probably increasing or decreasing asa result of structural changes made to agiven tidal marsh and its surroundings?

Agencies and consultants have already begunusing test versions of this method to examinesome of these questions.

Applying the Results of the HGM Method

32 Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 – August 2006Literature Cited

4 Literature Cited

Adamus, P.R. 1983. A Method for Wetland Functional Assessment. Vol. II. Methodology. Report No. FHWA-IP-82-24. Federal Highway Administration; Washington, D.C.

Adamus, P.R. 2001a. Guidebook for Hydrogeomorphic (HGM)–based Assessment of Oregon Wetland and RiparianSites. I. Willamette Valley Ecoregion, Riverine Impounding and Slope/Flat Subclasses. Volume IB: Technical Report.Oregon Division of State Lands; Salem, OR.

Adamus, P.R. 2001b. Guidebook for Hydrogeomorphic (HGM)–based Assessment of Oregon Wetland and RiparianSites. Statewide Classification and Profiles. Oregon Division of State Lands; Salem, OR.

Adamus, P.R. and D. Field. 2001. Guidebook for Hydrogeomorphic (HGM)–based Assessment of Oregon Wetlandand Riparian Sites. I. Willamette Valley Ecoregion, Riverine Impounding and Slope/Flat Subclasses. Volume IA:Assessment Methods. Oregon Division of State Lands; Salem, OR.

Brinson, M.M. 1993. A Hydrogeomorphic Classification of Wetlands. Tech. Rept. WRP-DE-4. US Army Corps ofEngineers Waterways Exp. Stn.; Vicksburg, MS.

Brophy, L. 2005. Estuary assessment. Oregon Watershed Assessment Manual. Oregon Watershed EnhancementBoard; Salem.

Collins, J.N., E. Stein, and M. Sutula. 2004. California Rapid Assessment Method for Wetlands. Report to theUSEPA, Region 9; San Francisco, CA.

Costanza, R., R. d’Arge, R. de Groot, S. Farber, M. Grasso, B. Hannon, K. Limburg., S.Naeem, R. O’Neill, J. Paruelo.,R. Raskin, P. Sutton, and M. van den Belt. 1997. The value of the world’s ecosystem services and natural capital.Nature 387:253-260.

Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats ofthe United States. U.S. Fish and Wildlife Service, Office of Biological Services, Biological Services Program FWS/OBS-79/31.

Giannico, G., and J. A. Souder. 2004a. The Effects of Tide Gates on Estuarine Habitats and Migratory Fish. SeaGrant Publication ORESU-G-04-002. COAS, Oregon State Univ.; Corvallis.

Giannico, G., and J. A. Souder. 2004b. Tide Gates in the Pacific Northwest: Operation, Types, and EnvironmentalEffects. Sea Grant Publication ORESU-T-05-001. COAS, Oregon State Univ.; Corvallis.

Good, J.W. 2000. Summary and current status of Oregon’s estuarine systems. pp. 33-44 in: Oregon State of theEnvironment 2000 Report. Oregon Progress Board; Salem.

Good, J.W. and C.B. Sawyer. 1998. Recommendations for a Non-regulatory Wetland Restoration Program forOregon. Oregon Sea Grant Publication No. ORESU-O-98-001. Oregon Sea Grant; Corvallis.

Hamilton, S.F. 1984. Estuarine Mitigation: The Oregon Process. Oregon Division of State Lands; Salem.

Hughes, R.M., S. Howlin, and P.R. Kaufmann. 2004. A biointegrity index for coldwater streams of western Oregonand Washington. Transactions of the American Fisheries Society 133:1497-1515.

33August 2006 – Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 Literature Cited

Hruby, T., K. Bruner, S. Cooke, K. Dublonica, R. Gersib, T. Granger, L. Reinelt, K. Richter, D. Sheldon, A. Wald, andF. Weinmann. 1999. Methods for Assessing Wetland Functions. Vol. I: Riverine and Depressional Wetlands in theLowlands of Western Washington. Ecology Publication 99-115. Washington Dept. of Ecology; Olympia, WA.

Mitchell, D.L. 1981. Salt marsh re-establishment following dike breaching on the Salmon River Estuary, Oregon.Thesis, Oregon State Univ.; Corvallis.

Morlan, J. 2000. Summary of current status and health of Oregon’s freshwater wetlands. pp. 45 – 52 In: OregonState of the Environment 2000 Report. Oregon Progress Board; Salem.

National Oceanic and Atmospheric Administration (NOAA). 1985. National Estuarine Inventory: Data Atlas,Volume 1: Physical and Hydrologic Characteristics. Rockville, MD: Strategic Assessment Branch, OceanAssessments Division. 103 pp.

National Research Council. 2001. Compensating for Wetland Losses Under the Clean Water Act. National AcademyPress; Washington, D.C.

Neckles, H.A., M. Dionne, D.M. Burdick, C.T Roman, R. Buchsbaum, and E. Hutchins. 2002. A monitoring protocolto assess tidal restoration of salt marshes on local and regional scales. Restor. Ecol. 10:556-563.

Seliskar, D.M. and J.L. Gallagher. 1983. The Ecology of Tidal Marshes of the Pacific Northwest Coast: A CommunityProfile. FWS/OBS-82/32. U.S. Fish and Wildlife Service; Washington, DC.

Shafer, D.J. and D.J. Yozzo. 1998. National Guidebook for Application of Hydrogeomorphic Assessment to TidalFringe Wetlands. Tech. Rep. WEP-DE-16. US Army Corps of Engineer Waterway Experiment Station; Vicksburg,MS.

Shafer, D.J., B. Herczeg, D. Moulton, A. Sipocz, K. Jaynes, L. Rozas, C. Onuf, and W. Miller. 2002. RegionalGuidebook for Application of Hydrogeomorphic Assessments to Northwest Gulf of Mexico Tidal Fringe Wetlands. USArmy Corps of Engineer Waterway Experiment Station; Vicksburg, MS.

Smith, R.D. 1993. A Conceptual Framework for Assessing the Functions of Wetlands. Tech. Rep. WRP-DE-3,Waterways Exp. Stn., US Army Corps of Engineers; Vicksburg, MS.

Smith, R. D. 2001. Hydrogeomorphic Approach to Assessing Wetland Functions: Guidelines for DevelopingRegional Guidebooks - Chapter 3, Developing a Reference Wetland System, ERDC/EL TR-01-29, U.S. Army EngineerResearch and Development Center; Vicksburg, MS.

Smith, R.D., A. Ammann, C. Bartoldus, and M.M. Brinson. 1995. An Approach for Assessing Wetland FunctionsUsing Hydrogeomorphic Classification, Reference Wetlands, and Functional Indices. Tech. Rept. WRP-DE-9,Waterways Exp. Stn., US Army Corps of Engineers; Vicksburg, MS.

Smith, R. D. and Wakeley, J. S. 2001. Hydrogeomorphic Approach to Assessing Wetland Functions: Guidelines forDeveloping Regional Guidebooks - Chapter 4, Developing Assessment Models, ERDC/EL TR-01-30, U.S. ArmyEngineer Research and Development Center; Vicksburg, MS.

Teal, J.M. 1962. Energy flow of a salt marsh ecosystem of Georgia. Ecology 43:614-624.

Thom, R.M. 1992. Accretion rates of low intertidal salt marshes in the Pacific Northwest. Wetlands 12:147-156.

Zedler, J.B. and R. Lindig-Cisneros. 2000. Functional equivalency of restored and natural salt marshes. pp. 569-582in: M.P.Weinstein and D.A. Kreeger (eds.). Concepts and Controversies in Tidal Marsh Ecology. Kluwer AcademicPublishers; Boston.


Data F

orm

A1. R

apid

Ind

icators o

f Risks to

Tidal W

etland

Integ

rity and

Su

stainab

ility

Ap

pen

dix A

. Data F

orm

s

This form

primarily assesses “stressors,” indicators of the risk a tidal w

etland may face from

various types of degradation usu ally associatedw

ith human activities. T

hese stressors have the potential in some situations to dim

inish wetland integrity. Specifically, they can reduce the

ability of a wetland to m

aintain a balanced, integrated, adaptive comm

unity of organisms w

ith a species composition, diversity, and func-

tional organization that compares w

ell to unaltered habitat of the Oregon C

oast. A w

etland may be considered to have high integrity w

hen allof its characteristic processes and parts are intact and functioning w

ithin their natural ranges of variation. After entering the appropriate

score in each box of this field form, enter your scores into the accom

panying spreadsheet, assign weights to the indicators if desired, and

compute the score for R

isk. When assessing these stressors, do not take into account their potential for being reversed. T

he “sustainability”of w

etland sites is assumed to be low

est when they are at greatest risk. W

hen combined w

ith other information, risk assessm

ent s such as thisare useful not only for assessing w

etland integrity and function, but also for helping prioritize sites for restoration based on a site’s likelihoodof having been ecologically degraded. O

ther factors, such as the wetland’s intrinsic sensitivity, scarcity, geom

orphic resilie nce, and landow

nerships, should also be considered when prioritizing restoration.

©2006 H

GM

Guidebook

Ap

pen

dix A

Hydrogeom

orphic Assessm

ent Guidebook for T

idal Wetlands of the O

regon Coast, P

art 1 – August 2006

Appendix A

. Data F

orm A

1, Intro

.


Wet

lan

d S

ite

Nam

e: _

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

_

Dat

e:_

__

__

__

__

__

_

Tim

e B

egin

:__

__

__

__

T

ime

En

d:

__

__

__

_

Ass

esso

r: _

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

__

_

To

tal

Mar

sh T

ran

sect

Len

gth

(co

mb

ined

): _

__

__

__

m

Est

imat

ed P

osi

tio

n o

f th

e as

sess

ed u

nit

in

th

e es

tuar

y:

nea

r o

cean

(lo

wer

on

e-th

ird

): _

__

__

_

mid

: _

__

__

_

nea

r m

ajo

r h

ead

-of-

tid

e (u

pp

er o

ne-

thir

d):

__

__

__

E

stim

ated

HG

M a

reas

in t

he

asse

ssed

un

it:

Mar

ine-

sou

rced

Hig

h M

arsh

: _______%

M

arin

e-so

urc

ed L

ow M

arsh

: ______%

R

iver

-sou

rced

Tid

al W

etla

nd

: _

__

__

__

%

cod

e in

dic

ato

r sc

ale/

sco

re

gu

idan

ce

1.

Bu

ffA

lt

Rel

ativ

e bu

ffer

bet

wee

n th

e w

etla

nd a

nd u

plan

d ar

eas.

C

alcu

late

: A

* (

B +

C).

[F

or

exam

ple

, fo

r A

, B

, C

bel

ow

, ca

lcula

te

2 x

(1 +

3)

= 8

.]

Scr

een t

he

resu

ltin

g c

alcu

lati

on w

ith t

he

scal

e on t

he

right

[ex:

8 =

0.3

], t

hen

ente

r th

e sc

ore

in t

he

box.

O

pti

onal

ly,

also

ente

r an

est

imat

e of

cert

ainty

(0 t

o 1

).

A)

Wit

hin

100

ft

of

the

wet

land

’s e

dg

e w

ith

ad

join

ing u

pla

nd

, th

e %

of

the

up

lan

d t

hat

con

tain

s p

avem

ent,

bu

ild

ing

s, o

r o

ther

bar

e su

bst

rate

:

% u

pla

nd

as

des

crib

ed

scal

e <

5 %

1

5-1

4 %

2

15 –

24

%

3 25-4

9 %

4

>50 %

5

wet

land o

ccupie

s nea

rly a

ll o

f an

isl

and,

and

non

e of

the

isla

nd i

s d

evel

op

ed

0

B)

Wit

hin

100 f

t of

the

wet

land’s

edg

e, t

he

pre

dom

inan

t el

evat

ion o

f th

e port

ion o

f th

e upla

nd t

hat

is

mo

st-d

istu

rbed

(p

aved

, la

nd

scap

ed, o

ver

gra

zed

, o

r b

are)

:

p

red

om

inan

t el

evat

ion

sc

ale

< 2

0 f

t h

igh

er t

han

wet

lan

d

1 20-5

0 f

t hig

her

2

>5

0 f

t h

igh

er

3 C

) W

ith

in 1

00

ft

of

the

wet

land

’s e

dg

e, t

he

sub

stra

te p

red

om

inat

ing

in t

he

po

rtio

n o

f th

e u

pla

nd t

hat

is

mo

st-d

istu

rbed

(p

aved

, la

nd

scap

ed, o

ver

gra

zed

, o

r b

are)

:

pre

do

min

ant

sub

stra

te

scal

e lo

am,

silt

, cl

ay

1 fi

ne,

san

dy s

oil

2

coar

se s

and (

min

imal

org

anin

lay

er),

fil

l, p

avem

ent,

or

rock

3

Scr

een t

he

resu

ltin

g c

alcu

lati

on w

ith

the

scal

e on t

he

right,

then

in

th

e box e

nte

r th

e sc

ore

and

opti

onal

ly a

n e

stim

ate

of

cert

ainty

(0 t

o 1

).

0

= 0

.01

1-2

= 0

.1

3

-6 =

0.2

7-9

= 0

.3

10

-12

= 0

.4

13

-15

= 0

.5

16

-18

= 0

.6

19

-21

= 0

.7

22

-24

= 0

.8

25

-27

= 0

.9

>

27

= 1

.0

sc

ore

#1:

ce

rtai

nty

#1:

With

in 1

00 ft

= t

he

per

cen

t w

ith

in t

he

enti

re a

rea

that

is

up

land a

nd w

ithin

1

00

ft.

of

the

wet

lan

d-u

pla

nd

ed

ge.

D

o n

ot

incl

ude

the

tidal

wet

land

itse

lf,

but

non-t

idal

wet

lands

may

be

incl

ud

ed a

s p

art

of

that

zo

ne.

M

easu

re t

he

100 f

t hori

zonta

lly f

rom

th

e w

etla

nd’s

upper

lim

it o

f an

nual

ti

dal

flo

odin

g (

hig

hes

t ti

de)

.

Exte

nd t

he

100 f

t li

mit

to 3

00 f

t if

a

per

enn

ial

fres

hw

ater

tri

bu

tary

flo

ws

thro

ugh t

he

wet

land,

i.e.

, 100 f

t on

eith

er s

ide

of

the

trib

uta

ry c

han

nel

, up

to 3

00 f

t aw

ay.

Use

d f

or:

R

A.*

*

see

pag

e 2

3 o

r A

pp

end

ix A

fo

r ab

bre

via

tio

ns

sco

re #

1:

cert

ain

ty #

1:

©20

06 H

GM

Gui

debo

okP

age

1/7

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m A

1


©2006 H

GM

GuidebookP

age 2/7H

ydrogeomorphic A

ssessment G

uidebook for Tidal W

etlands of the Oregon C

oast, Part 1 – A

ugust 2006A

ppendix A. D

ata Form

A1

cod

e in

dicato

r scale/sco

re g

uid

ance

2. C

hem

In

Max

imu

m risk

of th

e wetlan

d b

eing ex

posed

to chem

ical pollutants (exclu

din

g nutrients).

Calcu

late: T * (L

+ E

). [For ex

ample, 0

x (1

+ 1

) = 0

] where:

T T

oxic

ity scale

no p

ollu

tant so

urces lik

ely in

nearb

y ru

noff,

gro

undw

ater, or su

rface water; n

o h

istory

of recen

t sp

ills reachin

g th

e wetlan

d

0

som

e po

llutan

ts 1

L M

aximum

Lo

ad (of contam

inants) scale

diffu

se (distan

t sou

rce), or in

frequ

ent

( severe sto

rms o

nly

) 1

con

centrated

(nearb

y so

urce) o

r frequ

ent

2

E M

aximum

Exte

nt (of contam

inants) scale

limited

(only

a small %

of th

e wetlan

d is lik

ely

t o b

e exposed

to th

e chem

ical) 1

mo

st of w

etland

cou

ld b

e exp

osed

2

Com

pare th

e result w

ith th

e scale at the rig

ht to

determ

ine th

e score.

0

= 0

.01

2

= 0

.33

3

= 0

.66

4

= 1

.00

score #2:

certainty #2:

Toxicity = p

ollu

tants in

clude su

bstan

ces poten

tially h

armfu

l to

plan

ts or an

imals an

d p

resent w

ell above an

y n

atural

back

gro

und lev

el. Load

= ru

noff lo

ad o

f contam

inan

ts will d

epen

d p

artly o

n size,

slope, an

d so

il type o

f the co

ntrib

utin

g area; co

nsid

er annual

max

imu

m fo

r a no

rmal y

ear. E

xtent = “lim

ited” w

ould

apply

if surface w

ater travels o

nly

in

a single in

ternal ch

ann

el, or if th

e only

contam

inan

t source is

at a localized

spo

t alon

g th

e up

land

edg

e. “C

ertainty

” sho

uld

norm

ally b

e scored

very

low

for th

is in

dicato

r. If measu

red d

ata are availab

le, you m

ay u

se it to

info

rm co

mp

on

ents (T

) and

(L).

Used

for: R

A, In

v, A

fish, M

fish, R

fish, [N

FW

, Sb

ird,

Lbird

M].

3. N

utrIn

M

axim

um

risk o

f nutrient overload in

the w

etland

. C

alculate: S

* (L

+ E

) Fo

r exam

ple, 1

x (1

+ 2

) = 3

wh

ere:

S S

ou

rce

Typ

e scale

no

abn

orm

al sou

rces 0

min

or p

oten

tial or k

no

wn

sou

rce of n

itrog

en o

r p

ho

sphoru

s 1

majo

r po

tential o

r kn

ow

n so

urce o

f nitro

gen

or

pho

sphoru

s 2

L

Maxim

um L

oad (of nutrients)

scale

diffu

se or d

iluted

(distan

t sou

rce), or in

frequ

ent

1 co

ncen

trated (n

earby

sou

rce) or freq

uen

t 2

E

Maxim

um E

xte

nt

scale only

a small %

of th

e wetlan

d is lik

ely to

receive

inputs d

ue to

its relative elev

ation &

oth

er factors

1

no

t localized

2

Com

pare th

e result w

ith th

e scale at the rig

ht to

determ

ine th

e score.

0

= 0

.01

2

= 0

.33

3

= 0

.66

4

= 1

.00

score #3:

certainty #3:

Minor so

urce ty

pe =

wid

ely-scattered

ho

uses, law

ns, lo

w-

den

sity g

razing, p

arkin

g lo

ts, exten

sive stan

ds o

f alder,

recently

bu

rned

or lo

gg

ed areas, an

d/o

r occasio

nal larg

e boat

traffic. M

ajor source ty

pe =

neig

hborh

oods (n

ot o

n sew

er lines),

exten

sive co

ncen

trated g

razing

, waste treatm

ent p

lant efflu

ent,

man

y m

alfun

ction

ing

septic sy

stems, an

d/o

r bo

atyard

s, h

arbo

rs. Load

, Extent: see ab

ove.

If measu

red d

ata are availab

le, yo

u m

ay u

se it to in

form

co

mp

on

ents (S

) and

(E).

Used

for: R

A, A

Pro

d, D

ux, [W

Q, X

pt, In

v, A

fish, M

fish,

Rfish

, NF

W, S

bird

, Lbird

M].

score #3:

certainty #3:

score #2:

certainty #2:


©20

06 H

GM

Gui

debo

okP

age

3/7

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m A

1

cod

e in

dic

ato

r sc

ale/

sco

re

gu

idan

ce

4.

Sed

Sh

ed

Inco

min

g f

ine-

sed

imen

t o

verl

oad

.

As

a re

sult

of

hum

an a

ctiv

itie

s ou

tsid

e th

e w

etla

nd, se

dim

ent

load

s re

achin

g t

he

wet

lan

d a

re c

urr

entl

y (

sele

ct o

ne)

:

sed

imen

t lo

ads

sco

re

m0.

ost

ly n

orm

al f

or

the

wet

land’s

subcl

ass

and

loca

tio

n i

n t

he

estu

ary

01

so an0.

mew

hat

abov

e no

rmal

for

the

wet

land’s

subcl

ass

d l

oca

tion i

n t

he

estu

ary, due

to a

ccel

erat

ed e

rosi

on

up

slop

e, u

pri

ver

, o

r al

on

gsh

ore

50

m1.

uch

abov

e no

rmal

for

the

wet

land’s

subcl

ass

and

loca

tion i

n t

he

estu

ary, due

to a

ccel

erat

ed e

rosi

on

up

slop

e, u

pri

ver

, o

r al

on

gsh

ore

00

sc

ore

#4:

cert

ain

ty #

4:

Ignore

th

e w

etla

nd’s

abil

ity t

o t

rap w

hat

ever

sed

imen

t ar

riv

es—

con

sid

er o

nly

its

ex

po

sure

to

ele

vat

ed s

edim

ent

load

s.

Pote

nti

al s

ourc

es i

ncl

ud

e: e

rodin

g b

anks,

logged

or

burn

ed

area

s, m

inin

g (

espec

iall

y g

ravel

, pla

cer)

, ro

ads,

fre

quen

t d

red

gin

g,

liv

esto

ck, A

TV

s.

Co

nsi

der

pro

xim

ity

, ex

ten

t,

slope,

su

bst

rate

type,

an

d n

um

ber

of

yea

rs t

o r

ecover

. “N

orm

al”

for

a w

etla

nd n

ear

the

estu

ary m

outh

may

be

a g

reat

er l

oad

than

fo

r a

wet

lan

d n

ear

hea

d-o

f-ti

de,

bec

ause

lo

ad i

ncr

ease

s dow

nst

ream

even

in p

rist

ine

estu

arie

s.

Use

d f

or:

R

A, In

v,

[Afi

sh,

Mfi

sh,

Rfi

sh,

NF

W, S

bir

d,

Lbir

dM

].

5.

So

ilX

On

site

so

il d

istu

rban

ce.

How

mu

ch o

f th

e as

sess

men

t unit

(only

the

par

t th

at i

s st

ill

wet

land)

has

bee

n

affe

cted

by

on

go

ing

or

pas

t er

osi

on

/ co

mp

acti

on

cau

sed

dir

ectl

y b

y h

uman

ac

tivi

ties

.

no

ne

1- 1

0%

10-5

0%

>50%

o

ng

oin

g

0

2

3

4

his

tori

cal b

ut

still

ap

par

ent

0

1

2

3

Sel

ect

on

e n

um

ber

fro

m e

ach

ro

w. T

hen

su

m t

he

two

cho

sen

nu

mb

ers

and

ap

ply

th

e sc

ale

on t

he

right

to d

eriv

e th

e sc

ore

.

0

= 0

.01

1

= 0

.1

2 =

0.2

3

= 0

.3

4 =

0.4

5

= 0

.6

6 =

0.8

7

= 1

.0

sc

ore

#5:

ce

rtai

nty

#5:

Pote

nti

al d

istu

rban

ces

wit

hin

th

e w

etla

nd i

ncl

ude:

li

ves

tock

, A

TV

s, r

esto

rati

on a

ctiv

itie

s, s

ubsi

den

ce

asso

ciat

ed w

ith d

ikin

g, dit

ches

, fi

lls,

log s

tora

ge.

C

onsi

der

ex

tent

and s

ever

ity.

In

fer

pas

t lo

g s

tora

ge

fro

m h

isto

rica

l ae

rial

ph

oto

gra

ph

s,

loca

l co

nta

cts,

pre

sen

ce n

earb

y o

f old

pil

ings,

and

par

tial

ly-b

uri

ed c

ut

logs.

In

fer

lives

tock

fro

m p

rese

nce

of

fen

ces,

or

loca

l k

no

wle

dg

e.

Use

d f

or:

R

A, A

Pro

d, W

Q, [X

pt,

Inv, A

fish

, M

fish

, R

fish

, N

FW

, S

bir

d,

Lb

ird

M].

sco

re #

5:

cert

ain

ty #

5:

sco

re #

4:

cert

ain

ty #

4:


cod

e in

dicato

r sco

re g

uid

ance

6. D

ikeDry

Deg

ree the area th

at is still wetlan

d (an

d in

cludin

g its in

ternal ch

annels)

beco

mes drier (i.e., m

uted

tidal flo

odin

g) as a resu

lt of d

itches o

r the

installatio

n o

f dik

es, tideg

ates, culv

erts, and o

ther artificial co

nstrictio

ns.

score

no

such

alteration

s, and

no changes ob

served

0.01

floo

din

g fro

m tid

e or ru

no

ff occu

rs less often

as a resu

lt of th

e alterations—

noneth

eless, nearly

all areas w

ithin

the w

etland

that p

revio

usly

were

flooded

by d

aily tid

es continue to flood daily

0.33

som

e areas that p

revio

usly

were flo

od

ed b

y d

aily

tides o

r up

land ru

no

ff no longer flood daily, b

ut

are still tidal w

etland; d

urin

g m

onth

ly lo

w tid

es, th

ere is mu

ch less w

ater in th

e wetlan

d th

an

prev

iously

0.66

daily

tidal circulation has been eliminated

from

all b

ut a sm

all part o

f the w

etland

; severe red

uctio

n

in freq

uen

cy, d

uratio

n, an

d d

epth

of d

aily an

d

mo

nth

ly h

igh

/low

tide

1.00

Note: F

or m

any d

iked

wetlan

ds, th

e appro

priate sco

re will b

e 0.6

6.

sco

re #6:

certain

ty #6:

Wh

ere histo

rical data are lack

ing

, con

sider “d

rier” relativ

e to n

earby u

naltered

wetlan

ds o

f about th

e same

elevatio

n &

size. Wetlan

ds receiv

ing little u

plan

d ru

noff

or g

roundw

ater seepag

e are especially

vuln

erable to

this

conditio

n w

hen

they

are di k

ed. M

ainly

inclu

de

constrictio

ns w

ithin

or alo

ng th

e uplan

d o

r water ed

ge o

f th

e wetlan

d. In

rare instan

ces decreased

onsite flo

odin

g

may

be attrib

uted

to p

resence o

f up

river d

ams, w

ater d

iversio

ns, o

r dred

gin

g (d

ee pen

ing

) of estu

ary m

ou

ths.

Ignore d

ryin

g d

ue to

geo

log

ic uplift o

r to sed

imen

t-related

increases in

elevatio

n o

f marsh

surface, b

ut

inclu

de d

ryin

g if d

ue to

sedim

ent b

lock

age o

f surface

water in

pu

ts. As tim

e allow

s, use p

roced

ures d

escribed

b

y B

roph

y (2

00

5) fo

r locatin

g tid

egates.

Used

for: R

A.

7. D

ikeWet

Deg

ree this w

etland

and

/or its ch

ann

els beco

mes w

etter (mo

re po

nd

ing

) as a resu

lt of in

stallation o

f dik

es, tideg

ates, culv

erts, ditch

es, and o

ther artificial

constrictio

ns o

r excav

ations, in

cludin

g su

bstrate co

mp

action an

d su

bsid

ence

associated

with

these.

score

no

such

alteration

s, and

no changes ob

served

0.01

som

e areas with

in th

e wetlan

d n

ow

floo

d m

ore

often

, longer, o

r mo

re exten

sively

as a result o

f alteratio

ns, but only at m

onthly high (spring) tide an

d/o

r du

ring

heav

y p

recipitatio

n

0.33

som

e areas with

in th

e wetlan

d n

ow

flood m

ore

often

, lon

ger, o

r mo

re exten

sively

and this is noticeable each day

; and

/or u

plan

d ru

noff is

noticeab

ly im

pounded

with

in th

e wetlan

d at v

arious

times as a resu

lt of th

e alteration

s

0.66

mu

ch o

f the site rem

ains flooded long after daily

high tide; and

/or m

ajor in

crease in flo

od

ing as a

result o

f sedim

ent su

bsid

ence fo

llow

ing

dik

ing

1.00

Note: F

or m

any d

iked

wetlan

ds, th

e appro

priate sco

re will b

e 0.6

6.

sco

re #7:

certain

ty #7:

Do

no

t inclu

de d

ike b

reachi n

g o

r remo

val th

at mad

e the

site wetter (su

ch as th

at evid

enced

by d

ead trees).

Where h

istorical d

ata are lackin

g, co

nsid

er “wetter”

relative to

nearb

y u

naltered

wetlan

ds o

f about th

e same

elevatio

n. D

iked

wetlan

ds are esp

ecially v

uln

erable to

th

is con

ditio

n if th

ey h

ave p

erenn

ial tribu

taries, direct

storm

water in

pu

ts, or seep

s/wetlan

ds alo

ng th

eir uplan

d

edg

e. In rare in

stances in

creased o

nsite flo

od

ing

may

be

attributed

to in

creased ru

noff fro

m p

avem

ent, in

puts

from

offsite d

itches, o

r recent clearcu

tting in

the

watersh

ed. A

s time allo

ws, u

se pro

cedu

res describ

ed b

y

Bro

ph

y (2

005

) for lo

cating tid

egates.

Used

for: R

A.

score #6:

certainty #6:

score #7:

certainty #7:

©2006 H

GM

GuidebookP

age 4/7H

ydrogeomorphic A

ssessment G



oast, Part 1 – A

ugust 2006A

ppendix A. D

ata Form

A1


©20

06 H

GM

Gui

debo

okP

age

5/7

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m A

1

cod

e in

dic

ato

r sc

ore

g

uid

ance

8.

F

oo

tVis

E

xte

nt

and

fre

qu

ency

of

wet

land

vis

itat

ion.

C

alcu

late

: A

+ (

B*2)

+ (

C*3

). [F

or

exam

ple

, 10

+ (

20

x2

) +

(7

0x3

) =

260

] w

her

e:

__

__

_(A

) %

of

wet

lan

d &

up

land

* v

isit

ed o

nly

rare

ly (

<1

0 d

ays

/yr)

b

y p

eop

le o

n fo

ot

__

__

_(B

) %

of

wet

lan

d &

up

land

* w

ith

in

term

edia

te v

isit

atio

n f

req

uen

cy

__

__

_(C

) %

of

wet

lan

d &

up

land

* v

isit

ed d

aily

or

alm

ost

so (

>360 d

ays/

yr)

*

incl

ud

es u

pla

nd w

ith

in 1

00

ft.

th

e re

sult

ing

nu

mb

er

sco

re

<110

1 (

infr

equen

t &

lo

cali

zed v

isit

atio

n)

0.0

1

10-1

39

0.

33

140-

6 199

0.

62

00

+

0 (f

req

uen

t &

ex

ten

siv

e v

isit

atio

n)

1.0

sc

ore

#8:

ce

rtai

nty

#8:

A,

B,

and C

must

su

m t

o 1

00%

.

Ass

um

e an

av

erag

e v

isit

or

“cas

ts a

dis

turb

ance

sh

ado

w”

of

rad

ius

10

0 f

t.

Infe

r gre

ater

vis

itat

ion f

requen

cy i

f cl

ose

r to

ro

ads

& b

uil

din

gs

(esp

ecia

lly p

opula

tio

n

cen

ters

), p

ub

lic

lan

d,

most

ly h

igh

mar

sh,

and

/or

sig

ns

of

use

, e.

g., f

oo

t tr

ails

. U

sed

fo

r:

RA

, N

FW

, D

ux

, S

bir

d.

9.

Bo

ats

H

ow

fre

qu

ent

and

clo

se i

s bo

at t

raff

ic (

all

typ

es)?

<1

00 f

t aw

ay

100-

1000

ft

away

>1

000

ft

away

se

ldo

m (

<1

2x

/day

) 0

.6

0.4

0

.0fr

equ

ent

2

0

.8

0.6

0.

nea

rly

con

4

st

ant

1.0

0

.80

. S

elec

t th

e la

rges

t num

ber

that

is

appli

cable

and e

nte

r it

in t

he

Sco

re b

ox.

sc

ore

#9:

ce

rtai

nty

#9:

Use

d f

or:

R

A, N

FW

.

10.

Ho

meD

is

Pro

xim

ity (

ft)

to t

he

near

est

inha

bite

d st

ruct

ure.

pro

xim

ity

sco

re

<200’

1.00

2

00’-

999’

0.75

1

000

’-199

9’

0.50

2

000

’-500

0’

0.25

>

50

00

’ 0.

01

sc

ore

#10

:

ce

rtai

nty

#10

:

Est

imat

e th

e dis

tance

fro

m t

he

wet

land-u

pla

nd

edge

close

st t

o t

he

stru

cture

. T

he

stru

cture

m

ust

be:

(a

) in

hab

ited

fo

r at

lea

st 2

mo

nth

s p

er y

ear,

and

(b

) n

ot

con

tin

uo

usl

y s

epar

ated

fro

m w

etla

nd

by

w

ater

wid

er t

han

10 f

t.,

e.g., n

ot

on a

n o

pposi

te

shore

. A

eria

l photo

gra

ph

s or

topo m

aps

are

use

ful.

U

sed

fo

r:

RA

, L

bir

dM

.

sco

re #

10:

cert

ain

ty #

10:

sco

re #

9:

cert

ain

ty #

9:

sco

re #

8:

cert

ain

ty #

8:


cod

e in

dicato

r sco

re g

uid

ance

11. R

oad

X

Pro

xim

ity (ft) to

the n

earest paved area:

<10 ft 10-100’

100-1000’ p

rimar

1.

6

2

y road

s 0

0

.0

.seco

n3

0

.01

d

ary road

s 0

.6

0.

En

ter the m

axim

um

app

rop

riate nu

mb

er directly

into

the sco

re b

ox

to th

e righ

t.

sco

re #11:

certain

ty #11:

Co

nsid

er park

ing

lots (>

20

veh

icle capacity

) to b

e prim

ary

road

s. Prim

ary ro

ads u

sually

hav

e >1

veh

icles/min

ute d

urin

g

the d

aytim

e. If a prim

ary ro

ad b

ord

ers on

ly a tin

y fractio

n o

f a w

etland’s u

plan

d ed

ge, treat it as a seco

ndary

road

. U

sed fo

r: RA

, Lb

irdM

.

12. In

vas P

resence o

r poten

tial for invasive exotic invertebrates.

score

no in

vasiv

e exotic in

verteb

rates hav

e be

repo

rted fro

m th

is estuary

(see gu

idan

ce at rig

ht), an

d th

ere are no

oyster cu

ltivati

facilities or large-ship traffic ro

utes in

simil

parts o

f the sam

e estua efao

n

ar ry

01 n

r 0.

no in

vasiv

e exotic in

verteb

rates hav

e be

repo

rted fro

m th

is estuary

(see colu

mn

at frig

ht), b

ut th

ere are oyster cu

ltivatio

n faciliti

and/o

r large sh

ips traffic in

the estu

a eaes ry

50 n

r 0.

po

pu

lation

s of in

vasiv

e exo

tic inv

ertebrates a

know

n to

hav

e beco

me estab

lished

in th

estua

rry

00 e is

1.

sco

re #12:

certain

ty #12:

Green

crabs o

r oth

er inv

asive in

verteb

rate species h

ave b

een

do

cum

ented

in T

illamo

ok

, Netarts, S

almo

n, S

iletz, Yaq

uin

a, A

lsea, Um

pqua, C

oos, an

d C

oquille estu

aries. Oyster

facilities are presen

t in so

me o

f these p

lus in

the N

ehalem

an

d S

iuslaw

estuaries.

Large ship traffic = d

eep-d

raft vessels, esp

ecially th

ose th

at d

ischarg

e foreig

n b

allast water.

Used

for: R

A, In

v, [A

fish, M

fish, R

fish, N

FW

, Sb

ird,

Lbird

M].

score #12:

certainty #12:

score #11:

certainty #11:

©2006 H

GM

GuidebookP

age 6/7H

ydrogeomorphic A

ssessment G



oast, Part 1 – A

ugust 2006A

ppendix A. D

ata Form

A1


©20

06 H

GM

Gui

debo

okP

age

7/7

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m A

1

cod

e in

dic

ato

r sc

ale/

sco

re

gu

idan

ce

13.

Inst

abil

Po

ssib

le in

stab

ility

of

the

wet

lan

d.

Cal

cula

te t

he

foll

ow

ing u

sing t

he

num

eric

val

ues

bel

ow

: A

+ B

+ C

+ D

+ E

= s

cale

T

hen

use

the

scal

e to

the

right

and e

nte

r a

score

in t

he

box.

A)

Liv

ing

tree

s or

shr

ubs

> 1

0 f

t. t

all

and f

looded

by t

ide

at l

east

once

per

yea

r:

des

crip

tio

n

valu

e m

any

1 fe

w

2 n

on

e 3

B)

Per

cent

of

wet

land

tha

t is

hig

h m

arsh

(not

flooded

dai

ly d

uri

ng

mo

st o

f th

e m

onth

, but

stil

l fl

ooded

occ

asio

nal

ly b

y t

ide)

: d

escr

ipti

on

va

lue

>50%

0

10

-50

%

1 1

-10

%

2 <

1%

3

C)

Cha

nge

in a

rea

of

wet

land a

nd a

djo

inin

g t

idef

lat

as i

ndic

ated

fro

m

his

tori

cal

dat

a, m

aps,

or

imag

es:

des

crip

tio

n

valu

e in

cor

reas

e fr

om

sed

imen

tati

on

, no n

oti

ceab

le c

han

ge,

or

no d

ata

1

los

3 s

of

mar

sh a

rea

fro

m e

rosi

on

or

win

db

low

n s

and

(n

ot f

rom

fil

lin

g, dik

ing, dra

inag

e)

D)

Tid

al c

ircu

lati

on:

des

crip

tio

n

valu

e no

evi

denc

e ti

dal

flo

odin

g r

estr

icte

d d

uri

ng p

ast

100 y

ears

0

full

daily

tid

al f

loo

din

g r

esu

med

mor

e th

an 1

0 y

ears

ago

1 fu

ll da

ily t

idal

flo

od

ing

res

um

ed le

ss th

an 1

0 y

ears

ago

2 pa

rtia

l tid

al f

loo

din

g r

esu

med

mor

e th

an 1

0 y

ears

ago

3 pa

rtia

l tid

al f

loo

din

g r

esu

med

less

than

10

yea

rs a

go

4

E)

Pre

dom

inan

t su

bstr

ate:

d

escr

ipti

on

va

lue

loam

, si

lt,

clay

1

sandy s

oil

2

sand d

unes

, fi

ll,

dre

dged

mat

eria

l, r

ock

3

3

= 0

.01

4

= 0

.1

5

= 0

.2

6

= 0

.3

7

= 0

.4

8

= 0

.5

9

= 0

.6

1

0 =

0.7

11

= 0

.8

1

2 =

0.9

>

12 =

1.0

sco

re #

13:

ce

rtai

nty

#13

:

(C)

Do

no

t in

clu

de

dir

ect

loss

es f

rom

fil

lin

g o

r d

ikin

g,

or

incr

ease

s due

to r

esto

rati

on –

in

clude

only

those

fr

om

sed

imen

tati

on

or

ero

sio

n. I

f ar

ea l

oss

can

be

do

cum

ente

d a

t an

y t

ime

sin

ce 1

85

0,

assi

gn

a “

0”

regar

dle

ss o

f poss

ible

subse

quen

t in

crea

sed a

rea.

B

e ca

refu

l w

hen

co

mp

arin

g h

isto

rica

l m

aps

or

aeri

al

photo

gra

phs,

as

appar

ent

chan

ges

may

act

ual

ly b

e due

to d

iffe

rence

s in

the

dai

ly o

r m

onth

ly t

idal

cycl

e w

hen

th

e im

age

was

rec

ord

ed.

(D)

Res

tora

tio

n m

ay h

ave

bee

n i

nte

nti

on

al o

r fr

om

nat

ura

l er

osi

on o

f dik

es.

Par

tial

tid

al f

loodin

g

incl

udes

mar

shes

wit

h “

mute

d”

tidal

am

pli

tude

due

to

culv

ert

rest

rict

ion

s o

r m

od

ifie

d t

ideg

ates

. P

rese

nce

of

dik

e re

mn

ants

do

es n

ot

alw

ays

mea

n t

idal

flo

odin

g i

s p

arti

al.

U

sed

fo

r:

RA

, W

Q.

sco

re #

13:

cert

ain

ty #

13:


Data F

orm

A2. D

irect Ind

icators o

f Wetlan

d In

tegrity th

at Req

uire M

ore-In

tensive F

ield W

ork

If unable to perform these relatively intensive m

easurements, you m

ay skip this section and proceed with section B

1, but wetland integrity

and the botanical function will not be scored. To calculate inform

ation needed in this section, you must first enter your field data in the

accompanying E

xcel™ spreadsheet. For the plant indicators, you m

ust use the survey protocol specified in Protocol for assessing botani-

cal indicators on page 16.

©2006 H

GM

Guidebook

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm A

2, Intro

.


©20

06 H

GM

Gui

debo

okP

age

1/2

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m A

2

cod

e in

dic

ato

r sc

ore

g

uid

ance

14

. R

atio

C

Cha

nnel

pro

port

ions

. W

alk

up

stre

am t

o e

ach

of

fiv

e su

rvey

po

ints

alo

ng

a m

ajo

r in

tern

al c

han

nel

(se

e ri

ght

colu

mn

) an

d m

easu

re t

he

chan

nel

topw

idth

and in

cisi

on

dept

h. T

hen

in

pu

t th

e m

easu

rem

ents

on

th

e ac

com

pan

yin

g

spre

adsh

eet

(par

t A

2a)

and a

llow

it

to c

alcu

late

the

Ab

solu

te D

iffe

ren

ce (

mea

n).

C

om

par

e th

at n

um

ber

wit

h

the

left

sid

e of

the

foll

ow

ing s

cale

, to

det

erm

ine

the

score

.

Ente

r th

e sc

ore

in t

he

colu

mn

to t

he

right.

If

the

site

co

nta

ins

no t

idal

chan

nel

, sk

ip t

his

sec

tion.

Pro

toco

l:

The

five

surv

ey p

oin

ts (

Fig

ure

1)

should

be

arra

yed

fro

m w

her

e th

e m

ain c

han

nel

exit

s th

e w

etla

nd (

#1)

to t

he

mo

st d

ista

nt

but

connec

ted f

eeder

ch

annel

(#5),

and

sho

uld

be

rep

rese

nta

tiv

e o

f th

e o

ther

nea

rby

sec

tio

ns

of

chan

nel

. I

f n

o b

ank

s ar

e ap

par

ent,

th

en m

easu

re a

t th

e fi

rst

maj

or

bre

ak i

n t

he

chan

nel

sid

e sl

ope

(oft

en t

he

wet

ted

wid

th a

t h

igh

tid

e).

Veg

etat

ion

ch

ang

e ca

n a

lso

be

use

d t

o

dis

cern

th

e to

p o

f th

e b

ank

. M

easu

re t

o t

he

geo

mo

rph

ic

top

, no

t to

wh

ere

the

wat

er l

evel

is.

sc

ore

# 1

4:

ce

rtai

nty

# 1

4:

Topw

idth

= t

he

dis

tan

ce f

rom

ban

k-t

o-b

ank

. M

easu

re

to t

he

geo

mo

rph

ic t

op

, n

ot

to w

her

e th

e w

ater

lev

el i

s.

Inci

sion

dep

th =

the

ver

tica

l dis

tance

(m

) bet

wee

n t

he

chan

nel

bo

ttom

an

d t

he

top

of

a li

ne

run

nin

g b

etw

een

th

e ch

ann

el b

ank

s.

S

ee P

art

2 f

or

des

crip

tio

n o

f as

sum

pti

on

s b

ehin

d t

his

in

dic

ator

and i

ts s

cali

ng.

U

sed

fo

r: W

I, W

Q.

sco

re #

14:

cert

ain

ty #

14:


©2006 H

GM

GuidebookP

age 2/2H

ydrogeomorphic A

ssessment G



oast, Part 1 – A

ugust 2006A

ppendix A. D

ata Form

A2

cod

e g

uid

ance

15. Sp

PerQ

d 16. S

pD

eficit 17. A

llPC

90 18. D

om

Def

19. NN

20PC

20. N

Nd

ef 21. A

nn

Def

22. Tap

PC

def

23. Sto

lPC

def

24. Tu

ftPC

def

These b

otan

ical indicato

rs are calculated

and scaled

auto

matically

in p

art A2 o

f the acco

mp

any

ing

spread

sheet, u

sing

field d

ata you en

ter in

part A

2b

of th

e spread

sheet. Y

ou

mu

st first collect th

e data u

sing

the fo

llow

ing

pro

t oco

l. Reco

rd th

e plan

t data o

n th

e Ap

pen

dix

E

(Veg

etation Q

uad

rat Data F

orm

), then

transfer to

the sp

readsh

eet. 1

. In m

ost in

stances, estab

lish tw

o p

arallel transects p

er wetla n

d (F

igu

re 3), p

referably

som

etime b

etween

May

and

Sep

temb

er. On

e end o

f each

transect sh

ould

be at a p

oin

t contain

ing w

etland v

egetatio

n th

at is nearest th

e adjo

inin

g u

nv

egetated

bay

or riv

er; the o

ther en

d sh

ould

b

e at the ap

pro

xim

ate upp

er annu

al limit o

f tidal in

und

ation (i.e., “u

plan

d”), as u

sually

ind

icated b

y th

e tree line o

r driftw

ood lin

e. If the

wetlan

d o

ccupies all o

f an islan

d w

ith n

o u

plan

d, ex

tend

each tran

sect the w

idth

of th

e island (if feasib

le). Tran

sects should

be relativ

ely

straight, b

ut p

recise alignm

ent is n

ot essen

tial. 2. S

ituate th

e two tran

sects near th

e wid

est part o

f the w

etland. S

ituate th

em to

avoid

or m

inim

ize crossin

g o

f majo

r chan

nels an

d n

on-

wetlan

d sp

ots (d

ikes, fills) w

ithin

the w

etland

. Av

oid

placin

g th

e transects w

ithin

2m

of each

oth

er—m

uch

wid

er spacin

g (at least 1

0 m

) is preferred

if logistically

possib

le. Do n

ot try

to “aim

” the tran

sects to in

tercept p

articular p

lant co

mm

unities o

r attempt to

mak

e the tran

sects “rep

resentativ

e” of th

e wetlan

d. R

andom

placem

ent, w

hile d

esirable statistically

, often

pr esen

ts logistical h

eadach

es and is relativ

ely

mean

ingless g

iven

the lim

ited rep

lication (o

f only

two tran

sects). 3

. In ex

actly 2

0 q

uad

rats (squ

are plo

ts), each w

ith d

imen

sion

s 1m

x 1

m, id

entify

and

assess relative p

ercent-co

ver o

f each p

lant sp

ecies. E

ach o

f the 2

transects sh

ou

ld co

ntain

10 q

uad

rats, spaced

equid

istantly

along th

e transect b

egin

nin

g at th

e veg

etated tran

sition fro

m

un

veg

etated b

ay/riv

er. How

ever, if it b

ecom

es evid

ent th

at less than

20

% o

f a qu

adrat is v

egetated

, mo

ve to

the left o

r right o

f the tran

sect until a sp

ot is fo

und w

here th

is criterion is m

et. (The b

otan

ical pro

toco

l in th

is gu

ideb

ook is n

ot in

tend

ed to

assess exten

t of u

nv

egetated

area in

a wetlan

d. T

his is ad

dressed

only

by in

dicato

r #28).

4. In

narro

w m

arshes, th

e use o

f on

ly tw

o sh

ort tran

sects cou

ld resu

lt in q

uad

rats alon

g each

transect b

eing

closer th

an 2

m to

each o

ther. T

o

avo

id th

is, dep

loy

add

ition

al transects p

erpen

dicu

lar to th

e bay

or riv

er until at least th

e 2m

spacin

g is estab

lished

betw

een q

uad

rats as well

as betw

een tran

sects. In rare in

stances, it m

ay also

be n

ecessary to

chan

ge tran

sect orien

tation

from

perp

end

icular to

ob

liqu

e.


Dat

a F

orm

B1.

R

apid

Ind

icat

ors

of

Fu

nct

ion

Th

at M

ay b

e E

stim

ated

Thi

s fo

rm a

nd th

e su

cces

sive

one

(Fo

rm B

2) in

clud

e in

dica

tors

kno

wn

from

tech

nica

l lite

ratu

re o

r re

ason

ed e

colo

gica

l pri

ncip

les

to b

e as

soci

-at

ed w

ith o

ne o

r m

ore

of th

e 12

key

fun

ctio

ns o

f tid

al w

etla

nds.

Som

e of

the

indi

cato

rs w

ere

corr

elat

ed s

tatis

tical

ly w

ith o

ne o

r m

ore

indi

ca-

tors

of

Ris

k fr

om F

orm

A1.

Oth

ers

wer

e un

corr

elat

ed, e

ither

due

to th

e im

prec

isio

n w

ith w

hich

they

and

/or

the

Ris

k in

dica

tors

wer

e es

ti-m

ated

, or

to th

eir

bein

g in

trin

sica

lly u

naff

ecte

d by

hum

an a

ctiv

ities

. T

he u

ncor

rela

ted

func

tions

wer

e in

clud

ed b

ecau

se o

f th

eir

impo

rtan

ce to

asse

ssin

g th

e fu

nctio

ns, a

s do

cum

ente

d in

Par

t 2 o

f th

is g

uide

book

. N

ote:

A h

ighe

r nu

mbe

r fo

r a

part

icul

ar in

dica

tor

belo

w d

oes

not a

lway

sm

ean

grea

ter

func

tion–

the

num

ber

depe

nds

on th

e fu

nctio

n an

d th

e in

dica

tor.

Ita

liciz

ed te

rms

are

defi

ned

in th

e la

st c

olum

n. A

bbre

viat

ions

for

func

tions

in th

e la

st c

olum

n ar

e sh

own

in A

ppen

dix

B.

©20

06 H

GM

Gui

debo

okH

ydro

geom

orph

ic A

sses

smen

t Gui

debo

ok fo

r Tid

al W

etla

nds

of th

e O

rego

n C

oast

, Par

t 1 –

Aug

ust 2

006

App

endi

x A

. Dat

a F

orm

B1,

Intr

o.


©2006 H

GM

Guidebook

Page 1/12

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

1

cod

e in

dicato

r scale/sco

re g

uid

ance

0

1

2

3

-4

5-6

7

-8

9-1

0

11-1

2

13-1

4

15-1

6

>1

5

= 0

.01

= 0

.1

= 0

.2

= 0

.3

= 0

.4

= 0

.5

= 0

.6

= 0

.7

= 0

.8

= 0

.9

= 1

.0

25. F

loo

d

Imag

ine th

e wetlan

d u

nder each

tidal co

nditio

n listed

belo

w.

What %

of th

e wetlan

d’s area (in

cludin

g its in

ternal tid

al chan

nels)

is likely

to b

e accessible to young anadromous fish

? A

s your an

swer, select o

ne n

um

ber fro

m each

row

, then

sum

the

fou

r nu

mb

ers and

use th

eir sum

with

the scale o

n th

e righ

t to

gen

erate a score fo

r the b

ox

.

du

ring

: 0%

(n

on

e)

1-10%

10-50%

50-90%

>90%

Mo

nth

ly low

tide

0

4

5

6

7

Daily lo

w tid

e 0

3

4

5

6

D

aily hig

h tid

e 0

2

3

4

5

M

on

thly h

igh

tide

0

1

2

3

4

sco

re #25:

certain

ty #25:

Assu

me co

nd

ition

s are averag

ed o

ver F

ebru

ary—

Jun

e. If th

e site cann

ot b

e visited

repeated

ly, an

swer th

is based

o

n v

isual estim

ation

of th

e top

og

raph

y o

f the w

etland

relativ

e to th

e tidal am

plitu

de rep

orted

from

the clo

sest m

onito

ring statio

n in

the estu

ary (see T

idal range in O

regon estuaries, belo

w) o

r imp

rov

ed lo

cal data (w

here

availab

le). S

almo

nid

distrib

utio

n m

aps are av

ailable o

n th

e intern

et at: rain

bo

w.d

fw.state.o

r.us/n

rimp/in

form

ation

/fishd

istmap

s.h

tm

Used

for: X

pt, A

fish, M

fish, R

fish, D

ux, L

bird

M,

[NF

W].

score #25:

certainty #25:


estu

ary

loca

tion

da

ily

rang

e

(ft.

)

mon

thly

ra

nge

(f

t.)

es

tuar

y lo

cati

on

daily

ra

nge

(f

t.)

mon

thly

ra

nge

(f

t.)

es

tuar

y lo

cati

on

daily

ra

nge

(f

t.)

mon

thly

ra

nge

(f

t.)

Nec

anic

um

Sea

sid

e 4

.7

5.8

T

aft

5.0

6

.1

Win

ches

ter

5.1

6

.9

Bri

gh

ton

5

.9

7.8

Sile

tz

Ker

nv

ille

4

.6

6.6

Um

pqua

Ree

dsp

ort

5

.1

6.7

Wh

eele

r 5

.9

7.6

S

o.

Bea

ch

6.3

8

.3

mo

uth

5

.2

7.0

Neh

alem

Neh

alem

5

.6

7.2

Yaq

uina

Yaq

uin

a 6

.2

8.2

C

har

lest

on

5

.7

7.5

Bar

vie

w

6.2

8

.2

Wal

dp

ort

5

.8

7.7

E

mp

ire

4.9

6

.7

Gar

ibal

di

5.9

7

.8

Als

ea

Dri

ft C

r.

5.0

6

.2

Coo

s

Co

os

Bay

5

.6

7.3

Bay

Cit

y

5.4

7.1

m

ou

th

5.5

7

.3

Coq

uille

B

andon

5

.2

7.0

Till

amoo

k

Til

lam

oo

k

5.2

6

.6

Flo

ren

ce

5.4

7

.3

Rog

ue

Wed

der

bu

rn

4.9

6

.7

Net

arts

W

his

key

Cr.

4

.8

7.8

C

ush

man

5

.5

7.3

C

hetc

o B

roo

kin

gs

5.1

7

.0

Sand

Lak

e --

- 5

.7

---

Tie

rnan

5

.9

7.7

Nes

tucc

a m

ou

th

5.8

7

.6

Sius

law

Map

leto

n

6.2

8

.0

Tid

al r

ang

e in

Ore

go

n e

stu

arie

s (m

ost

ly f

rom

Ham

ilto

n 1

984)

. U

se b

ette

r lo

cal d

ata

wh

en a

vaila

ble

.

©20

06 H

GM

Gui

debo

okP

age

2/12

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m B

1


©2006 H

GM

Guidebook

Page 3/12

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

1

cod

e in

dicato

r sco

re g

uid

ance

26. S

had

e P

ercent o

f the en

tire wetlan

d’s v

egetated

area that is shaded

by

trees or to

pograp

hy:

%

sco

re <

1%

0.01

1-1

0%

0.50

>10%

1.00

sco

re #26:

certain

ty #26:

To

cou

nt, it m

ust b

e shad

ed fo

r 4+

ho

urs d

urin

g an

av

erage clo

ud

less day

. In

clud

e parts o

f the internal channel n

etwo

rk th

at are in

un

dated

mo

st day

s and

are shad

ed b

y d

eep in

cision

, lo

gs, o

r un

dercu

t ban

ks. Internal channels in

clud

e bo

th

tribu

tary ch

annels (flo

win

g fro

m u

plan

ds) an

d b

lind

ch

annels (flo

odin

g w

ith th

e inco

min

g tid

e). U

sed fo

r: AP

rod, [W

Q, X

pt, In

v, A

fish, M

fish, R

fish,

NF

W, S

bird

, Lb

irdM

].

27. S

had

eLM

[S

kip

if no

low

marsh

is presen

t.] P

ercent o

f only the lo

w m

arsh th

at is shaded b

y trees o

r to

po

grap

hy:

%

sco

re <

1%

0.01

1-1

0%

0.50

>10%

1.00

sco

re #27:

certain

ty #27:

See ab

ove.

As a rem

ind

er, “low

marsh

” is defin

ed as areas flo

od

ed

by th

e tide d

urin

g th

e majo

rity o

f day

s durin

g m

ost

month

s of th

e year. L

ow

marsh

is not lim

ited ju

st to

areas that flo

od ev

ery d

ay.

Used

for: A

fish.

28. B

are A

rea of bare substrate, in

clud

ing

pannes, shallo

w p

oo

ls, and

tideflats w

ider th

an 2

m an

d lo

cated w

ithin th

e wetlan

d:

area

score

0-4

sq. m

0.01

4-1

00 sq

.m

0.25 1

00-2

,500

sq.m

0.50

2,5

00-1

0,0

00 sq

.m

0.75 >

10,0

00 sq

.m

1.00

sco

re #28:

certain

ty #28:

Pannes =

shallo

w m

ostly

-bare d

epressio

ns in

the m

arsh

surface an

d aren

’t curren

tly a p

art of tid

al chan

nels.

Assess co

nditio

n as at lo

w tid

e. U

sed fo

r: AP

rod

, NF

W, D

ux

, Sb

ird, [W

Q, X

pt, In

v,

Afish

, Mfish

, Rfish

, NF

W, S

bird

, Lbird

M].

score #26:

certainty #26:

score #27:

certainty #27:

score #28:

certainty #28:


©20

06 H

GM

Gui

debo

okP

age

4/12

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m B

1

cod

e in

dic

ato

r sc

ore

g

uid

ance

29

. P

ann

es

Are

a on

ly o

f pa

nnes

an

d s

hal

low

isol

ated

po

ols

(n

ot

tid

efla

ts):

area

sc

ore

0

-4 s

q. m

0.

01

4-1

00 s

q.m

0.

25

100-2

,500

sq

.m

0.50

2

,500-1

0,0

00 s

q.m

0.

75

>10,0

00 s

q.m

1.

00

sc

ore

#29

:

ce

rtai

nty

#29

:

Isol

ated

= l

ackin

g a

su

rfac

e co

nnec

tion t

o o

ther

wat

ers

duri

ng d

aily

low

tid

e U

sed

fo

r:

Inv

, R

fish

, [A

fish

, M

fish

, S

bir

d, L

bir

dM

].

30.

Tra

nA

ng

T

rans

itio

n an

gle

along m

ost

of

the

wet

land e

xter

nal e

dge:

tran

siti

on

an

gle

sc

ore

g

rad

ual

, o

r st

eep

bu

t st

able

0.

01

stee

p, w

ith

ex

ten

siv

e er

osi

on

an

d u

nd

ercu

ttin

g

1.00

sc

ore

#30

:

ce

rtai

nty

#30

:

Ext

erna

l edg

e =

the

edge

bet

wee

n t

he

mar

sh a

nd

adjo

inin

g b

ay o

r ti

dal

riv

er.

Use

d f

or:

W

Q.

31.

Up

Ed

ge

Per

cent

of

the

wet

land’s

enti

re p

erim

eter

that

is

upla

nd,

i.e.

,

neith

er w

ater

, non-t

idal

wet

land, nor

tidef

lat:

%

sco

re

<1

0.

01

1-2

5

0.25

2

5-5

0

0.50

5

0-7

5

0.75

>

75

1.

00

sc

ore

#31

:

ce

rtai

nty

#31

:

Per

imet

er =

the

wet

lan

d’s

ed

ge

wit

h u

pla

nd

plu

s w

ith

unveg

etat

ed w

ater

or

tidef

lat.

D

o n

ot

incl

ude

inte

rnal

ch

annel

s in

the

calc

ula

tion o

f th

e m

arsh

per

imet

er.

If

po

ssib

le, u

se c

om

pu

ter

GIS

so

ftw

are

to m

easu

re t

he

per

imet

er a

nd

ed

ges

. U

sed

fo

r: W

Q,

Lb

ird

M.

sco

re #

29:

cert

ain

ty #

29:

sco

re #

30:

cert

ain

ty #

30:

sco

re #

31:

cert

ain

ty #

31:


©2006 H

GM

Guidebook

Page 5/12

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

1

cod

e in

dicato

r sco

re g

uid

ance

32. L

WD

chan

N

um

ber o

f pieces o

f large woody debris (L

WD

) in w

etland’s tid

al ch

annel n

etwo

rk:

# L

WD

in ch

ann

el sco

re 0

, or n

o ch

ann

els presen

t 0.01

1-1

0

0.50 >

10

1.00

sco

re #32:

certain

ty #32:

To

cou

nt, th

e LW

D m

ust h

ave

a diam

eter >1

5 cm

and

a leng

th >

2m

. U

sed fo

r: Inv

, Afish

, [Rfish

, Mfish

, Sb

ird,

Lbird

M].

33. L

WD

marsh

N

um

ber o

f LW

D projecting

at least 1m

above th

e wetlan

d su

rface:

# LW

D

abo

ve surface

sco

re 0

0.01

1-4

0.25

5-9

0.50

10-3

0

0.75 >

30

1.00

sco

re #33:

certain

ty #33:

Used

for: L

bird

M.

34. L

WD

line

Driftw

ood line as % o

f wetlan

d’s u

plan

d ed

ge len

gth

:

%

score

0

0.01 1

-9

0.25 1

0-2

9

0.50 3

0-5

9

0.75 >

59

1.00

sco

re #34:

certain

ty #34:

Driftw

ood lin

e = L

WD

arranged

natu

rally in

a lin

ear pattern

, usu

ally p

arallel to u

plan

d, as a

result o

f tides. (D

riftwood lin

es are often

close to

th

e elevatio

n o

f annual h

igh tid

e) U

sed fo

r: Inv

, Lb

irdM

, [Afish

, Mfish

, Rfish

, N

FW

, Sb

ird.]

score #32:

certainty #32:

score #33:

certainty #33:

score #34:

certainty #34:


©20

06 H

GM

Gui

debo

okP

age

6/12

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m B

1

cod

e in

dic

ato

r sc

ale/

sco

re

gu

idan

ce

35.

Tri

bL

C

um

ula

tiv

e le

ng

th (

in m

iles

) o

f fi

sh-a

cces

sib

le n

on

-tid

al t

ribu

tary

ch

anne

ls t

hat

fee

d i

nto

the

wet

land:

le

ng

th

sco

re

<3

mi.

0.

01

3-1

0m

i.

0.05

>

10

mi.

1.

00

sco

re #

35:

ce

rtai

nty

#35

:

Mea

sure

on

ly t

he

trib

uta

ry c

han

nel

s th

at p

ass

thro

ug

h t

he

wet

lan

d. D

on’t

co

un

t th

e ad

join

ing

mai

n r

iver

ch

ann

el.

Est

imat

e le

ng

th b

egin

nin

g a

t th

e w

etla

nd

’s u

pla

nd

mar

gin

an

d e

xte

ndin

g t

o t

he

upst

ream

lim

it o

f fi

sh-a

cces

sible

wat

ers.

O

DF

W h

as i

nfo

rmat

ion

on

sal

mo

nid

use

are

as:

rain

bo

w.d

fw.s

tate

.or.

us/

nri

mp

/in

form

atio

n/f

ish

dis

tmap

s.h

tm

Use

d f

or:

X

pt,

Inv,

Afi

sh, N

FW

, D

ux,

Lb

irdM

, [M

fish

, R

fish

, S

bir

d].

36.

Fre

sh

Types

of

fres

hwat

er s

ourc

es t

hat

fee

d t

he

wet

land i

nte

rnal

ly.

Sel

ect

the

max

imu

m s

core

in

eac

h gro

up

and

th

en s

um

th

e tw

o

max

ima:

Gro

up

A:

Flo

win

g in

to t

he

wet

lan

dsc

ore

pere

nnia

l fre

sh t

ributa

ry

4 in

term

itten

t fre

sh t

rib

uta

ry o

r st

orm

wat

er p

ipe

2 n

eith

er

0

Gro

up

B:

Ad

join

ing

on

th

e u

ph

ill s

ide

sco

re

larg

e* n

on

-tid

al f

resh

wat

er w

etla

nd

, po

nd

, or

spri

ng

4

smal

l non-t

idal

wet

land, se

ep,

or

hydr

ic s

oil

pat

ch

3 oth

er l

and c

over

, an

d t

idal

wet

land i

s not

an i

slan

d

1 ti

dal

wet

land

occ

up

ies

nea

rly a

ll o

f an

isl

and

0 *

wid

er t

han

th

e ti

dal

wet

lan

d (

wid

th m

easu

red

per

pen

dic

ula

r to

slo

pe)

sum

= s

core

0

= 0

.01

1

= 0

.1

2

= 0

.2

3

= 0

.3

4

= 0

.5

5

= 0

.7

6

= 0

.8

7

= 0

.9

8

= 1

.00

sco

re #

36:

ce

rtai

nty

#36

:

Do n

ot

count

maj

or

river

s ad

join

ed b

y t

he

wet

land a

s fr

esh

wat

er s

ou

rces

. P

eren

nial

tri

bu

tari

es f

low

yea

r-ro

und

m

ost

yea

rs.

Int

erm

itten

t tri

buta

ries

flo

w s

easo

nal

ly a

nd h

ave

reco

gniz

able

chan

nel

s ex

tendin

g u

phil

l at

lea

st t

wic

e th

e w

idth

of

the

tidal

mar

sh. N

on-t

idal

wet

land

s on

th

e O

reg

on

Coas

t ar

e ty

pic

ally

dom

inat

ed b

y a

lder

, w

illo

w,

catt

ail,

skunk

cabbag

e, s

lough s

edge,

sm

all-

fruit

ed b

ulr

ush

, an

d w

ater

par

sley

(so

me

of

thes

e occ

ur

to a

les

ser

deg

ree

in t

idal

w

etla

nds)

. A

djoi

ning

mea

ns

pre

sen

t w

ith

in 1

0m

.

Ore

gon c

oas

tal

soil

s co

nsi

der

ed t

o b

e hy

dric

are

Bla

cklo

ck,

Bra

gto

n,

Bra

llie

r, B

renner

, C

het

co,

Cla

tsop,

Coquil

le,

Dep

oe,

Flu

vaq

uen

ts, H

ebo,

Hec

eta,

Lan

glo

is,

Riv

erw

ash,

Wil

lanch

, an

d Y

aquin

a.

Man

y o

ther

s co

nta

in h

ydri

c in

clu

sio

ns.

U

sed

fo

r: A

Pro

d, A

fish

, N

FW

, D

ux

, L

bir

dM

, [W

Q, X

pt,

In

v, M

fish

, R

fish

, S

bir

d].

sco

re #

35:

cert

ain

ty #

35:

sco

re #

36:

cert

ain

ty #

36:


©2006 H

GM

Guidebook

Page 7/12

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

1

cod

e in

dicato

r scale/sco

re g

uid

ance

37. W

idth

W

etland’s wid

th at its w

idest p

art:

wid

th ft.

score

wid

th ft.

score

<1

00

0.01

600–

700

0.6

100–

200

0.1

700–

800

0.7

200–

300

0.2

800–

900

0.8

300–

400

0.3

900–

1,0

00

0.9

400–

500

0.4

>1

,00

0

1.0 5

00–

600

0.5

sco

re #37:

certain

ty #37:

Measu

re this as a p

erpen

dicu

lar line fro

m aq

uatic

(unveg

etated riv

er or b

ay ed

ge o

r tideflat) to

uplan

d

edge. If site is an

island w

ith n

o u

plan

d, m

easure to

the

water ed

ge o

n o

pposite sid

e of th

e island.

Used

for: W

Q, X

pt, D

ux

, Sb

ird.

38. M

ud

W

Max

imu

m w

idth

of larg

est tideflat that ad

join

s the w

etland

:

wid

th ft.

score

wid

th ft.

score

<1

00

0.01

600–

700

0.6

100–

200

0.1

700–

800

0.7

200–

300

0.2

800–

900

0.8

300–

400

0.3

900–

1,0

00

0.9

400–

500

0.4

>1

,00

0

1.0 5

00–

600

0.5

sco

re #38:

certain

ty #38:

Measu

re this u

sing a U

SG

S to

pog

raph

ic map

or

(preferab

ly) field

ob

servatio

n at lo

w tid

e, as a perp

endicu

lar to th

e extern

al edge o

f wetlan

d, o

r m

easure it to

the ex

ternal ed

ge o

f oth

er wetlan

ds o

r flats on eith

er side (co

ntig

uo

us to

the w

etland b

eing

measu

red).

Used

for: N

FW

, Sb

ird.

39. R

oo

st

[Sk

ip if th

e wetlan

d co

ntain

s no

low

marsh

.] N

um

ber o

f types o

f poten

tial shorebird roosts with

in 1

.5 m

i. of th

e cen

ter of th

e wetlan

d (ch

eck all th

at are presen

t): _

_ treeless h

igh

marsh

, mo

stly w

ider th

an 3

00

ft _

_ treeless u

nin

hab

ited islan

ds (d

ry at h

igh

tide)

__ b

eaches o

r bars, m

ostly

wid

er than

100 ft at h

igh tid

e _

_ n

on

tidal m

arsh/p

on

d, m

ostly

wid

er than

30

0 ft

__ u

nv

egetated

dik

e or jetty

__ seaso

nally

floo

ded

pastu

re >4

0 acres

__ sew

age treatm

ent lag

oo

n

Ad

d th

e nu

mb

er of ch

eckm

arks an

d u

se scale at righ

t to d

erive sco

re.

0 =

0.0

1

1 =

0.2

5

2-3

= 0

.50

4

-5 =

0.7

5

6-7

= 1

.00

score #39:

certain

ty #39:

Inclu

de th

ese if they

occu

r with

in th

e wetlan

d as w

ell. U

sed fo

r: Sb

ird.

score #37:

certainty #37:

score #38:

certainty #38:

score #39:

certainty #39:


©20

06 H

GM

Gui

debo

okP

age

8/12

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m B

1

cod

e in

dic

ato

r sc

ore

g

uid

ance

40

. Is

lan

d

Wet

lan

d c

om

pri

ses

all

or

par

t o

f an

un

inh

abit

ed is

land

:

d

escr

ipti

on

sc

ore

w

etla

nd

co

mp

rise

s al

l o

r p

art

of

isla

nd

; an

d th

e is

land

con

tain

s es

sen

tial

ly n

o h

igh

mar

sh o

r u

nd

evel

op

ed u

pla

nd

, i.

e.,

is c

om

ple

tely

under

wat

er d

uri

ng

dai

ly h

igh

tid

e

0.01

wet

lan

d c

om

pri

ses

all

or

par

t o

f is

lan

d;

and

the

isla

nd

con

tain

s so

me

hig

h m

arsh

and

/or

un

dev

elo

ped

up

lan

d,

this

b

ein

g le

ss t

han

th

e ar

ea o

f lo

w m

arsh

0.33

wet

lan

d c

om

pri

ses

all

or

par

t o

f is

lan

d;

and

the

isla

nd

con

tain

s so

me

hig

h m

arsh

and

/or

un

dev

elo

ped

up

lan

d,

this

b

ein

g g

reat

er t

han

the

area

of

low

mar

sh

0.66

wet

land d

oes

not

com

pri

se a

ll o

r par

t of

isla

nd

1.00

sco

re #

40:

ce

rtai

nty

#40

:

Isla

nd =

lan

d n

ot

per

man

entl

y f

looded

and

com

ple

tely

sep

arat

ed f

rom

upla

nd a

t lo

w t

ide

by

wat

er a

t le

ast

3 f

t dee

p a

nd 2

0 f

t w

ide.

U

sed

fo

r:

Inv

, D

ux

, L

bir

dM

, [A

fish

, M

fish

, R

fish

, S

bir

d, N

FW

].

sco

re #

40:

cert

ain

ty #

40:

cod

e in

dic

ato

r sc

ore

g

uid

ance

41

. F

etch

D

irec

tion a

nd d

ista

nce

of

exte

rnal

edg

e’s

exp

osu

re t

o i

nte

nse

wav

e an

d/or

riv

er c

urre

nt a

ctio

n.

En

ter

the

max

imu

m a

pp

rop

riat

e n

um

ber

in

th

e b

ox

to

th

e ri

gh

t.

S

E, S

, or

SW

exp

osu

re, a

nd

dis

tan

ce is

:

<100

’ 10

0 –

1,00

0’

>1,0

00’

Ext

ern

al e

dg

e m

ost

ly

pro

tect

ed b

y d

ikes

, le

vees

, up

lan

d

top

og

rap

hy.

0.01

(o

r m

arsh

’s

exte

rnal

ed

ge

face

s a

dir

ecti

on

oth

er t

han

SE

, S

. or

SW

)

0.01

0.

01

Gra

du

al d

rop

-off

to

d

eep

er w

ater

; an

d

larg

e-b

oat

tra

ffic

an

d

seve

re r

iver

flo

od

s ar

e b

oth

infr

equ

ent.

0.3

0.6

0.8

Sh

arp

dro

p-o

ff t

o

dee

per

wat

er;

and

/or

larg

e-b

oat

tra

ffic

n

earb

y; a

nd

/or

larg

e ri

ver

flo

od

s ar

e fr

equ

ent.

No

p

rote

ctio

n.

Dri

ftw

oo

d

oft

en a

bu

nd

ant.

0.5

0.8

1.00

sc

ore

#41

:

ce

rtai

nty

#41

:

Dro

poff

= t

he

slo

pe

and

bat

hym

etry

of

dee

per

-wat

er

area

s w

ith

in a

bo

ut

30

ft

of

the

mar

sh e

dg

e, n

ot

just

to

th

e m

arsh

ed

ge

itse

lf.

If l

oca

l w

ind d

ata

show

str

onges

t w

aves

consi

sten

tly

com

ing

fro

m a

dir

ecti

on

oth

er t

han

SE

, S

, o

r S

W, y

ou

m

ay m

odif

y t

he

hea

der

s on t

his

tab

le t

o t

hat

dir

ecti

on.

Use

d f

or:

W

Q, In

v, D

ux

, [A

fish

, M

fish

, R

fish

, N

FW

, S

bir

d, L

bir

dM

].

sco

re #

41:

cert

ain

ty #

41:


©2006 H

GM

Guidebook

Page 9/12

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

1

cod

e in

dicato

r scale/sco

re g

uid

ance

42. P

form

N

um

ber o

f easily-reco

gnizab

le vegetation structures presen

t with

in

the w

etland. C

heck

all that p

redom

inate o

ver at least 1

00 sq

.ft: __ larg

e robust g

rass-like p

lants (e.g

., bulru

sh, cattail)

__

oth

er large n

ative g

rass-like p

l ants (m

ostly

>8 in

ches lo

ng, e.g

., D

eschampsia, H

ordeum, Juncus )

__

fleshy

, succu

lent p

l ants (e.g

., pick

leweed

) _

_ o

ther n

on

-wo

od

y p

lants (e.g

., saltmarsh

aster, oth

er forb

s) _

_ nurse logs su

pportin

g p

lants taller th

an 1

ft. _

_ su

bm

ersed aq

uatics (e.g

., wig

e on

grass o

r eelgrass) in

intern

al ch

annels o

r pools o

r extern

ally w

ithin

50 ft.

Deriv

e score b

y co

mp

aring th

e num

ber o

f items ch

ecked

abo

ve w

ith

the scale in

the n

ext co

lum

n.

0-2

= 0

.01

3

= 0

.25

4

= 0

.50

5

= 0

.75

6

= 1

.00

score #42:

certain

ty #42:

Nurse logs =

large lo

gs o

r stum

ps p

resent o

n th

e marsh

su

rface which

, becau

se of th

e elevated

substrate th

ey

pro

vid

e, pro

tect germ

inatin

g p

lants o

n to

p o

f the lo

g

from

poten

tially leth

al long-d

uratio

n flo

odin

g an

d h

igh

salinity

. U

sed fo

r: AP

rod, X

pt, In

v, D

ux, L

bird

M, [W

Q, A

fish,

Mfish

, Rfish

, NF

W, S

bird

].

43. F

orm

Div

Num

ber o

f easily-reco

gnizab

le vegetation forms w

ithin

the w

etland

or directly adjoining

its uplan

d ed

ge, fro

m th

is list. For liv

e veg

etation, th

ese must b

e presen

t along >

5%

of u

plan

d ed

ge o

r that

com

prise >

5%

of th

e wetlan

d area:

_

_ g

razed o

r mo

wed

grass an

d/o

r forb

s __ u

ngrazed

& u

nm

ow

ed g

rass and/o

r forb

s _

_ sh

rub

s 2-6

ft tall, con

ifer __ sh

rubs 2

-6 ft tall, d

eciduous

__

shru

bs 6

-20

ft tall, con

ifer __ sh

rubs 6

-20 ft tall, d

eciduous

__ liv

e trees 20-6

0 ft tall, co

nifer

__ liv

e trees 20-6

0 ft tall, d

eciduous

__ liv

e trees >60 ft tall, co

nifer

__ liv

e trees >60 ft tall, d

eciduous

__

stand

ing

snag

s, <6

” diam

eter _

_ stan

din

g sn

ags, >

6” d

iameter

Deriv

e score b

y co

mp

aring th

e num

ber o

f items ch

ecked

abo

ve w

ith

the scale in

the n

ext co

lum

n.

1 =

0.0

1

2 =

0.2

3

= 0

.3

4 =

0.4

5

= 0

.5

6 =

0.6

7

= 0

.7

8 =

0.8

9

= 0

.9

>9

= 1

.0

sco

re #43:

certain

ty #43:

Directly adjoining

= u

nobscu

red b

y a tree can

opy.

Used

for: In

v, L

bird

M, [A

fish, M

fish, R

fish, N

FW

, S

bird

].

score #42:

certainty #42:

score #43:

certainty #43:


©20

06 H

GM

Gui

debo

okP

age

10/1

2H

ydro

geom

orph

ic A

sses

smen

t Gui

debo

ok fo

r Tid

al W

etla

nds

of th

e O

rego

n C

oast

, Par

t 1 –

Aug

ust 2

006

App

endi

x A

. Dat

a F

orm

B1

cod

e in

dic

ato

r sc

ore

g

uid

ance

44

. A

lder

P

erce

nt

of

up

lan

d e

dg

e bo

unded

(w

ith

in 5

0 f

t.)

by a

lder

:

%

sco

re

<1

(o

r n

o u

pla

nd

) 0.

01

1-1

0

0.33

1

0-5

0

0.66

>

50

1.

00

sc

ore

#44

:

ce

rtai

nty

#44

:

Oth

er d

ecid

uo

us

pla

nt

spec

ies

kn

ow

n t

o f

ix n

itro

gen

(n

ot

sim

ply

tak

e it

up f

rom

th

e so

il)

may

be

incl

ud

ed a

s w

ell.

U

sed

fo

r:

Inv

, [A

fish

, M

fish

, R

fish

, N

FW

, S

bir

d,

Lbir

dM

].

45.

Eel

g

Pre

sen

ce o

f ee

lgra

ss (

eith

er s

pec

ies)

:

pre

sen

ce

sco

re

not

0d

etec

ted

0.

1 o

bs

50er

ved

only

in a

djo

inin

g w

ater

s or

flat

s 0.

o

bs

00er

ved

wit

hin

the

wet

land’s

inte

rnal

chan

nel

s 1.

sc

ore

#45

:

ce

rtai

nty

#45

:

Bas

ed e

ith

er o

n o

bse

rvat

ion

s fr

om

sh

ore

(u

p t

o 5

0 f

t.

away

), b

oat

, or

publi

shed

rep

ort

s or

map

s.

“Cer

tain

ty”

should

be

score

d l

ow

if

no e

elgra

ss i

s det

ecte

d b

ecau

se

det

ecti

on a

t a

dis

tance

can

be

dif

ficu

lt o

r im

poss

ible

. U

sed

fo

r:

Inv

, D

ux

, [A

fish

, M

fish

, R

fish

, N

FW

, S

bir

d,

Lbir

dM

].

46.

So

ilFin

e P

redo

min

ant s

oil t

extu

re i

n m

ost

of

the

wet

land:

so

il te

xtu

re

sco

re

coar

se s

and

, g

rav

el

0.01

fi

ne

san

d

0.40

si

lt,

loam

, m

uck

, pea

t 1.

00

sc

ore

#46

:

ce

rtai

nty

#46

:

Ass

ess

this

fro

m c

ounty

soil

surv

ey m

aps,

unle

ss b

ette

r dat

a ar

e av

aila

ble

fro

m o

nsi

te e

xam

inat

ion o

f th

e upper

12 i

nch

es o

f th

e so

il a

t se

ver

al l

oca

tions

in t

he

wet

land.

P

redo

min

ant =

occ

up

yin

g t

he

gre

ates

t pro

port

ion o

f th

e su

rfac

e ar

ea o

f a

site

. U

sed

fo

r: W

Q.

sco

re #

44:

cert

ain

ty #

44:

sco

re #

45:

cert

ain

ty #

45:

sco

re #

46:

cert

ain

ty #

46:


©2006 H

GM

Guidebook

Page 11/12

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

1

cod

e in

dicato

r sco

re g

uid

ance

47. E

stuS

al T

idal marsh acreage in

this w

etland’s m

ajor estu

ary:

d

escriptio

n

score

Tid

al marsh

es are absen

t (or n

early ab

sent) fro

m tw

o o

f the

three salin

ity zo

nes (fresh

, brack

ish, salin

e): N

etarts, Siltco

os, T

enm

ile, Elk

Riv

er, Ch

etco.

0.01

Tid

al marsh

es are absen

t (or n

early so

) from

one o

f the

three salin

ity zo

nes, w

ith o

ne o

f the tw

o rem

ainin

g zo

nes

hav

ing

mu

ch m

ore m

arsh acreag

e than

the o

ther:

San

d L

ake, S

almon, B

eaver C

r., Coquille,

New

Riv

er, Ro

gu

e, Win

chu

ck.

0.33

Tid

al marsh

es are presen

t in all th

ree zones, w

ith o

ne zo

ne

contain

ing m

ore th

an 5

0%

of th

e estuary

’s marsh

acreage:

Neh

alem, T

illamo

ok

, Nestu

cca, Yaq

uin

a, Alsea, C

oo

s.

0.66

Tid

al marsh

es are presen

t in all th

ree zones, w

ith n

o zo

ne

contain

ing m

ore th

an 5

0%

of th

e estuary

’s marsh

acreage:

Necan

icum

, Siletz, S

iuslaw

, Um

pq

ua.

1.00

sco

re #47:

certain

ty #47:

The salin

ity zo

nes are n

ot b

a sed o

n salin

ity w

ithin

the

wetlan

d, b

ut rath

er in th

e adjo

inin

g b

ay o

r river.

These categ

orizatio

ns o

f estuaries are b

ased o

n v

ery

limited

salinity

data an

d m

ay b

e revised

. U

sed fo

r: Afish

, Mfish

, Rfish

, [WQ

, Inv

, NF

W, S

bird

, L

bird

M].

score #47:

certainty #47:


©20

06 H

GM

Gui

debo

okP

age

12/1

2H

ydro

geom

orph

ic A

sses

smen

t Gui

debo

ok fo

r Tid

al W

etla

nds

of th

e O

rego

n C

oast

, Par

t 1 –

Aug

ust 2

006

App

endi

x A

. Dat

a F

orm

B1

cod

e in

dic

ato

r sc

ore

g

uid

ance

48

. S

eaJo

in

Est

uar

y c

onne

ctio

n w

ith

oce

an.

d

escr

ipti

on

sc

ore

E

stuar

ine

connec

tion t

o o

cean

is

lost

reg

ula

rly,

at l

east

once

ev

ery 1

-10 y

rs (

som

e “b

lind”

estu

arie

s an

d c

oas

tal

lagoons)

. 0.

01

Usu

ally

connec

ted t

o o

cean

, an

d a

lmost

the

enti

re e

stuar

y i

s sa

line

due

to m

inim

al f

resh

wat

er i

nput

(as

in s

om

e “b

ar b

uil

t” e

stuar

ies)

.

0.50

Alw

ays

connec

ted t

o o

cean

, w

ith

mu

ch f

resh

wat

er i

nput

from

fe

eder

str

eam

s an

d/o

r ri

ver

. 1.

00

sc

ore

#48

:

ce

rtai

nty

#48

:

Use

d f

or:

A

fish

, M

fish

, [N

FW

].

49.

Est

u%

WL

R

elat

ive

dom

inan

ce o

f un

dike

d ti

dal w

etla

nds

in t

his

est

uar

y.

U

se t

he

score

fro

m t

he

appro

pri

ate

estu

ary i

n t

his

lis

t:

Als

ea =

0.8

; B

eav

er C

r .=

0.9

; C

het

co =

0.1

; C

oos

Bay

= 0

.7;

C

oquil

le =

0.5

; E

cola

= 0

.5;

Elk

R. =

0.3

; E

uch

re-G

reggs

Cr.

= 0

.3;

N

ecan

icum

= 0

.7;

Neh

alem

= 0

.9;

Nes

tucc

a =

0.4

; N

etar

ts =

1.0

;

New

Riv

er =

0.8

; P

isto

l =

0.2

; R

og

ue

= 0

.2;

Sal

mo

n =

1.0

;

San

d L

ake

= 0

.3;

Sil

etz

= 0

.9;

Sil

tcoos

= 0

.5;

Siu

slaw

= 1

.0;

S

ixes

= 0

.2;

Ten

Mil

e =

0.8

; T

illa

mook =

0.6

; T

wo M

ile

= 0

.4;

U

mp

qu

a =

0.7

; W

inch

uck

= 0

.1;

Yaq

uin

a =

0.8

sc

ore

#49

:

ce

rtai

nty

#49

:

Nu

mb

ers

wer

e b

ased

on

rat

io o

f ti

dal

mar

sh t

o

subti

dal

wat

er, as

wel

l as

on t

ota

l ac

res

of

tidal

m

arsh

. T

hey

do

no

t ac

cou

nt

for

pre

vio

us

exte

nt

or

his

tori

cal

loss

es o

f ti

dal

wet

lan

ds.

U

sed

fo

r: A

fish

, [N

FW

].

sco

re #

48:

cert

ain

ty #

48:

sco

re #

49:

cert

ain

ty #

49:


This form

includes indicators known from

technical literature or reasoned ecological principles to be associated with one or m

ore of the 12key functions of tidal w

etlands. Some of the indicators w

ere correlated statistically with one or m

ore indicators of risk from Form

A1. O

th-ers w

ere uncorrelated, either due to the imprecision w

ith which they and/or the R

isk indicators were estim

ated, or to their bei ng intrinsicallyunaffected by hum

an activities. The uncorrelated functions w

ere included because of their importance to assessing the functions, as docu-

mented in Part 2 of this guidebook. N

ote: A higher num

ber for a particular indicator below does not alw

ays mean greater function–the

number depends on the function and the indicator. Italicized term

s are defined in the last column. A

bbreviations for functions in the lastcolum

n are shown in A

ppendix B.

Data F

orm

B2. R

apid

Ind

icators o

f Fu

nctio

n R

equ

iring

Aerial

Ph

oto

grap

hs o

r Measu

ring

Eq

uip

men

t

Appendix A

©2006 H

GM

Guidebook

Hydrogeom

orphic Assessm

ent Guidebook for T


regon Coast, P


Appendix A

. Data F

orm B

2, Intro

.


©20

06 H

GM

Gui

debo

okP

age

1/4

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m B

2

cod

e in

dic

ato

r sc

ore

g

uid

ance

50

. W

etF

ield

%

Per

cent

of

land w

ithin

1.5

mi.

th

at a

ppea

rs (

in a

1:2

4,0

00

scal

e ae

rial

photo

gra

ph)

to b

e po

nds,

lak

es, n

on

tid

al m

arsh

, se

wag

e la

goons,

cro

pla

nd

, or

pas

ture

in fl

at te

rrai

n.

%

sc

ore

<

5

0.01

5

-9

0.25

1

0-1

9

0.50

2

0-2

9

0.75

>

29

1.

00

sc

ore

#50

:

ce

rtai

nty

#50

:

Fla

t ter

rain

= s

lop

es l

ess

than

ab

ou

t 1

0%

. A

fter

dra

win

g a

cir

cle

of

1.5

mi.

rad

ius

from

the

wet

land

cen

ter

(4 i

nch

es o

n a

1:2

4,0

00 s

cale

aer

ial

pho

tog

raph

or

map

), m

easu

re t

he

acre

age

of

the

nam

ed c

ov

er t

yp

es a

nd

d

ivid

e b

y 4

5.2

4 t

o g

et t

he

per

cen

t. P

erfo

rmin

g t

his

m

easu

rem

ent

wit

h a

GIS

is

pre

ferr

ed.

If n

o a

cces

s to

aer

ial

ph

oto

gra

ph

s, a

ttem

pt

to e

stim

ate

bu

t sc

ore

cer

tain

ty “

0.0

1”.

U

sed

fo

r: N

FW

, S

bir

d, D

ux

.

51.

Bu

ffC

ov

Per

cent

of

the

area

su

rroundin

g t

his

wet

land t

hat

appea

rs (

in

a 1:2

4,0

00 s

cale

aer

ial

photo

gra

ph)

to b

e de

velo

ped

or

pers

iste

ntly

bar

e.

<5%

6-

14%

15

-24%

>

25%

w

ith

in 1

500

ft:

0.

50

0.25

0.

15

0.10

w

ith

in 3

000

ft:

0.

50

0.20

0.

10

0.01

S

elec

t o

ne

nu

mb

er f

rom

eac

h r

ow

and

su

m t

hem

to

der

ive

the

sco

re.

sc

ore

#51

:

ce

rtai

nty

#51

:

Dev

elop

ed =

law

ns,

lan

dsc

apin

g, p

avem

ent,

bu

ild

ing

s.

Per

sist

ently

bar

e =

bar

e co

mp

acte

d s

oil

or

rock

(not

sand

du

nes

).

Aft

er d

raw

ing a

cir

cle

of

1500 f

t. o

utw

ard f

rom

the

wet

land

cente

r (3

/4 i

nch

on a

1:2

4000 a

eria

l photo

gra

ph o

r m

ap),

su

btr

act

fro

m 1

62

acr

es (

the

area

of

the

circ

le)

the

acre

age

of

any i

ncl

uded

tid

elan

ds.

T

hen

div

ide

the

dev

elo

ped

acr

es y

ou

m

easu

red b

y t

his

num

ber

. D

o l

ikew

ise

for

the

3000’

circ

le,

but

subst

itute

650 f

or

162. M

ult

iply

the

resu

lts

by 1

00 t

o g

et

per

cent.

P

erfo

rmin

g t

his

mea

sure

men

t w

ith a

GIS

is

pre

ferr

ed.

If

no a

cces

s to

aer

ial

photo

gra

phs,

att

emp

t to

es

tim

ate

but

score

cer

tain

ty “

0.0

1”.

U

sed

fo

r: N

FW

, L

bir

dM

.

sco

re #

50:

cert

ain

ty #

50:

sco

re #

51:

cert

ain

ty #

51:


©2006 H

GM

GuidebookP

age 2/4H

ydrogeomorphic A

ssessment G



oast, Part 1 – A

ugust 2006A

ppendix A. D

ata Form

B2

cod

e in

dicato

r sco

re g

uid

ance

52. B

lind

L

Internal channel complexity

. W

hile v

iewin

g a 1

:24

,00

0 scale aerial p

ho

tog

raph

, imag

ine

all the w

etland’s blind channel seg

men

ts strun

g en

d-to

-end

an

d straig

hten

ed o

ut. R

elative to

the w

etland’s w

idth, w

ou

ld

their cu

mu

lative len

gth

be:

len

gth

relative to w

idth

sco

re less th

an h

alf (50%

) 0.01

50

-10

0%

0.20

1-1

.9 tim

es lon

ger

0.40 2

-2.9

times lo

ng

er 0.60

3-3

.9 tim

es lon

ger

0.80 >

3.9

times lo

ng

er 1.00

sco

re #52:

certain

ty #52:

Blind channels =

chan

nels lo

cated en

tirely w

ithin

the w

etland

(do n

ot o

rigin

ate in ad

join

ing u

plan

ds) th

at flood w

ith th

e in

com

ing

tide.

Width

= th

e wetlan

d’s m

axim

um

wid

th m

easured

p

erpen

dicu

lar to ad

join

ing

bay

or riv

er. If n

o access to

aerial ph

oto

grap

hs, attem

pt to

estimate b

ut

score certain

ty “0

.01”.

Used

for: A

Pro

d, W

Q, X

pt, In

v, A

fish, M

fish, R

fish, [N

FW

, S

bird

, Lb

irdM

].

score #52:

certainty #52:


©20

06 H

GM

Gui

debo

okP

age

3/4

Hyd

roge

omor

phic

Ass

essm

ent G

uide

book

for T

idal

Wet

land

s of

the

Ore

gon

Coa

st, P

art 1

– A

ugus

t 200

6A

ppen

dix

A. D

ata

For

m B

2

cod

e in

dic

ato

r sc

ore

g

uid

ance

53

. E

xits

N

um

ber

of

inte

rnal

cha

nnel

exi

ts.

Co

un

t th

ese

usi

ng

a 1

:24

00

0 a

eria

l p

ho

tog

rap

h a

nd

en

ter

in

the

bo

tto

m b

ox

(“d

atu

m”)

in

th

e n

ext

colu

mn

.

Then

in t

he

top r

ow

of

the

rele

van

t ta

ble

bel

ow

(A

or

B),

fin

d

the

wet

land e

dge

length

. I

n t

hat

colu

mn

fin

d t

he

num

ber

of

chan

nel

exi

ts t

his

wet

land h

as.

Then

look a

long t

hat

row

to

the

last

colu

mn

for

the

resu

ltin

g s

core

. A

. W

etla

nd

s on

silt

, cla

y, o

r m

uck

sub

stra

te:

len

gth

of

exte

rnal

wet

ed

ge

(ft)

<1

000’

10

00-3

400’

>3

400’

sco

re

0 e

xit

s ts

0 e

xi

0 e

xit

s 0.

01

1

1-2

1-3

0.25

2

3

-5

-6

40.

50

3-4

1

0

2

6-

7-1

0.75

>

4

10

5

>

>1

1.00

B

. W

etla

nds

on s

and

sub

stra

te:

exit

s sc

ore

0

0.01

1

0.50

>

1

1.00

sc

ore

#53

:

ce

rtai

nty

#53

:

d

atu

m #

53:

Exi

ts =

wher

e in

tern

al c

han

nel

s fl

ow

in

to u

nveg

etat

ed w

ater

s o

r ti

def

lats

ou

tsid

e o

f th

e w

etla

nd

.

Ext

erna

l wet

edg

e le

ngth

is

mea

sure

d a

s th

e w

etla

nd’s

edg

e w

ith u

nveg

etat

ed w

ater

or

tidef

lat

at l

ow

tid

e.

For

chan

nel

s th

at c

on

nec

t at

bo

th e

nd

s to

a t

idef

lat

or

un

veg

etat

ed b

ay o

r ri

ver

, co

un

t both

en

ds

as e

xit

s.

Do n

ot

coun

t co

nst

ruct

ed

dra

inag

e d

itch

es.

IM

PO

RT

AN

T:

The

num

ber

of

exit

s is

str

ongly

rel

ated

to

mar

sh s

ize,

subst

rate

type,

and H

GM

subcl

ass—

som

etim

es

even

mo

re t

han

to

mar

sh d

istu

rban

ce. S

ee n

ote

fo

r #

52

, ab

ov

e.

If n

o a

cces

s to

aer

ial

ph

oto

gra

ph

s, a

ttem

pt

to e

stim

ate

bu

t sc

ore

cer

tain

ty “

0.0

1”.

U

sed

fo

r: A

Pro

d, W

Q, X

pt,

In

v, A

fish

, M

fish

, R

fish

, [N

FW

, S

bir

d, L

bir

dM

].

sco

re #

53:

cert

ain

ty #

53:

dat

um

#53

:


©2006 H

GM

GuidebookP

age 4/4H

ydrogeomorphic A

ssessment G



oast, Part 1 – A

ugust 2006A

ppendix A. D

ata Form

B2

cod

e in

dicato

r sco

re g

uid

ance

54. Ju

ncM

ax N

um

ber o

f intern

al channel junctions. C

ount th

ese along th

e single lo

ngest in

ternal ch

annel, u

sing a

1:2

40

00

scale aerial ph

oto

grap

h, an

d en

ter in th

e bottom b

ox

(“datu

m”) in

the n

ext co

lum

n.

Th

en in

top

row

of th

e relevan

t table b

elow

(A o

r B), fin

d th

e w

etland area. In

that co

lum

n fin

d th

e nu

mb

er of ch

ann

el junctions th

is wetlan

d h

as. Then

loo

k in

along th

at row

for

the last co

lum

n fo

r the resu

lting sco

re. A

. Wetlan

ds o

n silt, clay, or m

uck su

bstrate:

wetlan

d area (acres)

< 8 8-30

>30

sc

ore

0 jcts

0 jc

0 jc

0ts

ts .01

1

1

01-4

.50

2

-3

0.5

-7

75 >

1

>3

1.

>8

00

B. W

etlands o

n sand su

bstrate:

jun

ction

s sco

re 0

0.01 1

0.50 >

1

1.00

sco

re #54:

certain

ty #54:

d

atum

#54:

Junctions = v

isible co

nflu

ences b

etween

two in

ternal tid

al ch

annels reg

ardless o

f their relativ

e sizes. D

o n

ot co

un

t con

structed

drain

age d

itches.

Important: T

he n

um

ber o

f chan

nel ju

nctio

ns is stro

ngly

related

to m

arsh size, su

bstrat e ty

pe, an

d H

GM

subclass –

so

metim

es even

mo

re than

to m

arsh d

isturb

ance. S

ee no

te fo

r #5

2, ab

ov

e. If n

o access to

aerial ph

oto

grap

hs, attem

pt to

estimate b

ut

score certain

ty “0

.01”.

Used

for: A

Pro

d, W

Q, X

pt, In

v, A

fish, M

fish, R

fish, [N

FW

, S

bird

, Lb

irdM

].

55. F

reshS

po

t Internal freshw

ater. A

t a giv

en p

oin

t in tim

e, the m

axim

um

differen

ce betw

een

salinity

in u

nco

nfin

ed w

aters with

in th

e wetlan

d v

s. outsid

e th

e wetlan

d is:

d

ifference

score

in0.

ternal is <

10 p

pt fresh

er, or is m

ore salin

e 01

intern

al is 10-2

0 p

pt fresh

er 0.50

intern

al is >20 p

pt fresh

er 1.00

sco

re #5

5:

certain

ty #

55

:

Measu

re salinity

from

tidal w

ater (intern

al chan

nel o

r pool),

preferab

ly aro

un

d th

e time o

f low

tide, an

d su

btract fro

m

salinity

measu

red (alm

ost) sim

ult an

eously

in th

e adjo

inin

g

bay

or riv

er. If po

ssible, rep

e at du

ring

oth

er season

s and

use

the g

reatest differen

tial, which

often

is in m

id-su

mm

er. Do

no

t measu

re if any

rainfall h

as occu

rred in

last 24

ho

urs.

If no

access to a refracto

meter, attem

pt to

categorize b

ased o

n

any o

bserv

ed so

urces o

f freshw

ater input, b

ut sco

re certainty

“0

.01

”. U

sed fo

r: AP

rod

, Afish

, NF

W, D

ux

, Lb

irdM

, [WQ

, Xp

t, In

v].

score #54:

certainty #54:

datu

m #54:

score #55:

certainty #55:


Data Form C. Rapid Indicators of the Values of Functions

Logs large enough to be elevatedsubstantially above the surfaceprovide perches for birds thatforage in tidal marshes.

This optional form for assessing values offunctions is perhaps the most time-consum-ing and requires the most thought and back-ground investigation. The required informa-tion often will not exist for a particular siteand may be unobtainable in the short-term.Nonetheless, values of functions are impor-tant in assessing fairly the overall importanceof particular tidal wetlands. Much of theform can be completed in the office and byconsulting other resource professionals andlocal citizens. It is best to complete this formafter assessing functions with forms B1 andB2. Note that the form is organized aroundfunctions, with one set of questions for eachof the 12 tidal wetland functions (in a fewcases, multiple functions are grouped). For

each row, place a check mark in whichevercolumn seems to better reflect the wetlandyou’re assessing. Alternatively, you mayscore each value indicator on a scale of 0(lowest value) to 1.0 (highest value) andplace the score in the middle column of eachrow. If some of the requested information isnot available, proceed with other items in theassessment. Then copy your data to theaccompanying spreadsheet. If you wish, youmay assign weights to each row, but there isno defensible way of mathematically com-bining the scores for individual values intoan overall value score for each function (i.e.,no total “values” scoring models). Note thatthese are proscriptive as well as descriptiveevaluations–designed to help prioritize aswell as describe.

Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 – August 2006Appendix A. Data Form C, Intro.

©2006 HGM Guidebook

64 Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 – August 2006Appendix A

Primary Production and Exporting Aboveground Production highest function value suggested

score (0 to 1)

lowest function value

___ The wetland’s tidal marsh plants are extensively and sustainably grazed, and livestock are an important part of the local economy.

#101: ___ The wetland currently is not grazed and, due to wetness or its location, has little potential as pasture.

___ The wetland’s estuary has not experienced major die-offs of marine animals as a result of diminished dissolved oxygen.

#102: ___ The wetland’s estuary has experienced frequent and major die-offs of marine animals as a result of diminished dissolved oxygen, and the wetland is near the estuary mouth or other areas where this has occurred.

___ Uplands in this estuary, especially those closest to the water, are largely devoid of vegetation, e.g., sand dunes, pavement.

#103: ___ Uplands in this estuary are completely vegetated.

___ The site is one of only a few, or is one of the largest ones, of its subclass* in this estuary that supports and exports primary production to at least this degree.

#104: ___ Sites of this subclass and size that support and/or export primary production to this degree are relatively abundant in this estuary.

___ Other factors suggest that primary production specifically from this wetland is of unusually great importance to food webs located in the wetland or in receiving waters of the adjoining estuary or river. Explain:

#105: ___ Other factors suggest that primary production specifically from this wetland is not especially important to food webs located in the wetland or in receiving waters of the adjoining estuary or river. Explain:

* Tidal wetlands are provisionally labeled by their HGM subclasses in maps on the accompanying DVD.

Hydrogeomorphic Assessment Guidebook for Tidal Wetlands of the Oregon Coast, Part 1 – August 2006Appendix A. Data Form C

©2006 HGM GuidebookPage 1/8


Maintaining Element Cycling Rates and Pollutant Processing and Stabilizing Sediment highest function value suggested

score: lowest function value

opportunity to perform these functions: ___ Element inputs to the wetland may be relatively large as suggested by a score of 1.00 for items NutrIn, ChemIn, BuffAlt, and/or SedShed in the accompanying spreadsheet.

#106: ___ Element inputs to the wetland may be relatively small as suggested by a score of 0.01 for NutrIn, ChemIn, BuffAlt, and/or SedShed.

___ Large populations of salmon spawn very near the wetland.

#107: ___ Populations of spawning salmon are absent from this river basin.

___ Substantial volumes of woody and other organic matter enter the river or estuary a short distance upriver from the wetland as a result of recent fires, logging, or other factors.

#108: ___ Inputs of woody and other organic matter to the wetland are probably at or below historical (pre-settlement) rates.

___ Validated computer models of watershed processes indicate major net influx of sediments, nutrients, or metals to this estuary and wetland.

#109: ___ Validated computer models of watershed processes indicate no major delivery of sediments, nutrients, or metals to this estuary or wetland.

significance of this wetland (assuming these functions occur): ___ The site is near the estuary’s main head of tide.

#110: ___ The site is near the estuary mouth (where its individual effect, if any, may be dwarfed by marine circulation).

___ Rapid sedimentation and shoaling near the mouth of this estuary is a major concern and expense and/or the estuary is regularly dredged.

#111: ___ Sedimentation and shoaling near the mouth of this estuary are not a major concern or expense; no dredging occurs.

___ The wetland’s estuary has experienced frequent and major die-offs of marine animals as a result of diminished dissolved oxygen. The wetland is capable of processing internally much of the carbon it produces or imports, and thus avoids contributing to this problem. The wetland also is near the estuary mouth or other areas where severe oxygen deficits have occurred.

#112: ___ The wetland’s estuary has not experienced major die-offs of marine animals as a result of diminished dissolved oxygen.

___ The wetland is one of only a few of its subclass and size in this estuary that may stabilize sediments, remove nitrogen, and/or process carbon & pollutants to this or greater degree.

#113: ___ Wetlands of this subclass and size, that remove nitrogen or process carbon & pollutants to this or greater degree, are abundant in this estuary.

___ Other factors suggest that element cycling and removal functions of this wetland are of unusually great importance to biological or human resources in the wetland or in receiving waters of the estuary or river. Explain:

#114: ___ Other factors suggest that element cycling and removal functions of this wetland are not atypically important to biological or human resources in the wetland or in receiving waters of the estuary or river. Explain:




Maintaining Invertebrate Habitat highest function value suggested


___ This estuary ranks as one of the best for revenue and/or jobs from harvesting of crabs and other native mobile invertebrates.

#115: ___ This estuary supports little or no revenue and/or jobs from harvesting of native crabs and other native mobile invertebrates.

___ The wetland is one of a very few known on the Oregon coast known to be used by a particular native invertebrate species, and it otherwise supports a normal assemblage of invertebrates..

#116: ___ All invertebrate species known from this wetland are widespread in tidal wetlands of the Oregon coast.

___A large portion of the uplands and deeper waters near this wetland have very limited capacity to support invertebrates, e.g., largely devegetated, chemical contamination, frequent soil or sediment disturbance.

#117: ___ Upland and deepwater areas near this wetland have considerable capacity to support invertebrates, e.g., land cover is mostly unaltered, sedimentation is normal, there is little or no chemical contamination.

___ The site is one of only a few, or is one of the largest ones, of its subclass in this estuary that support native invertebrates to this or greater degree.

#118: ___ Sites of this subclass and size that support native invertebrates to this or greater degree are relatively abundant in this estuary.

___ Other factors suggest that invertebrate species or densities produced at this site are of unusually great importance to food webs or ecological processes in the wetland or its estuary. Explain:

#119: ___ Other factors suggest that invertebrate species or densities produced at this site are not atypically important to food webs or ecological processes in the wetland or its estuary. Explain:




Maintaining Anadromous Fish highest function value suggested


___ One or more federally-listed anadromous fish species or subpopulations are known to use this particular wetland frequently and extensively during critical periods.

#120: ___ No federally-listed anadromous fish species (or recognized subpopulation) is known from the wetland or nearby waters.

___ In the past, considerable funds have been expended to restore or enhance this particular wetland specifically for (among perhaps many objectives) anadromous fish.

#121: ___ In the past, no funds have been expended to restore or enhance this particular wetland specifically for anadromous fish.

___ The site is one of only a few, or is one of the largest ones, of its subclass and size in this estuary that supports anadromous fish to this or greater degree.

#122: ___ Sites of this subclass and size that support anadromous fish to this or greater degree are relatively abundant in this estuary.

Maintaining Habitat for Resident Fish and Maintaining Habitat for Visiting Marine Fish highest function value suggested


___ This estuary ranks as one of the best for revenue and/or jobs from harvesting of resident and visiting marine fish.

#123: ___ This estuary supports little or no revenue and/or jobs from harvesting of resident and visiting marine fish.

___ The wetland is one of a very few on the Oregon coast known to be used by a particular non-anadromous fish.

#124: ___ All non-anadromous fish species known from this wetland are widespread in tidal wetlands of the Oregon coast.

___ The wetland or closely connected waters provide some of the most consistently productive fishing for native tidal marsh fish species and/or marine species on the Oregon coast.

#125: ___ Site does not provide atypically productive fishing for any native tidal marsh fish species or marine species on the Oregon coast.

___ The site is one of only a few, or is one of the largest ones, of its subclass in this estuary that supports non-anadromous fish to at least this degree.

#126: ___ Sites of this subclass and size that support non-anadromous fish to this degree or greater are relatively abundant in this estuary.

___ Other factors suggest that non-anadromous fish species or densities of native mobile invertebrates inhabiting the wetland are of unusually great importance to food webs or ecological processes in the wetland or closely connected waters. Explain:

#127: ___ Other factors suggest that non-anadromous fish species or densities of native mobile invertebrates inhabiting the wetland are not atypically important to food webs or ecological processes in the wetland or closely connected waters. Explain:




Maintaining Habitat for Ducks and Geese and Maintaining Habitat for Shorebirds Some potential sources of data:

www.ohjv.org/pdfs/northern_oregon_coast.pdf www.ohjv.org/pdfs/southern_oregon_coast.pdf www.oregoniba.org/ www.oregoniba.org/links.htm www.wetlandsconservancy.org/oregons_greatest.html audubon2.org/webapp/watchlist/viewWatchlist.jsp

highest function value suggested


___ The wetland is consistently and/or extensively used by many waterbird species that are regionally uncommon and/or have declining populations in the Pacific Northwest.

#128: ___ All waterbird species that regularly use the wetland are common and widespread over most of the Oregon coast, and the wetland is distant from areas used by waterbird species that are regionally uncommon and/or have declining populations in the Pacific Northwest.

___ The wetland is one of a very few that contains habitat conditions identified as optimal for one or more particularly rare and/or regionally declining waterbird species.

#129: ___ The wetland does not contain habitat suitable for any particularly rare and/or regionally declining waterbird species, nor is it near such areas.

___ The wetland or its estuary was identified as being of exceptional importance for waterbirds by the Oregon Wetland Joint Venture Plan, North American Waterfowl Management Plan, or the North American Shorebird Plan.

#130: ___ Neither the wetland nor its estuary was identified as being of exceptional importance for waterbirds by the named documents, and is distant from such areas.

___ The wetland or its estuary is registered or has been formally proposed as an Important Bird Area (IBA) of the National Audubon Society.

#131: ___ The wetland is not within an estuary that is registered or formally proposed as an IBA, and is distant from such areas.

___ Other factors suggest that waterbird species or densities at this site are of unusually great importance to food webs or ecological processes in the wetland or estuary.

#132: ___ Other factors suggest that waterbird species or densities at this site are not atypically important to food webs or ecological processes in the wetland or estuary.

___ In the past, considerable funds have been expended to restore or protect specifically the suitability of this particular wetland for (among perhaps many objectives) waterbird habitat.

#133: ___ In the past, no funds have been expended to restore or protect specifically the suitability of this particular wetland for waterbird habitat.

___ The site is one of only a few, or is one of the largest ones, of its subclass in this vicinity that support waterbirds to this degree.

#134: ___ Sites of this subclass and size that support waterbirds to at least this degree are relatively abundant in this estuary and elsewhere on the Oregon coast.




Maintaining Habitat for Native LandBirds, Small Mammals, and Their Predators and Maintaining Habitat for Nekton-feeding Birds Some potential sources of data:

oregonstate.edu/ornhic/ www.oregoniba.org/ www.oregoniba.org/links.htm audubon2.org/webapp/watchlist/viewWatchlist.jsp



___ The wetland is consistently and/or extensively used by native land bird or mammal species that are listed as Threatened, Endangered, or Sensitive, or are recognized as conservation priority species or communities by Partners-in-Flight or the Oregon Natural Heritage Program.

#135: ___ No such species or communities are present in the wetland or nearby parts of the estuary.

__ Other native land bird or mammal species that are regionally uncommon and/or have declining populations in the Pacific Northwest are consistently and/or extensively present in the wetland.

#136: ___ All native land bird or mammal species that use this wetland occur widely on the Oregon coast and none are known to be declining at a regional scale.

___The wetland is one of a very few that contains habitat conditions identified as optimal for one or more particularly rare and/or regionally declining wetland-associated bird species (other than waterbirds).

#137: ___ The wetland does not contain habitat suitable for any particularly rare and/or regionally declining, wetland-associated bird species (excluding waterbird species).

___ Other factors suggest native land bird or mammal species or densities at this site are of unusually great importance to food webs or ecological processes in the wetland or its estuary.

#138: ___ Other factors suggest that native land bird or mammal species or densities at this site are not atypically important to food webs or ecological processes in the wetland or its estuary.

___ In the past, considerable funds have been expended to restore specifically the suitability of this particular site for (among perhaps many objectives) wetland-associated native land birds or mammals.

#139: ___ In the past, no funds have been expended to restore specifically the suitability of this particular site for wetland-associated native land bird or mammal species.

___ The site is one of only a few, or is one of the largest ones, of its subclass in this vicinity that support wetland-associated native land bird or mammal species to this degree.

#140: ___ Sites of this subclass and size that support native land bird or mammal species to this degree are relatively abundant both locally and regionally.




Maintaining Natural Botanical Conditions Some potential sources of data:

www.oregonstate.edu/ornhic www.npsoregon.org cladonia.nacse.org/platlas/jclass/OPAJava20.htm ocid.nacse.org/cgi-bin/qml/herbarium/plants/vherb.qml



___ Site contains many native plant species or associations that are uncommon and/or have declining populations in Oregon coastal tidelands. This may include, but is not limited to, species categorized as G1, G2, S1, or S2 by the Oregon Natural Heritage Program.

#141: ___ All plant species and associations at this site also occur widely in Oregon coastal tidelands, and none have been documented to be declining in the ecoregion.

___ Site is one of a very few that contains habitat conditions identified as optimal for one or more particularly rare and/or regionally declining native plant species or associations. This includes, for example, sites with extensive woody vegetation (especially Sitka spruce) that are regularly flooded by tides. In Oregon this is a relatively rare type of wetland that has declined dramatically.

#142: ___ Site does not contain habitat suitable for any particularly rare and/or regionally declining native plant species or association.

___ Other factors suggest that native plants at this site are of unusually great importance to food webs or ecological processes located onsite or in the region generally.

#143: ___ Other factors suggest that native plants at this site are not atypically important to food webs or ecological processes located onsite or in the region generally.

___ The site is one of only a few, or is one of the largest ones, of its subclass in this estuary that support native tidal vegetation to this degree.

#144: ___ Sites of this subclass and size that support characteristic vegetation to this degree are relatively abundant both in this estuary and regionally.

___ In the past, considerable funds have been expended to restore specifically the suitability of this particular site for unusual or characteristic native plant species or associations.

#145: ___ In the past, no funds have been expended to restore specifically the suitability of this particular site for native plant species.




Other Factors Potentially Relating to Value or Concern A potential source of data: www.coastalatlas.net/metadata/TidalWetlandsofOregonsCoastalWatersheds,Scranton,2004.htm highest concern suggested

score: lowest concern

__ Loss of tidal wetlands has been greater in this estuary than in any other on the Oregon Coast.

#146: __ Loss of tidal wetlands has been less in this estuary than in any other on the Oregon Coast.

__ This wetland is the only one of its HGM subclass in this estuary.

#147: __ This wetland belongs to an HGM subclass that is the most common one in this estuary.

__ The wetland belongs to an HGM subclass that has experienced the most losses of any tidal HGM subclass in this estuary.

#148: __ The wetland belongs to an HGM subclass that has experienced the lowest losses (or greatest gain) of any tidal HGM subclass in this estuary.

__ The entire wetland is designated as a Hazardous Waste Site.

#149: ___ No portion of the wetland or its immediate tributaries is designated as a Hazardous Waste Site.

__ Much of the wetland is known to contain artifacts of high archaeological importance.

#150: __ None of the wetland is known to contain artifacts of high archaeological importance.

__ The wetland is visited by many people engaging in activities that are compatible (in moderation) with its natural functions, e.g., kayaking, educational tours, hunting, fishing, birding.

#151: __ The wetland is almost never visited, or is visited to such a large degree that some functions are impaired.




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Appendix B. Abbreviations Used In This Document

Function abbreviations

used in this document

description

Afish Maintain Habitat for Anadromous Fish

AProd Produce Aboveground Organic Matter

BotC Maintain Natural Botanical Conditions

Dux Maintain Habitat for Ducks and Geese

Inv Maintain Habitat for Native Invertebrates

LbirdM Maintain Habitat for Native Landbirds, Small Mammals, & Their Predators

Mfish Maintain Habitat for Visiting Marine Fish

NFW Maintain Habitat for Nekton-feeding Birds

RA Assessment of Risks to Wetland Integrity & Sustainability

Rfish Maintain Habitat for Other Visiting and Resident Fish

Sbird Maintain Habitat for Shorebirds

WI Wetland Integrity

WQ Maintain Element Cycling Rates and Pollutant Processing; Stabilize Sediment

Xpt Export Aboveground Plant & Animal Production

Appendix B


The abbreviations of the indicator variables are listed in Appendix A and in the left-hand columns ofForms B1 and B2. In the following formulas, “*” denotes multiplication. Items within parenthesesare averaged (AVG) or their maximum (MAX) is taken. Calculations involving items within brack-ets are performed only after calculations within parentheses contained within those brackets areperformed. Reasons for the particular choices of combination rules are given in Part 2 of thisguidebook. The accompanying Excel™ spreadsheet will produce the same scores, but in somecases slightly different formulas were embedded for more efficient data processing.

Scoring Models

Produce Aboveground Organic Matter (AProd)NutrIn + [(AVG: Fresh, FreshSpot) + Pform – Bare – SoilX – Shade

Export Aboveground Plant & Animal Production (Xpt)AProd + [AVG: BlindL, Jcts, Exits, Flood, TribL, (1- Width)]

Maintain Element Cycling Rates and Pollutant Processing; Stabilize Sediment (WQ)AProd + (AVG: BlindL, Jcts, Exits, Flood) + Width + UpEdge + SoilFine –[AVG: TranAng, (1-RatioC), Fetch, SoilX]

Maintain Habitat for Native Invertebrates (Inv)AProd + (AVG: BlindL, Jcts, Exits) + (AVG: Pform, FormDiv, SppPerQd) + (MAX: Eelg, Alder) +(AVG: Fetch, LWDchan, LWDline, Pannes, UpEdge) + (AVG: Fresh, FreshSpot, TribL) – Invas –ChemIn – SedShed – Instabil – (1-Island)

Maintain Habitat for Anadromous Fish (Afish)(AVG: Flood, SeaJoin) * {AVG [Inv, Estu%WL, (AVG: BlindL, Jcts, Exits), (1-ChemIn)} +(MAX: Eelg, LWDchan) + (MAX: TribL, Fresh, FreshSpot) + EstuSal + ShadeLM

Maintain Habitat for Marine Fish (Mfish)(AVG: Flood, SeaJoin) * {AVG [Inv, Eelg, (AVG: BlindL, Jcts, Exits), (1-ChemIn)]}

Maintain Habitat for Other Visiting and Resident Fish (Rfish)Flood * + [(MAX: LWDchan, Eelg) + (MAX: TribL, Fresh, FreshSpot) + Pannes]

Maintain Habitat for Nekton-feeding Wildlife (NFW)(MAX: Rfish, Afish, Mfish) + (AVG: TribL, BlindL, Exits, Jcts) + (MAX: Bare, MudW, Pannes) +(AVG: WetField%, Fresh, FreshSpot) + [AVG: BuffCov, (1-FootVis), (1-Boats)]

Maintain Habitat for Ducks and Geese (Dux)(AVG: BlindL, Exits, Jcts, Flood) + (AVG: Eelg, Bare, MudW, NutrIn, Pform) +(AVG: Fresh, FreshSpot, TribL) + WetField% + (1 – Fetch) + {[MAX: (Width, 1 - Island)] –[AVG: FootVis, Boats]}

Appendix C. Scoring Models and Scales Used to Assess theFunctions

Appendix C


Maintain Habitat for Shorebirds (Sbird)Inv + (MAX: Bare, Pannes, Flood) + [(MAX: Roost, MudW, WetField%) – FootVis –(AVG: FormDiv, UpEdge) – (1-Width)

Maintain Habitat for Native Landbirds, Small Mammals, & Their Predators (LBM)[UpEdge + (AVG: Pform, BuffCov) + (AVG: SppPerQd, Inv) + (AVG: TribL, FreshW, FreshSpot) +(AVG: LWDmarsh, LWDline) – HomeDis – RoadX – Flood] * Island

Maintain Habitat for Native Botanical ConditionsSppPerQd – NNgt20

Wetland Integrity IndexAVG: Ratio C, SpDeficit, DomDef, NNdef, AnnDef, TapPCdef, StolPCdef, TuftPCdef

Appendix C


Scales Used for Computed Indicators RatioC:

mean absolute difference score <40 1.00

40-59 0.80 60-69 0.60 70-99 0.40

100-250 0.20 >250 0.01

SpPerQd:

mean number per quad score <2 0.01

2.1-2.6 0.10 2.7-3.2 0.20 3.3-3.8 0.30 3.9-4.2 0.50 4.3-4.8 0.60 4.9-5.4 0.80 5.5-5.8 0.90

>5.8 1.00 SpDeficit:

adjusted difference score <5.00 0.01

5.00-5.56 0.25 5.57-6.06 0.50 6.07-6.82 0.75

>6.82 1.00 AllPC90:

proportion score >0.66 (>13 quads) 0.01

0.38-0.66 (8-13 quads) 0.10 0.34-0.37 (7 quads) 0.20

0.24-0.33 (5-6 quads) 0.40 0.16-0.23 (3-4 quads) 0.50

0.10-0.15 (2 quads) 0.60 0.06-0.09 (1 quad) 0.80

<0.06 (no quads) 1.00 DomDef:

adjusted difference score > 1.11 0.01

1.01-1.11 0.25 0.94-1.00 0.50 0.82-0.93 0.75

<0.82 1.00

NN20PC:

proportion score >0.95 (>19 quads) 0.01

0.70-0.94 (14-19quads) 0.10 0.53-0.69 (11-13 quads) 0.20

0.35-0.52 (5-6 quads) 0.40 0.20-0.34 (4 quads) 0.50 0.11-0.19 (3 quads) 0.60

0.05-0.11 (1-2 quads) 0.80 <0.05 (none) 1.00

NNdef:

adjusted difference score >1.21 0.01

1.04-1.21 0.25 0.94-1.03 0.50 0.80-0.93 0.75

<0.80 1.00 AnnDef:

adjusted difference score >1.05 0.01

0.96-1.05 0.25 0.80-0.95 0.50 0.72-0.79 0.75

<0.72 1.00 TapPCdef:

adjusted difference score <5.05 0.01

5.05-6.28 0.25 6.28-7.47 0.50

7.48-11.13 0.75 >11.13 1.00

StolPCdef:

adjusted difference score >98 0.01

93-98 0.25 84-92 0.50 74-83 0.75

<74 1.00 TuftPCdef:

adjusted difference score <22 0.01

22-24 0.25 25-27 0.50 28-32 0.75

>32 1.00

Appendix C


Appendix D. Glossary

Assessment unit: (also called “site” or “assessment area”) the wetland area that is being examined;may include all or part of an entire marsh, wetland, or wetland polygon. If the wetland containsmultiple HGM subclasses, it is classified according to whichever subclass comprises the largestarea. If one of the component subclasses comprises more than 20% of the area, that area is assessedas a separate unit.

Calibration: the process of standardizing (scaling) data to a specific numeric range (scale) bydividing by a constant, such as the maximum value in a data set.

Channel: a distinct semi-linear depression with a definable outlet and with identifiable bank edgesthat have been shaped by flowing water; includes manmade ditches and swales that may flow onlyintermittently, and includes both tidal channels and non-tidal (stream or river) channels.

Channel pool: an unvegetated, intermittently-isolated depression (of least 2m2) in a channelbottom, that fails to empty completely during low tide. Salinity is similar to that of the channelnetwork to which it connects during high tide. Compare with panne and fresh pool.

Ecoregion: a large geographic area delimited by its relative homogeneity of climate, topography,and land cover.

External edge: the interface between vegetation at the lowest point in the low marsh (i.e., the outeredge of the marsh) and unvegetated tidal or subtidal habitat (the receiving waters).

Fetch: the distance over water in which waves are generated by a wind having a constant directionand speed. Generally considered synonymous with the maximum open water distance in thedirection from which the strongest and most constant winds blow.

Flood tide: the rising tide that occurs twice daily in Oregon.

Fresh pool: an unvegetated, apparently-isolated depression of least 2m2 in the surface of the highmarsh plain, of natural or artificial origin, that contains surface water whose salinity is less than thatof nearby channels. Fed mainly by rain and/or groundwater discharge. Adjoining vegetation is nothalophytic. Compare with panne and channel pool.

Function: what a site does; especially, the hydrologic, geochemical, and biological processes it(potentially) performs without human assistance. Functions support ecosystems and economies.

Function capacity: an estimate of the rate or magnitude (i.e., effectiveness, sensu Adamus 1983)an assessment site and its supporting landscape perform a specified function, relative to otherwetland sites in its subclass. Termed “potential functional performance” by Hruby et al. (1999).

HGM: see Hydrogeomorphic.

Appendix D


High marsh: a wetland that is inundated by tidal surface water at least once annually but not daily.Synonymous with supratidal marsh and with the MSH (marine-sourced high) subclass of theOregon HGM classification scheme.

High tide: as used in this guidebook, the maximum height reached by the two rising tides thatoccur daily at a given location. Mean high tide is the average of all daily high tides at the locationover the span of a month.

Highest functioning standard: a site or small group of sites that received the highest score for aspecified function, among a much larger group of sites similarly assessed.

Hydrogeomorphic (HGM): pertaining to water, geologic setting, and/or morphological (landform)features.

Hydrogeomorphic (HGM) approach: a framework (Smith et al. 1995) for the regionaldevelopment of rapid assessment methods that features: (a) preclassification of wetland sitesaccording to their likely water sources and flow direction; (b) use of rapid indicators of wetlandfunctions, based on regional literature review and expert opinion; (c) calibration of the indicators ata series of regional reference sites prior to methods development; and (d) specification of rules(scoring models) to combine the calibrated data for individual indicators into scores representingrelative capacity of each of a site’s wetland functions.

Hydrogeomorphic (HGM) Classification: the national classification of wetlands based ongeomorphic setting, water source and transport, and hydrodynamics, as proposed by Brinson (1993).Use of a regionalization of this approach for Oregon (Adamus 2001b) is required by the OregonDepartment of State Lands in applications for Removal-Fill permits and for local WetlandsInventories.

HGM subclass: one of 13 types of wetlands, defined by hydrological and geomorphiccharacteristics, that occur in Oregon, as described by Adamus (2001b). Three of these subclassesare the subject of this guidebook.

Indicator: characteristics or variables that are relatively easy to observe and (in this guidebook) arebelieved to correlate with (but are not necessarily causally linked with) processes that supportspecific wetland or riparian functions. Not limited to “field indicators” used to delineate wetlands.

Integrity: see Wetland Integrity.

Internal tidal channel: a low-gradient tidal channel that is surrounded by marsh, is much narrowerthan the marsh, and may not extend into uplands beyond the marsh.

Inundated, Inundation: covered wholly or partly with surface water; the water may come directlyfrom precipitation, subsurface water table rise, runoff, tides, or channel flow.

Least-altered standard: a site or small group of sites that, by consensus, are the least likely amongmany in a region to have been exposed to lasting or chronically serious alterations as a result ofhuman activities.

Appendix D


Low marsh: a marsh that is inundated twice daily by the tide. Synonymous with intertidal marsh.Includes the MSL (marine-sourced low) and RS (river-sourced) subclasses of the Oregon HGMclassification scheme.

Low tide: as used in this guidebook, the lowest level reached by the two falling (ebbing) tides thatoccur daily at a given location. Mean low tide is the average of all daily low tides at the locationover the span of a month.

Model, scoring: a mathematical device (formula, equation) for combining numeric estimates ofindicators, in a manner thought to represent function or some other attribute of a site.

MSH: see High Marsh.

MSL: see Low Marsh. (Also an abbreviation for Mean Sea Level, but not used in that context inthis guidebook.)

Neap tide: a tide occurring at or near the time of half-moons. The neap tide range is usually 10%to 30% less than the mean tidal range.

Non-native: species not present in Oregon tidal marshes during pre-settlement times, but currentlyoccurring as the result of natural or human-aided establishment. Used synonymously with “exotic”or “alien” species. Includes a few species, e.g., Phalaris arundinacea, that were historically presentbut whose range and regional dominance has expanded tremendously.

Panne (also spelled pan): a mostly-unvegetated, apparently isolated, generally circular or ovalmicrodepression in the surface of the high or low marsh plain, generally at least 2m2 in area,sometimes caused by shading and tidal scouring around deposited logs and driftwood, or by relictsof former channels or ditches. May or may not contain surface water; the salinity of any surfacewater is usually equal or greater than that of the nearest tidal channel. If vegetation is present, it isgenerally sparse and comprised mainly of halophytic species. Compare with fresh pool and channelpool.

Pannes are naturally-occurring shallowdepressions in themarsh surface thatoften have verydifferent salinity andvegetation.

Appendix D


Predominant, Predominating, Predominance: comprising the largest portion of space in thehorizontal dimension; need not comprise a majority of the space (i.e., 50% or any other threshold).

Quadrat: a square-shaped unit, generally a few meters or less per side, used to standardizesampling. Sometimes used synonymously with “plot.”

Reference site: an assessment site or unit that, together with others, is used to calibrate regionalscoring models of wetland function for the particular HGM subclass. Such sites are selected toencompass the expected natural and human variability among wetlands of their subclass in theregion. In the HGM method, altered sites are allowed to be reference sites (see Reference StandardSite).

Reference standard site: a reference site that, along with a very few others, is among the least-altered sites of its type in an ecoregion. Data from such sites may be used as the “gold standard”against which the performance of other wetlands (of the same subclass and ecoregion) may bejudged.

Risk (to wetland integrity): the probability that stressors may, over the short or long term, threaten awetland’s geomorphic and/or biological integrity, primarily as related to the magnitude and durationof the stressor rather than to the intrinsic sensitivity of the wetland.

Salt marsh: a tidal marsh that is predominantly influenced by marine-sourced waters.

Site: the tidal marsh assessment area or polygon. Tidal marshes do not always exist as highlydiscrete units in space and time.

Shrub: a woody plant that is between 6 and 20ft. tall; includes early stages of species thateventually grow to be trees.

Spring tide: a tide occurring at or near the time of new or full moon and that rises highest and fallslowest from the mean sea level.

Tidal amplitude: the difference in level between low tide and high tide on a given day.

Tidal range: the difference in level between all low and high tides at a specific location andaveraged over a long period, generally 18.6 years.

Tidal channel: a channel whose water is primarily from downgradient (subtidal) sources; the wateris transported into the tidal channel by tidal forces. Such channels are often “blind,” i.e., are notconnected to freshwater subsidiary tributaries that enter the marsh from its upland edge.

Tidal marsh: a wetland, usually with a predominance of emergent herbaceous vegetation, thatusually is inundated by the tide once or twice a month during spring high tides, and once annually atthe very least. Includes both low (intertidal) and high (supratidal) marsh. As used in this guide,includes tidal shrub and spruce wetlands, but not eelgrass beds. May have fresh, saline, or brackishsurface water.

Tidal prism: the difference in water volume between high and low tide.

Appendix D


Tidegate: a mechanical device placed in a dike or natural riverbank to block saltwater fromentering channels and lowlands behind the dike that otherwise would be flooded by high tide whileallowing fresh water to drain during low tide. Tidal fluctuations behind the point where it is placedare eliminated or muted. Tidegates may consist of a wooden or metal flap hinged on the top of adownstream end of a culvert. The tidegate is positioned so that a rising tide forces the gate againstthe culvert, preventing flooding inside the dike by the rising tide. Freshwater then backs up behindthe gate. On the ebb tide, the gate opens when the downstream level is lower than the freshwaterlevel, allowing drainage of the land or wetland behind the dike (Giannico & Souder 2004a, b).

Topographic map: a map showing elevations. Maps at a very coarse scale can be viewed online at:topozone.com .

Tree: for purposes of this guidebook, a woody plant taller than 20ft.

Tributaries: non-tidal freshwater subsidiary channels, that may or may not contain water year-round, and which traverse the marsh on their path into the mainstem estuarine channel or bay.

Upland: as used in this guidebook, any terrestrial area not exposed to tides. Includes freshwaterwetlands that are not so exposed, but which may remain inundated for long periods due to runofffrom the watershed. Often delimited by the transition from herbaceous marsh to closed-canopywoodland or sand dune, and sometimes by a line of weathered driftwood.

Values: as used in this guidebook, the economic, ecological, or social importance assigned afunction as a result of its opportunity to provide functions, goods, and services–and the significanceof these.

Variable: as used in this guidebook, a factor that determines wetland function; may or may not berelatively easy to measure (see Indicator).

Wetland integrity: the ability of a wetland to support and maintain: (a) dynamic hydrogeomorphicprocesses within the range found in wetlands that have experienced the least alteration by humans;and (b) a balanced, integrated, adaptive community of organisms having a species composition,diversity, and functional organization comparable to that found in relatively unaltered native habitatsof the region. That ability is also characterized as influenced by (and influencing) geomorphicprocesses. Together, these define the ability to support and maintain wetland complexity andcapacity for self-organization with respect to species composition, physical and chemicalcharacteristics, and functional processes. A wetland may be considered to have high integrity (orbe in “intact” condition) when all of its natural processes and parts are functioning within theirnatural ranges of variation. Integrity often is used synonymously with “naturalness,” although thelinkage between naturalness, wetland complexity, and wetland self-organizing capacity may notalways be clearly apparent. Estimates of a wetland’s integrity commonly are expressed by a singleword or score. Although indices for assessing biological integrity of Oregon streams have beentested and applied (Hughes et al. 2004), no such indices have yet been successfully tested forOregon wetlands.

Wrack: flotsam and other floating debris, e.g., seaweed, plant litter, trash. Often deposited by tidesalong the daily high tide level in a “wrack line.”

Appendix D

for additional copies of thisdocument, contact

Oregon Watershed Enhancement Board775 Summer Street, Suite 360

Salem, OR 97301-1290

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