DOC

BASELINE ASSESSMENT OF PHYSICAL HABITAT AND MACROINVERTEBRATES IN

By Beth Mills,2014-10-17 10:29
12 views 0
BASELINE ASSESSMENT OF PHYSICAL HABITAT AND MACROINVERTEBRATES IN

    BASELINE ASSESSMENT OF STREAM HABITAT AND MACROINVERTEBRATE COMMUNITIES IN AND ADJACENT TO THE DAMASCUS AREA URBAN GROWTH

    BOUNDARY EXPANSION, OREGON

    2006 FINAL REPORT

    Prepared by

    Michael B. Cole

    ABR, Inc.--Environmental Research & Services

    P.O. Box 249

    Forest Grove, Oregon 97116

    and

    Lori A. Hennings

    Metro

    600 NE Grand Ave.

    Portland, OR 97232-2736

ABR Draft Report UGB Expansion Baseline Invertebrates i

    EXECUTIVE SUMMARY

     Portland, Oregon’s Urban Growth Boundary (UGB) was expanded in 2003 by more than 12,000 acres in the Damascus area, representing the single largest expansion of the UGB since its establishment. The primary objective of this study was to characterize current benthic macroinvertebrate, water quality, and physical habitat conditions in streams occurring within and adjacent to the expansion area. A secondary objective of the study was to investigate the effects of forested buffers within the study area on macroinvertebrate communities.

     Macroinvertebrate communities, physical habitat, and water chemistry were sampled from 40 study reaches in and adjacent to the expansion area between September 29 and October 15, 2003, including six reaches on the Clackamas River and 34 reaches in smaller drainages, including Rock, Richardson, Noyer, NF Deep, Butler, and Kelly creeks.

     Macroinvertebrate data were analyzed using both multimetric and multivariate techniques. Riffle samples were analyzed using the Oregon Department of Environmental Quality’s ten-metric set and scoring criteria. Impairment levels were assigned to benthic communities from each reach based on these results. Multivariate ordination was used to examine the data for patterns in macroinvertebrate community composition, followed by correlation with environmental variables to detect relationships between macroinvertebrate community composition and physicochemical conditions. Study stream reaches encompassed a wide range of riparian and stream channel conditions. Riparian conditions varied widely, but on the four larger tributary systems: Rock, Richardson, Noyer, and NF Deep creeks, riparian zones were largely intact and often extended 50-100 m out from each bank, particularly in the lower reaches of these systems. Streams occurring within the study area ranged in size, gradient, substrate composition, and relative frequencies of different habitat types. Using the Rosgen Level II geomorphic classification system, a number of stream channel types occurred in the study area; the most common were B3 and G3 channels, with 11 of the of the former and 8 of the latter type occurring in the sample of 34 reaches.

    ABR Draft Report UGB Expansion Baseline Invertebrates i

    rdth- to 5-order reaches produced a 3-dimensional ordination that explained NMS of 3

    74% of the original variation among samples. Axis one accounted for 2/3 of that explained variation. Environmental variables significantly correlated with axis one included specific conductance and a number of land use/land cover variables. Land use land cover variables that were significantly correlated with NMS axis 1 were % forested area for 1500 m upstream at 50, 100, and 200-m wide, and numerous land use/cover variables at various widths extending the entire upstream length.

     Macroinvertebrate community conditions, as indicated by multimetric scores, ranged from 10 to 42 among sampled reaches. Communities in most reaches were classified as slightly or moderately impaired, as 13 reaches scored in the slightly impaired range and 17 reaches scored in the moderately impaired range. Six reaches scored in the severely impaired range, while only one reach, located in Richardson Creek, scored in the unimpaired range. Clackamas River reaches all scored as moderately impaired, ranging from 24 to 28.

     A distinct longitudinal trend occurred in four of the larger watersheds in the study area. The three Noyer Creek reaches were scored as slightly, moderately, and severely impaired from downstream to upstream. A similar longitudinal trend was observed among North Fork Deep Creek riffle sample scores, as scores increased from 10 (severely impaired) to 26 (moderately impaired) from upstream to downstream. Rock Creek, and to a lesser extent, Richardson Creek, also showed longitudinal trends of increasing multimetric scores from upstream to downstream.

     Macroinvertebrate impairment class was significantly related to several variables describing forested riparian conditions. Three of the six variables (those where land use percentages were calculated for the entire upstream distance) were significant at alpha = 0.01, while two of the remaining three (those buffered for 1500 m upstream) were significant at alpha = 0.05. Percent forested cover in a 200-m buffer was more significant than forested cover within 100 or 50-m buffers (alpha = 0.026, 0.046, 0.063). 20010050

     This study characterized baseline benthic biological conditions in streams occurring throughout the Damascus UGB expansion area. The data can be used to track changes over time in response to urbanization of the watershed, but only with adequate characterization of current spatial and temporal variability within the watershed.

    ABR Draft Report UGB Expansion Baseline Invertebrates ii

    TABLE OF CONTENTS

LIST OF FIGURES .................................................................................................................. iii

    LIST OF TABLES .................................................................................................................... iv

    ACKNOWLEDGMENTS ......................................................................................................... vi INTRODUCTION ......................................................................................................................1

    STUDY AREA ...........................................................................................................................2

    METHODS .................................................................................................................................3

    STUDY REACH SELECTION ...............................................................................................3 FIELD DATA COLLECTION ................................................................................................3 SAMPLE SORTING AND MACROINVERTEBRATE IDENTIFICATION ..........................6

    QUALITY ASSURANCE .......................................................................................................6 DATA ANALYSIS .................................................................................................................6

    Multivariate Pattern Analysis ..............................................................................................7

    Multimetric Analysis ............................................................................................................8 RESULTS ................................................................................................................................. 10

    DISCUSSION ........................................................................................................................... 13

    MONITORING STRATEGY .................................................................................................... 18 LITERATURE CITED ............................................................................................................. 20

    LIST OF FIGURES

    Figure 1. Location maps of 40 stream and river reaches sampled for macroinvertebrates, water

    quality, and physical habitat in and adjacent to the Damascus area urban growth boundary

    expansion, Clackamas County, Oregon, fall 2003. ............................................................. 32 Figure 2. NMS ordination biplot of macroinvertebrate samples collected from 34 stream reaches

    in and adjacent to the Damascus area urban growth boundary expansion, Oregon, fall 2003.

    Environmental variables that were significantly correlated (p < 0.01) with NMS axes Vector

    lines point in the direction that the stated variable increases; longer lines indicate a stronger

    correlation. ........................................................................................................................ 33

    Figure 3. NMS ordination biplots of macroinvertebrate samples collected from 19 moderate-

    gradient (>1.5%) stream reaches in and adjacent to the Damascus area urban growth

    boundary expansion, Oregon, fall 2003. Environmental variables that were significantly

    correlated (p < 0.01) with NMS axes Vector lines point in the direction that the stated

    variable increases; longer lines indicate a stronger correlation. .......................................... 34 Figure 4. NMS ordination biplot of macroinvertebrate samples collected from 19 moderate-

    gradient (>1.5%) stream reaches in and adjacent to the Damascus area urban growth

    boundary expansion, Oregon, fall 2003. The vector line represents the significance and

    direction of the correlation between Multimetric Scores and NMS axis 1........................... 35 Figure 5. Frequency of multimetric scores of macroinvertebrate communities sampled from 31

    stream reaches in and adjacent to the Damascus area urban growth boundary expansion,

    Oregon, fall 2003............................................................................................................... 36

    Figure 6. Macroinvertebrate community multimetric scores from the four Clackamas River

    tributaries occurring in and adjacent to the Damascus area urban growth boundary

    expansion, Clackamas County, Oregon, fall 2003. Scores from sample reaches are arranged

    ABR Draft Report UGB Expansion Baseline Invertebrates iii

    from downstream to upstream on each graph to illustrate longitudinal trends in community

    conditions on each system. ................................................................................................ 37

    Figure 7. Relationships between macroinvertebrate metrics (including Multimetric Scores) and

    specific conductance, the only field-measured environmental variable that was significantly rd correlated with metric scores calculated from macroinvertebrate samples collected from 3ththrough 5-order streams in and adjacent to the Damascus area urban growth boundary

    expansion, Clackamas County, Oregon, fall 2003. ............................................................. 38

    Figure 8. Relationships between Multimetric Scores and land use/cover variables that were rdsignificantly with these scores calculated from macroinvertebrate samples collected from 3 ththrough 5-order streams in and adjacent to the Damascus area urban growth boundary

    expansion, Clackamas County, Oregon, fall 2003. ............................................................. 39 Figure 9. Relationships between percent forested cover (using six different GIS buffer

    dimensions) and macroinvertebrate community impairment in stream reaches sampled for

    macroinvertebrates in and adjacent to the Damascus area urban growth boundary expansion,

    Clackamas County, Oregon, fall 2003. The first three buffer variables are percent forested

    area within the stated width for the entire upstream distance. One asterisk indicates a

    significant effect of impairment class on percent forest cover at alpha = 0.05; two asterisks

    indicate a significant effect of impairment class on percent forest cover at alpha = 0.01. .... 40

    LIST OF TABLES

    Table 1. Stream reaches sampled for macroinvertebrates, physical habitat, and water quality in

    and adjacent to the Damascus area urban growth boundary expansion, Oregon, fall 2003. . 22 Table 2. Environmental variables measured in the field for characterizing stream reaches in and

    adjacent to the Damascus area urban growth boundary expansion, Oregon, fall 2003. ....... 24 Table 3. Buffer dimensions use to calculate percent land use/cover adjacent to stream reaches

    sampled for macroinvertebrates, physical habitat, and water chemistry in and adjacent to the

     Damascus area urban growth boundary expansion, Oregon, fall 2003. ............................... 25Table 4. Metric set and scoring criteria (WQIW 1999) used to assess condition of

    macroinvertebrate communities sampled in and adjacent to the Damascus area urban growth

    boundary expansion, Clackamas County, Oregon, fall 2003. ............................................. 26 Table 5. Occurrence of Rosgen stream channel types in streams sampled for macroinvertebrates,

    physical habitat, and water chemistry in and adjacent to the Damascus area urban growth

    boundary expansion, Clackamas County, Oregon, fall 2003 .............................................. 27 Table 6. Environmental conditions of 31 stream reaches from which riffles were sampled for

    macroinvertebrates in and adjacent to the Damascus area urban growth boundary expansion,

    Clackamas County, Oregon, fall 2003. .............................................................................. 28 Table 7. Environmental variables significantly correlated (at ; = 0.01) with NMS axes resulting rdththfrom ordination of macroinvertebrate data from 3, 4, and 5-order stream reaches

    sampled in and adjacent to the Damascus area urban growth boundary expansion, Oregon,

    fall 2003. ........................................................................................................................... 29

    Table 8. Descriptive statistics of macroinvertebrate community metrics calculated from riffle

    samples collected from 31 stream reaches in and adjacent to the Damascus area urban

    growth boundary expansion, Oregon, fall 2003. ................................................................. 30 ABR Draft Report UGB Expansion Baseline Invertebrates iv

    Table 9. Multimetric scores and impairment classes of macroinvertebrate communities sampled

    from riffles in 37 stream reaches in and adjacent to the Damascus area urban growth

    boundary expansion, Clackamas County, Oregon, fall 2003. ............................................. 31

ABR Draft Report UGB Expansion Baseline Invertebrates v

    ACKNOWLEDGMENTS

     This study was funded by a grant from the US Fish and Wildlife Service / Metro Greenspaces program. Jennifer Thompson with the US Fish and Wildlife service administered the grant. Matt Killian and Adam Harris of ABR, Inc. collected much of the field data for this study. Adam and Katri Laukkanen sorted macroinvertebrate samples. J.O. Price of Metro and Rich Blaha of ABR Inc. provided GIS support.

ABR Draft Report UGB Expansion Baseline Invertebrates vi

    INTRODUCTION

    In 2002, the Urban Growth Boundary (UGB) was expanded to include more than 12,000 acres in the Damascus area, representing the single largest expansion of the UGB since its establishment. The expansion area is currently dominated by agricultural and rural residential land uses, with some small forested tracts still occurring in uplands and adjacent to streams. A number of the larger tracts of forested land are riparian corridors presently occurring in lower portions of several of the drainages within the study area.

    Urbanization of watersheds is known to have potentially profound effects of aquatic habitat and aquatic life, including fish and macroinvertebrate communities. Assessing the condition of natural resources in the UGB expansion project area prior to urbanization will provide baseline data of pre-urbanization ecological conditions against which future conditions can be compared in relation to development patterns. Monitoring physical and biological conditions in streams before and during urbanization of the area will help determine just what effects urban development will have on area streams.

    Examining macroinvertebrate communities has gained wide acceptance as a reliable and meaningful tool for monitoring the condition of surface waters. Because these biological communities integrate the effects of multiple stressorsexcess nutrients,

    toxic chemicals, increased temperature, excessive sediment loading, and othersthey

    provide a reliable measure of the overall ability of a water body to support aquatic life. A study of macroinvertebrate communities in the upper and middle Tualatin River basin in 2001 indicated that area macroinvertebrate communities respond measurably to degraded stream conditions and their condition can be related to surrounding land use conditions (Cole 2002). A number of other regional assessments of macroinvertebrate communities in northern Willamette Valley streams have been performed in efforts to characterize the current condition of aquatic resources and to establish baseline data for comparison with future monitoring efforts (e.g. Adams 2001, Cole 2003, Cole 2004).

    The primary objective of this study was to characterize current benthic macroinvertebrate and physical habitat conditions in streams occurring within the project area and to provide the first year of data in a long-term study of responses of stream ABR Draft Report UGB Expansion Baseline Invertebrates 1

    habitat and macroinvertebrate communities to urbanization. A secondary objective of the study was to investigate the effects of forested buffers within the study area on macroinvertebrate community conditions.

    STUDY AREA

     The Damascus Urban Growth boundary expansion area encompasses

    approximately 12,000 acres in northwestern Clackamas County, Oregon (Figure 1). Several tributary watersheds to the Clackamas River occur entirely, or partially, in the southern portion of the proposed expansion area, including (west to east) Rock Creek, Richardson Creek, and Noyer Creek. Rock Creek, the westernmost Clackamas River tributary, occurs almost entirely within the expansion area. All but approximately the lower ? miles of Richardson Creek occurs within the proposed expansion area. Approximately the 1/3 of the Noyer Creek drainage occurs within the expansion area. North Fork Deep Creek, immediately to the east of Noyer Creek, doesn’t occur within the current proposed expansion area, but was included for sampling in this study owing to its close proximity.

     Several tributaries to Johnson Creek occur in the northern portion of the expansion area, including Kelly Creek and several smaller unnamed tributaries. All of these tributaries drain in a generally northerly direction. Butler Creek occurs immediately north of the proposed expansion area and is entirely forested in its upper reaches. Sampling for this study occurred on Kelly Creek, Butler Creek, and one unnamed tributary in the northeast corner of the proposed expansion area.

     Land use throughout the entire expansion area consists of a mosaic of rural residential, rural, agricultural, and forested land uses. Both upland and riparian forested areas still occur in the area. Of particular note is the intact riparian corridors on lower North Fork Deep, lower Noyer, lower Richardson, parts of Rock, and upper Butler Creeks.

ABR Draft Report UGB Expansion Baseline Invertebrates 2

    METHODS

    STUDY REACH SELECTION

     Because the primary purpose of this study was to characterize baseline physical and biological conditions in streams throughout the project area, study reaches were selected to provide relatively an even spatial coverage of perennial stream reaches within the project area. Our intent was to collect data at a sufficient number of sites to allow for examination of the data for spatial variability (longitudinal variability within and variability among drainages), while spacing reaches far enough apart to effectively detect spatial variability in biological conditions as reflected by varying physical and adjacent land use conditions.

    Where access and adequate flow allowed for sampling, study reaches were established at approximately?- to 1-mile intervals along the mainstem of each drainage, as well as on perennial tributaries. In all 34 stream reaches were established as project reaches, with the following breakdown among drainages: 11 in Rock Creek, 8 in Richardson Creek, 3 in Noyer Creek, 6 in North Fork Deep Creek (including 1 in Deep Creek), 2 in Kelly Creek, 1 in Butler Creek, and 3 in an unnamed tributary to Johnson Creek (Figure 1).

     In addition to establishing sampling reaches throughout the proposed expansion area, six sampling stations were established on the Clackamas River to track changes in the longitudinal profile of benthic biological conditions in the Clackamas River from above the Deep Creek confluence to below the Rock Creek confluence.

FIELD DATA COLLECTION

    Macroinvertebrate communities, physical habitat, and water chemistry were sampled from the 40 study reaches between September 29 and October 15, 2003. First, each study reach was marked and reach length was measured. Each sample reach measured 20 times the average wetted width or 75 m, whichever length was greater. Reach gradient was then measured with a clinometer and percent riffle, pool, and glide habitat was visually estimated. These parameters were used to categorize the study reach as low gradient or moderate gradient (Table 1). Generally, reaches with gradients ABR Draft Report UGB Expansion Baseline Invertebrates 3

Report this document

For any questions or suggestions please email
cust-service@docsford.com