Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

SANTA MARGARITA RIVER WATERSHED MANAGEMENT AREA STREAM BIOASSESSMENT MONITORING ANNUAL REPORT FOR THE MIDDLE SANTA MARGARITA RIVER SUBWATERSHED AREA

FISCAL YEAR 2018–2019

Prepared for:

Riverside County Santa Margarita River Subwatershed Municipal Separate Storm Sewer System Co-Permittees

October 2019

Prepared by: Wood Environment and Infrastructure Solutions, Inc.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

TABLE OF CONTENTS

1.0 Introduction ...... - 1 - 2.0 Materials and Methods ...... - 3 - Stream Monitoring Sites ...... - 3 - 2.1.1 Background ...... - 3 - Sample Collection ...... - 5 - 2.2.1 Benthic Macroinvertebrate Collection ...... - 6 - 2.2.2 Benthic Algae Collection ...... - 7 - Physical Habitat Quality Assessment ...... - 7 - 2.3.1 Additional SMC Data Collection ...... - 7 - Laboratory Processing and Analysis ...... - 8 - 2.4.1 Benthic Macroinvertebrates ...... - 8 - 2.4.2 Benthic Algae...... - 8 - Data Analysis ...... - 8 - 2.5.1 Benthic Macroinvertebrates ...... - 8 - 2.5.2 Benthic Algae...... - 9 - SMC Data Submission ...... - 9 - 3.0 Results and Discussion—Bioassessment...... - 11 - Benthic Invertebrate Community Summary ...... - 11 - Benthic Macroinvertebrate Community Metrics ...... - 11 - 3.2.1 Species Diversity and Dominance ...... - 11 - 3.2.2 Ephemeroptera, Plecoptera, and Trichoptera Taxa ...... - 11 - 3.2.3 Tolerance Measures ...... - 11 - 3.2.4 Functional Feeding Groups ...... - 12 - Physical Habitat Quality Assessment ...... - 12 - Water Quality ...... - 12 - BMI Community Summary Indices ...... - 13 - 3.5.1 Southern California Index of Biotic Integrity ...... - 13 - 3.5.2 California Stream Condition Index ...... - 14 - 4.0 Benthic Algae ...... - 17 - 4.1.1 Diatom Autecology Indicators ...... - 19 - 4.1.2 Algal Biomass ...... - 20 - 5.0 Individual Monitoring Site Results ...... - 21 - Tributary to Santa Margarita River SMC Condition Site, 902M18909 ...... - 21 - Sandia Creek SMC Trend Site, SMC01097 ...... - 23 - 6.0 SMC Special Study Preliminary Results ...... - 25 - 6.1.1 Riverine Trash Assessment ...... - 25 - 6.1.2 Sediment Chemistry and Toxicity ...... - 26 - 7.0 Summary and Conclusions ...... - 27 - 8.0 References ...... - 29 -

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

LIST OF APPENDICES

APPENDIX A: Field and Laboratory Data Sheets APPENDIX B: Detailed Data Tables

LIST OF TABLES

Table 2-1. 2018–2019 Middle SMR Stream Bioassessment Monitoring Site List ...... - 4 - Table 2-2. Water Chemical Analytes for the Southern California Stormwater Monitoring Coalition’s Regional Bioassessment Monitoring Program...... - 5 - Table 2-3. Sediment Chemical Analytes for the Southern California Stormwater Monitoring Coalition’s Regional Bioassessment Monitoring Program...... - 6 - Table 3-1. Summary of 2018–2019 Physical Water Quality Parameter Measurements ...... - 12 - Table 3-2. Southern California Index of Biotic Integrity Scoring Ranges (0–100 scale) ...... - 13 - Table 3-3. Summary of 2018–2019 SMR Watershed Southern California IBI Scores ...... - 14 - Table 3-4. Condition Category Thresholds for the California Stream Condition Index ...... - 14 - Table 3-5. Summary of 2018–2019 California Stream Condition Index Scores ...... - 15 - Table 4-1. Summary of 2018–2019 Algal IBI Scores ...... - 17 - Table 4-2. Summary of 2018–2019 Algal Community Metrics ...... - 19 - Table 4-3. Summary of 2018–2019 Algal Biomass...... - 20 - Table 6-1. Summary of Sediment Toxicity Results ...... - 26 - Table 7-1. Summary of 2018–2019 Biotic Community Index Scores...... - 28 -

LIST OF FIGURES

Figure 2-1. 2018–2019 Stream Bioassessment Monitoring Sites in the Santa Margarita River Watershed Management Area ...... - 4 - Figure 5-1. SMC Condition Site: Tributary to Santa Margarita River (902M18909) sampled 5/9/19 - 21 - Figure 5-2. SMC Trend Site: Sandia Creek (SMC01097) sampled 5/9/19 ...... - 23 -

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

1.0 INTRODUCTION

On November 18, 2015, the San Diego Regional Water Quality Control Board (Regional Board) adopted National Pollutant Discharge Elimination System (NPDES) Permit Order No. R9-2013-0001, as amended by Order Nos. R9-2015-0001 and R9-2015-0100 (Permit) to further the Clean Water Act’s objective to protect, preserve, enhance, and restore the water quality and designated beneficial uses of waters of the state. The Permit regulates dischargers of urban runoff from the municipal separate storm sewer systems (MS4s) within the Santa Margarita Region (SMR) Watershed Management Area (WMA), which include the County of Riverside, the City of Murrieta, the City of Temecula, the City of Wildomar, and the Riverside County Flood Control and Water Conservation District (District) (collectively, Co-Permittees). The Permit includes a monitoring and reporting program that identifies goals and management questions for program design and implementation and provides a basic structure for specific requirements for monitoring and reporting. Furthermore, the Water Quality Improvement Plan (WQIP) for the SMR WMA, developed to address Permit requirements and set forth goals to improve the quality of local waterways, was accepted by the San Diego Water Board on November 27, 2018. Fiscal year (FY) 2018–19 was the first implementation year of the WQIP monitoring and assessment program. Wood Environment & Infrastructure Solutions, Inc. (Wood) was contracted to perform the stream assessment monitoring portion of the SMR WMA monitoring program. Monitoring methodology and results are presented in this monitoring report.

The monitoring program includes a total of four bioassessment monitoring sites. Two sites are monitored once per Permit term for compliance with the NPDES MS4 Receiving Water Monitoring Program, and two sites that contribute to the Stormwater Monitoring Coalition (SMC) Regional Stream Survey are monitored during each year of the five-year SMC study. During FY 2018–19, bioassessment was not conducted at either of the MS4 locations; only the two SMC sites were monitored.

The SMC program is coordinated by the Southern California Coastal Water Research Project (SCCWRP), which is the central repository for data analysis and reporting for SMC participating agencies in the South Coast Region. Stream bioassessment sampling and analyses followed the protocols in the Surface Water Ambient Monitoring Program (SWAMP) Standard Operating Procedures for the Collection of Field Data for Bioassessments of California Wadeable Streams: Benthic Macroinvertebrates, Algae, and Physical Habitat (Ode et al., 2016), as well as the SMC work plan Bioassessment Survey of the Stormwater Monitoring Coalition (Mazor, 2015a).

Stream bioassessments provide a quantifiable assessment of the resident benthic macroinvertebrates (BMI) and algal communities in wadeable freshwater streams. Because these organisms live in a given water body for extended periods, they provide an integrative direct assessment of the cumulative impacts of water quality over time that other measurements, such as water chemistry and toxicity, may not (Karr & Chu, 1999). Using benthic invertebrate community species composition, taxa-specific ecology, pollution tolerance, and feeding strategies, numerical biometric indices are calculated, allowing for comparison of relative ecological health among monitoring sites and over time.

This report presents the results of sampling and analyses of the physical habitat, BMI, and algal communities at the two stream sites surveyed within the SMR Watershed on May 9, 2019. Field sampling for algae and BMI was performed by Bill Isham, John Rudolph, and Kevin Stolzenbach of Wood; laboratory analysis of BMI was performed by Thomas Gerlinger (Osprey Marine Management), Bill Isham (Wood), and Kurt King (Aquatic Assessments, Inc.); and data management and interpretation of BMI and algal data were performed by Bill Isham,

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

John Rudolph (Wood), and Corey Sheredy (Wood). Laboratory analyses and compilation of algal taxonomic data were performed by Dr. Kalina Manoylov (Georgia College and State University).

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

2.0 MATERIALS AND METHODS

This section provides a general description of the methods used during the stream bioassessment collection effort and subsequent analysis.

STREAM MONITORING SITES

2.1.1 Background Two sites are monitored within the SMR WMA in Riverside County under the current SMC program. Under the SMC probabilistic study design, sites are chosen from a randomized master sample draw list of all probabilistic sites throughout the three subwatershed areas of the SMR, provided by the SMC Program Administrator. This procedure requires that the sites on the master list be sequentially screened for suitability, and the first site that passes the SMC site selection criteria (e.g., presence of adequate flow, is safely accessible, and site access is granted) is selected for monitoring. Historically, although desktop and field reconnaissance has been conducted for sites within both the Upper and Middle SMR subwatershed areas, only the Middle subwatershed area has had sites that meet the requirements optimal for conducting bioassessment 1, as outlined in the SWAMP bioassessment methods (Ode et al., 2016) and 2015–2019 SMC work plan. Potential SMC sites screened within the Upper watershed have been observed to be dry, and therefore not suitable for bioassessment according to current SWAMP bioassessment procedures.

Two types of sites were assessed: Condition Sites and Trend Sites. Condition Sites are new sites that are selected from the SMC randomized list each year. These sites are sampled only once during the current five-year cycle (2015–2019) to determine an overall condition estimate of the health of streams in the region. Trend Sites are those that have been randomly selected from the preceding five-year SMC cycle (2009–2013) list and are being sampled each year of the current five-year cycle (2015–2019) to evaluate overall trends in the ecological health of streams in the region.

In the 2018–2019 monitoring year, one trend site (SMC01097 in Sandia Creek) and one condition site (902M18909 in an unnamed tributary off Calle Pico Road) were sampled for the SMC program. Table 2-1 lists the locations monitored during the 2018–2019 monitoring year. Figure 2-1 shows the locations of the monitoring sites.

1 SMC Stream Requirements: Stream width of at least 1-meter. Sampled reach length shall be dependent upon the width of the stream (typical distance between main transects is 15 meters for streams with <10 meter average wetted width, or can be stretched to 25 meters for streams with >10-meter average wetted width; therefore, reach lengths may range from 250 meters to 150 meters). For streams with restricted longitudinal flow, the sampled reach length can be constricted down to 100 meters, with 10-meter inter-transect distance. Stream depth shall be wadeable (<1 meter deep for >50% of reach).

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

Table 2-1. 2018–2019 Middle SMR Stream Bioassessment Monitoring Site List

Water Body/ Program Site Code Date Sampled Latitude Longitude Site Name Tributary to the Santa Margarita River (SMC 902M18909 9-May-19 33.46577 -117.19798 SMC Regional Stream Condition Site ) Survey Sandia Creek (SMC Trend Site) SMC01097 9-May-19 33.48724 -117.25558

Figure 2-1. 2018–2019 Stream Bioassessment Monitoring Sites in the Santa Margarita River Watershed Management Area

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

SAMPLE COLLECTION

At each stream site, the sampling team delineated a 150-meter stream reach from which to collect BMI and algae samples and to make physical habitat observations. Each monitoring reach was divided into 11 main transects at evenly spaced 15-meter intervals. Transects were established perpendicular to the direction of stream flow (labeled A through K from downstream to upstream) and were marked with flags along the stream bank. Inter- transects were marked at the midpoint of the 11 main transects (i.e., every 7.5 meters). Water quality parameters were measured near Transect A prior to entering the creek. In situ measurements included water temperature, pH, dissolved oxygen (DO), specific conductivity, salinity, and turbidity. All parameters were measured in the field using calibrated instruments. Grab samples were then collected at the SMC sites for chemical analyses of the standard SMC suite of water quality constituents (Table 2-2). Additionally, a sediment sample was collected at the Condition Site as part of a special SMC study to assess the chemistry and toxicity of fine sediment deposits within streams. The list of sediment sample analytes is presented in Table 2 -3.

Table 2-2. Water Chemical Analytes for the Southern California Stormwater Monitoring Coalition’s Regional Bioassessment Monitoring Program

Analyte Reporting Limit Conventionals and Major Ions Total Suspended Solids 1 mg/L Alkalinity as CaCO3 5 mg/L Hardness as CaCO3 5 mg/L Chloride 1 mg/L Sulfate 1 mg/L Nutrients Ammonia as N 0.1 mg/L Nitrogen, Total 0.2 mg/L Nitrate + Nitrite as N 0.1 mg/L Phosphorus as P 0.05 mg/L Orthophosphate as P 0.05 mg/L Algal Biomass AFDM 1 g/m 2 Chlorophyll-a 10 mg/m 2 Notes: AFDM = Ash-Free Dry Mass; CaCO3 = calcium carbonate; g/m 2 = grams per square meter; mg/L = milligrams per liter; mg/m 2 = milligrams per square meter; N=nitrogen; P = phosphorus

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

Table 2-3. Sediment Chemical Analytes for the Southern California Stormwater Monitoring Coalition’s Regional Bioassessment Monitoring Program

Analyte Reporting Limit Conventionals TOC NA Grain size 1% % Solids NA Pyrethroids Bifenthrin 0.25 ng/g Cyfluthrin, total 1.25 ng/g Cypermethrin, total 1.25 ng/g Deltamethrin/ Tralomethrin 1.00 ng/g Esfenvalerate/ Fenvalerate, total 0.50 ng/g Fenpropathrin 0.25 ng/g Permethrin, cis- 1.25 ng/g Permethrin, trans- 2.5 ng/g Cyhalothrin, lambda, total 0.50 ng/g Toxicity Hyalella azteca Survival and Growth NA (23°C) Notes: NA = not applicable; ng/g = nanograms per gram; °C = degrees Celsius

BMI and algae sampling started at the downstream end of the monitoring reach and progressed upstream to avoid disturbing portions of the creek not yet sampled. BMI and algae samples were collected using the Standard Reach-Wide Benthos (RWB) approach, approximately 1-meter downstream of each main transect, prior to physical habitat parameter assessment, as described below.

2.2.1 Benthic Macroinvertebrate Collection To collect BMI, a 1-square-foot patch of streambed was sampled at each main transect, rotating locations along each transect between 25 percent (%), 50%, and 75% of the transect width from the bank. Substrates within the delineated patch were agitated so that the associated organisms were dislodged from the substrates. The natural current of the stream carried the dislodged organisms into a 0.5-millimeter (mm) mesh D-frame net positioned immediately downstream of the sampling patch. Samples from all 11 transects were composited and transferred into 1-liter plastic sample jars and preserved with 95% ethanol. The BMI sample was returned to Wood for taxonomic identification.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

2.2.2 Benthic Algae Collection Algae were also collected at each main transect. Algae were removed from substrates using one of three standard area-delimited collection devices, depending on the substrate encountered. The number of times each collection device was used was recorded to quantify the total surface area sampled. In addition to a surface-area-quantified sample, a qualitative sample of soft algae and diatoms was collected. The qualitative sample consisted of any unique taxa that were observed within the sampling reach but may have been missed in the transect-limited samples.

The algae sample was processed onsite, creating four subsamples for analysis, including soft-bodied macroalgae, diatoms, ash-free dry mass (AFDM), and chlorophyll-a. The total algae sample composite volume was quantified for calculation of algal biomass per unit area.

PHYSICAL HABITAT QUALITY ASSESSMENT

Physical habitat characteristics were assessed once biological sampling was completed. These characteristics are used to document local conditions that may affect the instream biological communities. The primary components of the physical habitat that are assessed include streambed and bank dimensions, substrate composition, stream gradient and sinuosity, riparian vegetation characteristics, flow habitat types, and discharge volume.

To assess the overall riverine wetland habitat quality within the monitoring reach, the California Rapid Assessment Method (CRAM) was also employed at the Condition Site only. CRAM was not performed at the Trend Site in 2019, as the SMC work plan specifies that trend sites are assessed only every third year (CRAM was performed at this site in 2017), or if there has been a major change (e.g., a severe flood, restoration). The CRAM protocol assesses 14 separate wetland attributes both instream and stream-side (e.g., in-stream habitat complexity, riparian vegetation, buffer zone width and quality, adjacent land uses, and hydrologic connectivity). CRAM incorporates a broader landscape scope than the SWAMP physical habitat assessment and yields a single condition score for a site. The range of possible scores is 25 to 100 points, with higher scores representing higher quality wetlands. The scoring system has yet to be calibrated to give categorical ratings such as "Poor" or "Good" that correspond to specific score ranges.

2.3.1 Additional SMC Data Collection In addition to the standard biological and physical habitat data collected, the SMC work plan calls for assessing several other data types. Analyses of these additional data will be conducted by SCCWRP in the five-year SMC assessment report. Field data sheets were completed for each of these (with the exception of water level loggers) and are included in Appendix A:

• Assessment of Hydrologic States: Flow habitats and the dominant state of discharge in the creek. • Channel Engineering Checklist: Channel characteristics/substrate, bank composition, and grade control features. • Hydromodification Physical Habitat Assessment (PHAB) Module: Bank height and angle, median particle size, vertical susceptibility to erosion, and lateral susceptibility to adjustments. • Vertebrate Observation Reporting Form: Invasive vertebrates and estimated abundance.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

• Water Level Loggers: Long-term continuous monitoring of the depth of water within the reach sampled through the dry season for Condition Sites (i.e., until late September/early October), or year-round at Trend Sites.

LABORATORY PROCESSING AND ANALYSIS

2.4.1 Benthic Macroinvertebrates Laboratory processing of the BMI samples followed the procedures in the SWAMP Standard Operating Procedures for Laboratory Processing and Identification of Benthic Macroinvertebrates in California (Woodward et al., 2012). Samples were processed so that at least 500 organisms were removed from the sample and the percentage of the sample processed was recorded so that a total abundance for the sample could be estimated. Organisms were identified to standard taxonomic Level II effort, as specified in the Southwest Association of Freshwater Invertebrate Taxonomists’ (SAFIT) List of Freshwater Invertebrate Taxa (Richards and Rogers, 2011), using standard taxonomic keys (e.g., Larson et al., 2000; Merritt and Cummins, 1996; Smith, 2001; Thorp and Covich, 2001; Usinger, 1956; Wiggins, 1998).

2.4.2 Benthic Algae Laboratory processing of the algae samples followed the procedures in the SWAMP Standard Operating Procedures for Laboratory Processing, Identification, and Enumeration of Stream Algae (Stancheva et al., 2015). The procedure includes a standard numerical count of 600 valves per sample for diatoms while macroalgae, microalgae, and epiphytes are quantified as biovolume per unit area.

Algal biomass samples were processed by an analytical laboratory using methods SM 2540(G) and SM 10200(H) for AFDM and chlorophyll-a, respectively.

DATA ANALYSIS

2.5.1 Benthic Macroinvertebrates A taxonomic list of BMIs identified from the samples was created using Microsoft Excel and included the designated tolerance value (TV) and functional feeding group (FFG) of each taxon. BMI community-based biological metric values were calculated from the data.

In addition to the individual metric values, two multi-metric community summary indices were calculated: the southern California Index of Biotic Integrity (SoCal IBI; IBI) and the California Stream Condition Index (CSCI). The IBI is a quantitative scoring system for assessing the quality of benthic macroinvertebrate assemblages (Ode et al., 2005). The multi-metric IBI distills seven key measures of organism abundance, diversity, and function into a single composite score that varies predictably in response to stressors. The IBI was developed using a multi-year comprehensive assessment of reference and nonreference conditions in southern California to establish an expected range of BMI community structure in the region.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

The recently developed CSCI is a California statewide index (Mazor et al., 2016). This index is considered an improvement over the southern California IBI because it incorporates predictors of the natural ecological conditions throughout California that could affect BMI community composition based on natural gradients. These predictors include latitude, elevation, watershed area, mean annual precipitation, and mean annual temperature. CSCI scores are based on a reference stream expectation score of 1.0 (i.e., the mean for all reference sites statewide), and biological condition classes are set statistically from that benchmark. Although no official regulatory benchmarks are currently set based on the CSCI, Mazor et al. (2016) considered the top two condition classes of "Likely Intact" and "Possibly Altered" (i.e., a CSCI score ≥ 0.79) to be statistically similar to reference condition, with scores below 0.79 to be likely altered from reference.

The CSCI score is the mean of two indices of biological condition: (1) a predictive multi-metric index of biotic integrity (pMMI), and (2) a ratio of the observed taxa at a site to the expected taxa at a site (O/E). The pMMI index incorporates six separate metrics that have a linear response to environmental stressors. The metrics selected decrease in response to impairment of water quality and/or physical habitat. The O/E index is based on the probability of capture of individual organisms in response to stream-specific conditions. Using the combination of a multi-metric index and an O/E index improves the accuracy over using the two individually, because experience has shown that both have limitations when assessing unusual BMI assemblages or sites with unique natural conditions.

2.5.2 Benthic Algae A Microsoft Excel taxonomic list of benthic algae taxa identified from the samples was created to calculate biological metric values and diagnostic metrics for specific ecological conditions. The metrics were recently developed and validated for southern California, as were three algal IBIs specific to the region (Fetscher et al., 2014). The IBIs are presented in three versions: the S2, which assesses soft algae and cyanobacteria; the D18, which assesses diatoms; and the H20, which is a combination of the S2 and the D18 IBIs. The IBI metrics are each on a scale of 0 to 10, while final IBI scores are on a scale of 0 to 100, with higher values representing higher quality algal communities. These algal analysis tools have not yet been integrated into regulatory policy, and categorical condition classes have not been officially defined, therefore care must be taken when interpreting and discussing the results.

SMC DATA SUBMISSION

Data generated from the field and laboratory efforts will be submitted to the SMC Program Data Manager at SCCWRP in standard format Microsoft Excel spreadsheets created specifically for the SMC program, or through web-based entry interfaces. Physical habitat data will be entered into a Microsoft Access format database and submitted to the SMC Data Manager; CRAM data will be entered into the on-line eCRAM data portal that is accessible by the SMC Data Manager. All applicable SMC data will then be uploaded to the California Environmental Data Exchange Network (CEDEN) state-wide database by the SCCWRP Data Manager.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

3.0 RESULTS AND DISCUSSION—BIOASSESSMENT

This section summarizes the results of the 2018–2019 Bioassessment Surveys. Tables listing complete results are provided in Appendix B.

BENTHIC INVERTEBRATE COMMUNITY SUMMARY

A total of 51 distinct taxa representing 1,192 individual organisms were identified from the monitoring sites (Appendix B-1 and B-3). The mayfly, Baetis sp., was the most abundant organism at the two sites combined, with 388 individuals; followed by the black fly, Simulium sp., with 292 individuals; and the non-biting midge, Micropsectra sp, with 66 individuals (Appendix B-2). Organism abundance, which represents the total number of organisms in the 11 square feet (ft 2) of stream substrate sampled, ranged from 9,350 organisms at the Condition Site to 5,258 at the Trend Site (Appendix B-3).

BENTHIC MACROINVERTEBRATE COMMUNITY METRICS

3.2.1 Species Diversity and Dominance Macroinvertebrate taxa richness ranged from 30 taxa at the Condition Site to 40 taxa at the Trend Site ( Appendix B-3). Dominance by a single taxon was 30.1% at the Condition Site (Simulium sp.), and 41.7% at the Trend Site (Baetis sp.). It is not uncommon for impaired streams to have greater than 80% dominance by a single taxon, therefore both streams have relatively good evenness regarding taxa abundance.

3.2.2 Ephemeroptera, Plecoptera, and Trichoptera Taxa Most insects in the orders Ephemeroptera, Plecoptera, and Trichoptera (EPT) are considered sensitive, and do not tolerate poor water quality conditions, but some from this group are moderately tolerant to impairment (e.g., the mayfly Baetis adonis ). The number of EPT taxa ranged from 5 taxa at the Condition Site to 7 taxa at the Trend Site. Sensitive EPT (those with a tolerance value (TV) ≤ 3) collected included the stonefly, Malenka sp. and the caddisfly, Lepidostoma sp. at the Condition Site; and Malenka sp. and the stonefly, Isoperla sp. at the Trend Site.

3.2.3 Tolerance Measures For most of the stream BMI, a TV has been determined for each taxon through prior research on the animals’ life history (e.g., Hilsenhoff, 1987). These TVs rank BMI taxa on a scale of 0 to 10 in terms of their sensitivity to impairment, with a TV of 0 given to taxa that are highly sensitive to habitat or water quality impairment and a TV of 10 given to those that are very tolerant. While organisms with a high TV can be found in streams with good water and habitat quality, they tend to be a smaller proportion of the community. Conversely, taxa with low TVs (i.e., sensitive organisms) will very rarely be found at sites with poor water or habitat quality.

The Hilsenhoff Biotic Index (an abundance-weighted mean community TV) was 5.43 at the Condition Site and 5.45 at the Trend Site. Highly intolerant (i.e., sensitive) organisms (TV of 0–2) were present at both sites, and accounted for 5.7% of the community at the Condition Site and 3.0% at the Trend Site. Highly tolerant organisms (TV of 8-10) accounted for 3.4% of the community at the Condition Site and 7.3% at the Trend Site.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

3.2.4 Functional Feeding Groups As with TV, FFG designations have been determined through prior research of life history for each taxon. A healthy assemblage will typically contain a more even distribution of feeding strategies, while dominance of the community by a single FFG, particularly collector taxa, suggests that the stream may not support a diversity of ecological niches and may be a general indicator of poor stream health. Collector-gatherers dominated both sites, but were in relatively low concentrations, with 42.2% at the Condition Site and 65.9% at the Trend Site. Collector- gatherers feed on fine particulate organic detritus, algae, and various micro-organisms (Smith, 2001; Usinger, 1956) and are often associated with high levels of urbanization and runoff (Lenat and Crawford, 1994).

PHYSICAL HABITAT QUALITY ASSESSMENT

Section 5 discusses the physical habitat characteristics of each monitoring site individually. The monitoring sites were both in natural stream channels with riparian zones ranging from moderately to minimally altered. Quantified summaries of the physical habitat characteristics at the monitoring sites are provided in Appendix B- 4. The SWAMP field data sheets containing physical habitat observations, as well as the CRAM field data sheets for the SMC sites, are provided in Appendix A. Densiometer readings were converted to percent vegetative cover according to the procedures outlined in Strickler (1959).

WATER QUALITY

In situ water quality measurements taken in the field at the time of sampling are presented in Table 3-1, and analytical results for the chemistry samples are provided in Appendix B-5. The water quality results were elevated for several constituents at the Condition and Trend Sites, including specific conductivity (1,693 and 1,926 microSiemens per centimeter [µS/cm], respectively), chloride (200 and 300 milligrams per liter [mg/L], respectively) and sulfate (400 and 380 mg/L, respectively). Total nitrogen concentration (mostly from Nitrate) was also somewhat elevated at the Condition Site (20 mg/L). Chloride and sulfate were identified as high priority stressors in the South Coast Region in the SMC Program’s five-year report (Mazor, 2015b).

Table 3-1. Summary of 2018–2019 Physical Water Quality Parameter Measurements

Tributary to Sandia Creek Station Santa Margarita River (SMC Trend) (SMC Condition) Site Code 902M18909 SMC01097

Water Temperature (°C) 15.4 16.1

pH 7.79 8.15

Dissolved Oxygen (mg/L) 8.96 10.20

Specific Conductivity (µS/cm) 1,693 1,926

Turbidity (NTU) 2.6 5.0

Salinity (ppt) 0.86 0.99

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

BMI COMMUNITY SUMMARY INDICES

Two indices were used to assess the overall quality of the BMI communities at the bioassessment monitoring sites: the southern California IBI and the CSCI. The results of these calculations are presented below.

3.5.1 Southern California Index of Biotic Integrity Table 3-2 shows the seven metrics used to calculate the SoCal IBI scores in accordance with Ode et al. (2005). The table also provides the scoring ranges for each metric and the qualitative ratings (i.e., Very Poor, Poor, Fair, Good, and Very Good). Each of the seven metric values is given a score from 0 to 10, and the scores are added to give the total SoCal IBI score. The cumulative total is then standardized to a scale of 0–100 by multiplying the raw score by 1.43. The final score is then classified into one of the five quality rating categories.

Table 3-2. Southern California Index of Biotic Integrity Scoring Ranges (0–100 scale)

Number Number Percent Percent Percent Percent Metric Number Coleoptera Predator CF+CG Intolerant Non-Insect Tolerant Score EPT Taxa Taxa Taxa Individuals Individuals Taxa Taxa 10 >5 >17 >12 0–59 25 –100 0–8 0–4 9 16 –17 12 60 –63 23 –24 9–12 5–8 8 5 15 11 64 –67 21 –22 13 –17 9–12 7 4 13 –14 10 68 –71 19 –20 18 –21 13 –16 6 11 –12 9 72 –75 16 –18 22 –25 17 –19 5 3 9–10 8 76 –80 13 –15 26 –29 20 –22 4 2 7–8 7 81 –84 10 –12 30 –34 23 –25 3 5–6 6 85 –88 7–9 35 –38 26 –29 2 1 4 5 89 –92 4–6 39 –42 30 –33 1 2–3 4 93 –96 1–3 43 –46 34 –37 0 0 0–1 0–3 97 –100 0 47 –100 38 –100 Notes: Total IBI Score Quality Ratings (source: Ode et al., 2005): • Very Poor: 0–19 • Poor: 20–39 • Fair: 40–59 • Good: 60–79 • Very Good: 80 –100 CF+CG = collector filterers plus collector gatherers; EPT = Ephemeroptera, Plecoptera, and Trichoptera

The SoCal IBI is quite accurate in broadly identifying stream impairment, which is defined as the cutoff between the Poor and Fair categories (score of ≤39). Small differences in SoCal IBI scores are not significant and may be due to natural biological variability within a stream reach. Ode et al. (2005) determined that the "minimum detectable difference" between scores is approximately 13 points; therefore, a site score must be at least 13 points higher or lower to be considered of significantly higher or lower quality than another. The total SoCal IBI scores and community quality ratings for each site are presented in Table 3-3 and the complete results, including individual metric values and scores, are presented in Appendix B-6.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

The SoCal IBI rated the two bioassessment monitoring sites below the impairment threshold of 39 points (Table 3-3), with scores of 27 (Poor) at the Condition Site and 31 (Poor) at the Sandia Creek Trend Site.

Table 3-3. Summary of 2018–2019 SMR Watershed Southern California IBI Scores

Overall SoCal Categorical Site Name Site Code IBI Score 1 Ranking Tributary to the Santa Margarita 902M18909 27 Poor River (SMC Condition) Sandia Creek SMC01097 31 Poor (SMC Trend) Notes: 1. Sum of individual SoCal IBI metric scores multiplied by 1.43 and rounded to the nearest whole number to convert to a 100-point scale. SMC = Stormwater Monitoring Coalition

3.5.2 California Stream Condition Index BMI condition categories for the CSCI, which are calculated as percentiles of the statewide reference pool data set (n=473 sites), are presented in Table 3-4. A summary of site CSCI scores are presented in Table 3-5, and more complete documentation of the CSCI calculation results is presented in Appendix B-7 and B-8. The results contrasted with the SoCal IBI ratings for both sites, and the CSCI rated both sites above the CSCI impairment threshold (i.e., 0.79), while the IBI did not.

Table 3-4. Condition Category Thresholds for the California Stream Condition Index

Condition Category CSCI Scoring Range Likely Intact ≥0.92 Possibly Altered 0.79 to 0.91 Likely Altered 0.63 to 0.78 Very Likely Altered 0.00 to 0.62 Notes: Source: Mazor et al., 2016 CSCI = California Stream Condition Index

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

Table 3-5. Summary of 2018–2019 California Stream Condition Index Scores

Site Name Site Code Condition Category Final CSCI Score 1 O/E Score pMMI Score Tributary to Santa Margarita River (SMC 902M18909 Possibly Altered 0.87 1.15 0.60 Condition ) Sandia Creek (SMC SMC01097 Likely Intact 0.97 1.25 0.69 Trend ) Notes: 1 - Final CSCI scores are the average of the O/E and pMMI scores. CSCI = California Stream Condition Index; O/E = ratio of observed to expected taxa; pMMI = predictive multi-metric index.

The CSCI analysis rated the Condition Site as Possibly Altered with a CSCI score of 0.87. The Trend Site was rated Likely Intact with a CSCI score of 0.97. For both sites, the O/E component score was much higher than the pMMI, which indicated that taxonomic completeness was equivalent to reference while community structure and function were below reference expectations.

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4.0 BENTHIC ALGAE

A discussion of the analytical results for the benthic algae samples is presented below. Full taxa lists of both soft algae and diatoms are provided in Appendix B-9 (soft algae) and B-10 (diatoms). Individual algal metric values that compose the algal IBI scores are presented in Appendix B-11 . Information is also given regarding each metric’s autecology (i.e., the physiological optima and tolerance of algal species). The metric values are on a 0- to 10-point scale derived statistically from the raw metric values (which may increase or decrease in response to impairment), with higher values representing healthier ecological conditions.

Algal species considered pollution-tolerant (e.g., polysaprobous and α-mesosaprobous) are often found in higher abundance in streams with poor water and habitat quality; however, these taxa can also be found in higher-quality streams. Conversely, taxa considered sensitive or pollution-intolerant (e.g., oligosaprobous and β-mesosaprobous taxa) will very rarely be found at sites with poor water or habitat quality.

Algae are good indicators of water quality conditions, notably nutrient and organic enrichment, and also indicate major ion, dissolved oxygen, and stream microhabitat conditions. The autecology (i.e., the physiological optima and tolerance of algal species for various water quality contaminants and conditions) is relatively well understood for certain groups of freshwater algae, particularly diatoms. These algal characteristics are used to help understand the condition of a river or stream, particularly in association with other stream health indicators.

Algal IBIs specific to the South Coast Region were calculated to assess the biotic integrity of the algal communities (Fetscher et al., 2014). Table 4-1 summarizes the algal IBI scores for the sites sampled. Algal IBI scores have not yet been calibrated to provide qualitative rankings or impairment thresholds, and a statewide algal IBI is currently under development by SCCWRP.

The S2 soft algal community IBI scores ranged from 28 at the Condition Site to 33 at the Trend Site. However, the IBI calculator output file indicated that neither of these sites had adequate diversity of macroalgae taxa to confidently calculate representative IBI scores (the sites had two and three quantified macroalgae taxa, respectively). The D18 diatom IBI scores were 54 at the Condition Site to 28 at the Trend Site. Overall combined H20 algal IBI scores were 50 at the Condition Site and 34 at the Trend Site. All of these individual IBI scores are relatively low on the 0-100-point scale, indicating algal communities that were somewhat degraded.

Table 4-1. Summary of 2018–2019 Algal IBI Scores

Tributary to Santa Margarita Sandia Creek Site Name River (SMC (SMC Trend) Condition) Site Code 902M18909 SMC01097 Soft Algae and 28 33 Cyanobacteria IBI: S2 Diatoms IBI: D18 54 28 Combined Overall IBI: 50 34 H20 Notes: IBI = South Coast Index of Biotic Integrity

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

Basic algal community summary metrics are presented in Table 4-2. The Trend Site had fewer unique taxa (35) than the Condition Site (50). Diatom richness was greater at the Condition Site (37 taxa, versus 24 at the Trend Site) while the soft algae taxa richness was similar with 13 and 11 taxa, respectively.

Total soft algal biovolume, a measure of the estimated mass of soft algae in the entire sampling reach, was higher at the Condition Site, and the dominant taxon was Cladophora glomerata compared with Vaucheria sp. 1 at the Trend Site. Vaucheria is considered a pollutant-intolerant taxon, while Cladophora glomerata is indicative of nutrient enriched, non-reference conditions (Fetscher, 2013). This is likely corroborated by the total nitrogen concentrations of the two sites, with values of 20 mg/L at the Condition Site compared with 6 mg/L at the Trend Site ( Appendix B-5). While Cladophora glomerate was also found at the Trend Site as the 2 nd most abundant soft algae taxa, its absolute abundance was far below that observed at the Condition Site.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

Table 4-2. Summary of 2018–2019 Algal Community Metrics

Tributary to Santa Sandia Creek Site Name Margarita River SMC Trend Site SMC Condition Site Site Code 902M18909 SMC01097 All Algae

Total Taxa Richness 50 35

Diatoms Taxa Richness 37 24 Planothidium Planothidium Dominant Taxon lanceolatum frequentissimum

Dominant Taxon Abundance 165 153

Dominant Taxon Percent 27.5 25.5

Soft Algae Taxa Richness 13 11 Cladophora Dominant Taxon by Volume Vaucheria sp 1 glomerata

Dominant Taxon Volume Percent 75.2 80.1

Total Biovolume (µm 3/cm 2) ÷ 10,000,000 5,652 3,534

Notes: µm 3/cm 2 = cubic micrometers per square centimeter

4.1.1 Diatom Autecology Indicators The Condition and Trend Sites both contained relatively low proportions of pollution-intolerant diatom taxa (i.e., oligosaprobous and β-mesosaprobous taxa), with metric scores of 2 and 3, respectively (Appendix B-11 ). Both sites also consistently had low scores for metrics that respond to nutrients. The two dominant diatom taxa at these sites were Planothidium lanceolatum at the Condition Site and Planothidium frequentissimum at the Trend Site, both of which can indicate elevated nitrogen concentrations, eutrophic conditions, and are moderately tolerant to pollutants.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

4.1.2 Algal Biomass Algal biomass measures of chlorophyll-a and AFDM exhibited a range of conditions at the two sites (Table 4-3). At the Trend Site, chlorophyll-a concentration was relatively high with a value of 28.1 micrograms per square meter (µg/m 2) while AFDM was relatively low with a value of 1.7 mg/cm2. At the Condition Site chlorophyll-a was 7.6 µg/m 2 and AFDM was 10.4 mg/cm 2. The higher AFDM value at the Condition Site may be related to the higher amount of coarse particulate organic matter observed in the streambed (e.g., decomposing leaf litter, twigs, etc.), where it was observed at 49.5% of the substrate points ( Appendix B-4), while at the Trend Site it was observed at 38.1% of the substrate points (AFDM measures all organic matter, whether it is algae or not). This could also be a result of the difference in overhead riparian tree cover between the two sites, as the measured canopy cover was much denser at the Condition Site (Appendix B-4).

Table 4-3. Summary of 2018–2019 Algal Biomass

Tributary to Sandia Creek Site Name Santa Margarita River (SMC Trend) (SMC Condition)

Site Code 902M18909 SMC01097

Chlorophyll-a (mg/m 2) 10.4 28.1

Ash-free Dry Mass (g/m 2) 7.6 1.7 Notes: g/m 2 = grams per square meter; mg/m 2 = milligrams per square meter; SMC = Stormwater Monitoring Coalition

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

5.0 INDIVIDUAL MONITORING SITE RESULTS

This section presents the key findings from each individual site sampled.

TRIBUTARY TO SANTA MARGARITA RIVER SMC CONDITION SITE, 902M18909

Figure 5-1. SMC Condition Site: Tributary to Santa Margarita River (902M18909) sampled 5/9/19

The unnamed tributary to Santa Margarita River, SMC Condition Site (Figure 5-1) is located at the end of Calle Pico Road at an elevation of approximately 1,280 feet. The source of dry weather flows at this Condition Site was observed to be rising groundwater that was very likely enhanced from upstream irrigation by commercial

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey orchard operations. The creek had a diverse and complex substrate that was ideal for BMI and algae colonization. There were frequent riffles, cobbles, boulders, and high gradient sections. Filamentous algae covered 31% of the reach and aquatic macrophytes covered 12% of the reach (Appendix B-4). Coarse particulate organic matter (a food resource for BMI) was detected at 50% of the substrate measurement points. The overhead riparian canopy was heavy throughout the reach, with total coverage of 75%, while the streamside upper and lower canopy layers exhibited moderate to heavy coverage. Ground cover vegetation, including woody shrubs and saplings was moderate with 31% reach-wide coverage, while herbaceous plants and grasses were slightly less with 19% coverage. Observed human influences near the creek included a private road within 50 meters of the right streambank and avocado orchards within 200 meters upstream of the sampling reach. Human visitation to the stream is likely infrequent and there was little trash observed, although there was some deposition of agricultural materials (e.g., irrigation pipe and sand-bags). The CRAM score for the reach was 78, indicating a riparian corridor in moderately good condition.

The BMI community was rated Poor by the SoCal IBI and had a CSCI rating of Possibly Altered. The community was dominated by the black fly, Simulium sp. and the mayfly, Baetis sp. Both of these taxa are generalists in their ecological requirements and are common in urban streams. Other taxa that indicated good water quality conditions included the stonefly, Malenka sp., the dragonfly, Cordulegaster dorsalis , the caddisfly, Wormaldia sp., and the meniscus midge, Dixa sp. Specific conductivity was elevated to a moderate degree with a concentration of 1,693 µS/cm. This is likely high enough to prevent colonization of taxa that are sensitive to high ionic strength.

The algae community exhibited IBI scores of 28 (soft algae), 54 (diatoms), and 50 (combined overall) (Table 4- 1). Individual metrics of the diatom community indicated that the site was not impacted by fine sediment or low dissolved oxygen levels. Diatom metrics that indicate eutrophication showed mixed signals, and there were few taxa that indicate low concentrations of nitrogen and phosphorus. The soft algal metric scores were mostly low, with indications of high nitrogen-tolerant taxa, and moderate scores for taxa that indicate high organic carbon and low phosphorus concentrations.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

SANDIA CREEK SMC TREND SITE, SMC01097

Figure 5-2. SMC Trend Site: Sandia Creek (SMC01097) sampled 5/9/19

The Sandia Creek SMC Trend Site (Figure 5-2) is located along De Luz Road at an elevation of approximately 885 feet. Water sources are likely primarily from rising groundwater enhanced by irrigation of avocado and citrus orchards. The monitoring site is located within private property and was observed to have undergone some alteration from the winter storm season with areas of bank scouring and sand deposition (a review of the CRAM attributes indicated that this streambed alteration would not affect the overall score, therefore CRAM was not re- assessed). Riparian vegetative habitat provides heavy overhead canopy cover (69% of the reach) but relatively sparse streamside canopy and herbaceous/grass ground cover (all ≤ 25%).

The creek substrate was dominated by sand and gravel (58% and 25%, respectively), while cobble, which provides considerable habitat space for BMI and algae, composed 10% of the substrate. Instream habitat was moderately complex, including a mix of woody debris, aquatic macrophytes, live tree roots, undercut banks, and overhanging

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey vegetation. The gradient was low (1.3%) and flow volume was higher than most years (0.71 ft 3/sec). Flow habitats across the reach were composed of shallow-water glides (68% of the reach) and riffles (32%).

The BMI community was rated Poor by the SoCal IBI, but was rated Likely Intact (i.e., statistically similar to reference) by the CSCI. The BMI community was dominated by the mayfly, Baetis sp. (39.8% of the community), followed by the black fly, Simulium sp. (19.5%). There were five highly sensitive BMI taxa collected, including the stoneflies, Isoperla sp. and Malenka sp., the dobsonfly, Neohermes sp., the meniscus midge, Dixa sp., and the moth fly, Maruina lanceolata . Other signals of a high-quality BMI community included low percentages of non-insect taxa and a moderate diversity of predators and EPT taxa.

The algae community had IBI scores of 33 (soft algae), 28 (diatoms), and 34 (combined overall) ( Table 4-1). These values indicated poor algal community conditions. Most of the diatom metrics showed signals of poor water quality conditions, with the exception of those that indicate low dissolved oxygen. Many of the soft algae metrics had very low scores although metrics for non-reference indicator taxa and proportion of chlorophytes scored high.

Both the BMI and algal biotic indices in 2019 showed a decrease from historical surveys. It is likely that the higher than typical rainfall the previous winter had a scouring effect and that the biological communities had not fully recovered by the time sampling was performed.

Relative to the previous 2017-2018 monitoring period:

• Flow volume increased from 0.01 ft 3/sec to 0.71 ft 3/sec and mean wetted width increased from 1.6 m to 5.0 m. • Cobble substrate decreased from 26% to 9.5%. • Ground cover vegetation decreased from about 40% to approximately 10%. • BMI SoCal IBI decreased from 51 (Fair) to 31 (Poor). • Algal H20 IBI decreased from 64 to 34.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

6.0 SMC SPECIAL STUDY PRELIMINARY RESULTS

This section provides the results of the SMC special studies conducted at the two SMC stream bioassessment sites. Copies of the field checklists and data sheets are provided in Appendix A. The results will be incorporated into the regional SCCWRP SMC database and will be included in reports to be released by the SMC Program Manager as data are analyzed and relevant conclusions are made.

Assessment of Hydrologic States : The dominant state of discharge in both of the creeks was classified as "eurheic" (base flow), defined as follows: "Water always below banks. Discharge is high enough to allow access to most of the streambed." The flow at the unnamed tributary Condition Site consisted of cascades (0.2% of the reach), fast shallow riffle habitat (31.0%), slow shallow glide habitat (67.8%), and slow deep pool habitat (1.0%). The Sandia Creek Trend Site had less flow variability, and the reach consisted of 32.0% riffle habitat and 68.0% glide habitat.

Channel Engineering Checklist : Both channels were recorded as natural, and grade control features were absent within 10 meters upstream or downstream of the sampling reach.

Hydromodification PHAB Module : Because the channels were noted to be natural, particle size and bank angle were quantified.

The channel and banks at the Condition Site had a median particle size of fine gravel. The banks angles ranged from 21 to 53 degrees and were assessed to be resistant to vertical and lateral adjustments (i.e., erosion).

The Sandia Creek Trend Site had a median particle size of sand. Bank angles ranged from 32 to 62 degrees. The stream was observed to have lateral adjustments occurring on the right bank and susceptible to lateral adjustments on the left bank, with poorly consolidated toe material. Vertical susceptibility was assessed to be intermediate with effective grade controls greater than 100 meters apart, with a road crossing approximately 50 meters upstream of the sampling reach.

Vertebrate Observation Reporting Form : At the Condition Site, vertebrates observed within the monitoring reach included the Pacific tree frog, with more than 50 larvae and 1 to 10 adults observed. No invasive amphibians, invasive invertebrates, or fish were observed.

At the Sandia Creek Trend Site, >50 Pacific tree frog larvae and 11-50 adults were observed, and 1-10 unidentified non-native fish were observed.

6.1.1 Riverine Trash Assessment The trash assessment rated the Condition Site as having a low level of trash (visual score = 2) as an overall first visual impression. Upon closer inspection between main transects A-C2, a total of 9 pieces of trash were tallied, characterized mostly as soft plastic pieces and some synthetic fabric from deteriorated sand bags.

2 Two types of assessment are performed as part of the SMC trash assessment. The first is to give an overall first impression of the trash density on a 0-12 scale with higher scores indicating a higher level of trash. The second is to perform a detailed tally of all trash types present within the bankfull margins between main transects A and C.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

The Sandia Creek Trend Site was also rated as having a low level of trash as a first visual impression (visual score = 2). A total of 13 pieces of trash were tallied between transects A-C. These were mostly plastic wrappers and bags, and a couple pieces of large construction materials (fencing and telephone pole).

6.1.2 Sediment Chemistry and Toxicity Sufficient deposits of fine sediment suitable for chemistry and toxicity were observed at the Condition Site. Sediment samples were collected from the finest deposits available within the monitoring reach to represent a "worst case scenario." Toxicity tests included a 10-day growth and survival test using the amphipod, Hyalella azteca , and chemistry analytes included pyrethroid pesticides, particle size, and total organic carbon. Laboratory reports are provided in Appendix A .

Results of the toxicity testing are presented in Table 6-1. The sediment showed no significant effects to growth or survival of H. azteca . Amphipods exposed to the sediment exhibited survival within 4% of the control, and exhibited greater growth than the control. The only pyrethroid that was detected was Fenpropathrin, at a concentration of 5.7 ng/dry g. Particle size analysis showed the sample was 8.5% silt/clay, 89.3% sand, and 2.2% gravel. Total organic carbon was 1.9%.

Table 6-1. Summary of Sediment Toxicity Results

Mean % Amphipod Mean Biomass Sample ID (Hyalella azteca ) % Effect % Effect (mg/org) Survival

Laboratory Control 96 NA 0.230 NA

902M18909 92 4.2 0.254 -10.4

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

7.0 SUMMARY AND CONCLUSIONS

Two stream sites in the Santa Margarita River WMA were monitored for BMI and algae in May 2019. The two sites were part of the SMC Regional Stream Survey program. Sampling and analysis followed the SMC work plan and standardized SWAMP field and laboratory procedures. This stream bioassessment study fulfills the District’s Permit requirements and the data derived from this effort will be provided to the SMC program and/or to the SWAMP statewide, publicly available CEDEN database.

Both of the sites sampled were in natural stream channels with at least moderate riparian vegetation and ample flowing water at the time of monitoring. Physical habitat quality was relatively good, and both sites had a variety of stable stream substrates, native riparian buffer habitat and canopy, and flow regimes. Both sites also had agricultural operations (primarily citrus and avocado orchards) and low-density rural development in the watersheds above the monitoring sites.

Analyses of the BMI communities used two separate indices: the SoCal IBI and the statewide CSCI. These indices were not in agreement for either site (Table 7-1). Both were categorized below the impairment threshold for the SoCal IBI (i.e., <39) but were rated as equivalent to reference by the CSCI (i.e., > 0.79). When the multi- metric component of the CSCI is compared to the (multi-metric) IBI, there was agreement that the BMI communities were lacking in overall structure and function, while the predictive component of the CSCI (O/E) indicated that both sites had taxonomic completeness statistically similar to reference condition.

Analyses of the algal communities showed that both of the sites had relatively low algal IBI scores, with slightly better conditions recorded at the Condition Site ( Table 7-1). Algae respond somewhat differently to stream ecological conditions than do BMI and the most observable signal in moderately altered waterbodies is a greater sensitivity to nutrient levels. Both sites had consistently low scores for individual IBI metrics that respond to nutrients. However, there were diatom metrics at the Condition Site that indicated a lack of eutrophication and sedimentation, while at the Trend Site there were soft algae metrics that indicated reference taxa were present.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

Table 7-1. Summary of 2018–2019 Biotic Community Index Scores

Tributary to Site Name Santa Margarita River Sandia Creek (SMC Trend) (SMC Condition) Site Code 902M18909 SMC01097 SoCal BMI IBI Score 27 31 SoCal BMI IBI Ranking Poor Poor

CSCI Score 0.87 0.97

CSCI Condition Category Possibly Altered Likely Intact Soft Algae IBI: S2 28 33 Diatom IBI: D18 54 28 Combined Algae IBI: H20 50 34 Notes: BMI = benthic macroinvertebrate; CSCI = California Stream Condition Index; IBI = Index of Biotic Integrity; SMC = Stormwater Monitoring Coalition

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8.0 REFERENCES

Fetscher, A.E. 2013. Development of Algal Indices of Biotic Integrity for Southern California Wadeable Streams and Recommendations for their Applications, v3. Technical Report 730. Southern California Coastal Water Research Project. Costa Mesa, CA.

Fetscher, A.E., R. Stancheva, J.P. Kociolek, R.G. Sheath, E.D. Stein, R.D. Mazor, P.R. Ode, and L.B. Busse. 2014. Development and comparison of stream indices of biotic integrity using diatoms vs. non-diatom algae vs. a combination. Journal of Applied Phycology 26:433-450.Hilsenhoff, W. 1987. "An Improved Biotic Index of Organic Stream Pollution." In Great Lakes Entomologist . 20:31–39.

Hilsenhoff, W. 1987. "An Improved Biotic Index of Organic Stream Pollution." In Great Lakes Entomologist. 20:31–39.

Larson, D., Y. Alarie, and R. Roughly. 2000. Predaceous Diving Beetles (Coleoptera: Dytiscidae) of the Nearctic Region . NRC Research Press, Ottowa.

Lenat, D. and J. Crawford. 1994. "Effects of Land Use on Water Quality and Aquatic Biota of Three North Carolina Piedmont Streams." In Hydrobiologia . 294:185–199.

Karr, J.R. and E.W. Chu. 1999. Restoring Life in Running Waters: Better Biological Monitoring . Island Press, Covelo, California.

Mazor, R. 2015a. Bioassessment Survey of the Stormwater Monitoring Coalition. Workplan for the Years 2015 through 2019, Version 1.0. SCCWRP Technical Report 849.

Mazor, R. 2015b. Bioassessment of Perennial Streams in Southern California: A Report on the First Five Years of the Stormwater Monitoring Coalition’s Regional Stream Survey. Southern California Coastal Water Research Program Technical Report 844.

Mazor, R.D., A. Rehn, P.R. Ode, M. Engeln, K. Schiff, E. Stein, D. Gillett, D. Herbst, C.P. Hawkins. 2016. Bioassessment in complex environments: Designing an index for consistent meaning in different settings. Freshwater Science 35(1):249–271.Merritt, R.W. and K.W. Cummins. 1996. An Introduction to the Aquatic Insects of North America . Third Edition. Kendall Hunt Publishing Company. Dubuque, Iowa.

Merritt, R.W. and K.W. Cummins. 1996. An Introduction to the Aquatic Insects of North America. Third Edition. Kendall Hunt Publishing Company, Dubuque, Iowa.

Ode P.R., A.C. Rehn, and J.T. May. 2005. "A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams." In Environmental Management . 35(1):1–13.

Ode, P.R., A.E., Fetscher, and L.B. Busse. 2016. Standard Operating Procedures for the Collection of Field Data for Bioassessments of California Wadeable Streams: Benthic

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Macroinvertebrates, Algae, and Physical Habitat. California State Water Resources Control Board Surface Water Ambient Monitoring Program (SWAMP) Bioassessment SOP 004

Richards, A. and C. Rogers. 2011. List of Macroinvertebrate Taxa from California and Adjacent States and Ecoregions; and Standard Taxonomic Effort . Accessed at: http://www.safit.org/Docs/STE_1_March_2011_7MB.pdf. Edited by A. Richards and D. Rogers. March 2011.

Riverside County Flood Control and Water Conservation District. 2014. Consolidated Monitoring Program (CMP). Santa Margarita Region Monitoring Plan. Volume III (Rev 3). July 2014.

Smith, D.G. 2001. Pennak’s Freshwater Invertebrates of the United States: Porifera to Crustacea, 4 th Edition . Jon Wiley and Sons, Inc., New York, NY.

Stancheva, R., L. Busse, J.P. Kociolek, and R.G. Sheath. 2015. Standard Operating Procedures for Laboratory Processing and Identification of Stream Algae. California State Water Resources Control Board Surface Water Ambient Monitoring Program (SWAMP) Bioassessment SOP 0003.

Strickler, G.S. 1959. Use of the densiometer to estimate density of forest canopy on permanent sample plots . United States Department of Agriculture Forest Service, Pacific Northwest Forest and Range Experiment Station. Portland Oregon, December 1959.

Thorp, H.T. and A.P. Covich. 2001. Ecology and Classification of North American Freshwater Invertebrates . Second edition. Academic Press, Inc., San Diego, California.

Usinger, R.L. 1956. Aquatic Insects of California . University of California Press, Berkeley, California.

Wiggins, G. 1998. Larvae of the North American Caddisfly Genera (Trichoptera) . Second Edition. University of Toronto Press, Toronto.

Woodward, M.E., J. Slusark, and P.R. Ode. 2012. SWAMP Bioassessment Procedure 2012. Standard Operating Procedures for Laboratory Processing and Identification of Benthic Macroinvertebrates in California . October 2012. Available at: http://www.waterboards.ca.gov/water_issues/programs/swamp/docs/bmi_lab_sop_final. pdf.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix A

APPENDIX A: FIELD AND LABORATORY DATA SHEETS

Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix A

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WORK ORDER NUMBER: 19-05-0823

AIR SOIL WATER MARINE CHEMISTRY

Analytical Report For Client: Wood Environment & Infrastructure Solutions, Inc. Client Project Name: Riverside County Flood Control District SMC Bioassessment 2019 Attention: John Rudolph 9177 Sky Park Court San Diego, CA 92124-4302

Approved for release on 05/30/2019 by: Carla Hollowell Project Manager

Eurofins Calscience (Calscience) certifies that the test results provided in this report meet all NELAC Institute requirements for parameters for which accreditation is required or available. Any exceptions to NELAC Institute requirements are noted in the case narrative. The original report of subcontracted analyses, if any, is attached to this report. The results in this report are limited to the sample(s) tested and any reproduction thereof must be made in its entirety. The client or recipient of this report is specifically prohibited from making material changes to said report and, to the extent that such changes are made, Calscience is not responsible, legally or otherwise. The client or recipient agrees to indemnify Calscience for any defense to any litigation which may arise. Page 2 of 18

Contents Client Project Name: Riverside County Flood Control District SMC Bioassessment 2019 Work Order Number: 19-05-0823

1 Work Order Narrative...... 3

2 Sample Summary...... 4

3 Client Sample Data...... 5 3.1 Pyrethroids by EPA 8270D (M)/TQ/EI (Solid)...... 5 3.2 ASTM D4464 (M) Particle Size Laser (Solid)...... 6 3.3 EPA 9060A Total Organic Carbon (Solid)...... 7 3.4 SM 2540 B (M) Total Solids (Solid)...... 8

4 Particle Size Summary - 19-05-0823...... 9

5 Quality Control Sample Data...... 10 5.1 MS/MSD...... 10 5.2 Sample Duplicate...... 12 5.3 LCS/LCSD...... 13

6 Glossary of Terms and Qualifiers...... 15

7 Chain-of-Custody/Sample Receipt Form...... 16

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Work Order Narrative

Work Order: 19-05-0823 Page 1 of 1

Condition Upon Receipt: Samples were received under Chain-of-Custody (COC) on 05/10/19. They were assigned to Work Order 19-05-0823. Unless otherwise noted on the Sample Receiving forms all samples were received in good condition and within the recommended EPA temperature criteria for the methods noted on the COC. The COC and Sample Receiving Documents are integral elements of the analytical report and are presented at the back of the report. Holding Times: All samples were analyzed within prescribed holding times (HT) and/or in accordance with the Calscience Sample Acceptance Policy unless otherwise noted in the analytical report and/or comprehensive case narrative, if required. Any parameter identified in 40CFR Part 136.3 Table II that is designated as "analyze immediately" with a holding time of <= 15 minutes (40CFR-136.3 Table II, footnote 4), is considered a "field" test and the reported results will be qualified as being received outside of the stated holding time unless received at the laboratory within 15 minutes of the collection time. Quality Control: All quality control parameters (QC) were within established control limits except where noted in the QC summary forms or described further within this report. Subcontractor Information: Return to Contents Unless otherwise noted below (or on the subcontract form), no samples were subcontracted. Additional Comments: Air - Sorbent-extracted air methods (EPA TO-4A, EPA TO-10, EPA TO-13A, EPA TO-17): Analytical results are converted from mass/sample basis to mass/volume basis using client-supplied air volumes. Solid - Unless otherwise indicated, solid sample data is reported on a wet weight basis, not corrected for % moisture. All QC results are always reported on a wet weight basis.

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Sample Summary

Client: Wood Environment & Infrastructure Solutions, Work Order: 19-05-0823 Inc. Project Name: Riverside County Flood Control District SMC Bioassessment 2019 9177 Sky Park Court PO Number: San Diego, CA 92124-4302 Date/Time 05/10/19 19:20 Received: Number of 1 Containers: Attn: John Rudolph

Sample Identification Lab Number Collection Date and Time Number of Matrix Containers 902M18909 19-05-0823-1 05/09/19 10:45 1 Sediment Return to Contents

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Analytical Report

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: EPA 3541 Method: EPA 8270D (M)/TQ/EI Units: ug/kg Project: Riverside County Flood Control District SMC Page 1 of 1 Bioassessment 2019

Client Sample Number Lab Sample Date/Time Matrix Instrument Date Date/Time QC Batch ID Number Collected Prepared Analyzed 902M18909 19-05-0823-1-AA 05/09/19 Sediment GCTQ 1 05/14/19 05/17/19 190514L12 10:45 19:12 Comment(s): - Results are reported on a dry weight basis. Parameter Result RL DF Qualifiers Bifenthrin ND 1.2 1.00 Cyfluthrin ND 1.2 1.00 Cypermethrin ND 1.2 1.00 Deltamethrin/Tralomethrin ND 1.2 1.00 Fenpropathrin 5.7 1.2 1.00 Fenvalerate/Esfenvalerate ND 1.2 1.00 Permethrin (cis/trans) ND 2.4 1.00 lambda-Cyhalothrin ND 1.2 1.00

Surrogate Rec. (%) Control Limits Qualifiers Dibutylchlorendate 99 23-161

Return to Contents Method Blank 099-14-403-208 N/A Solid GCTQ 1 05/14/19 05/17/19 190514L12 18:19 Parameter Result RL DF Qualifiers Bifenthrin ND 0.50 1.00 Cyfluthrin ND 0.50 1.00 Cypermethrin ND 0.50 1.00 Deltamethrin/Tralomethrin ND 0.50 1.00 Fenpropathrin ND 0.50 1.00 Fenvalerate/Esfenvalerate ND 0.50 1.00 Permethrin (cis/trans) ND 1.0 1.00 lambda-Cyhalothrin ND 0.50 1.00

Surrogate Rec. (%) Control Limits Qualifiers Dibutylchlorendate 100 23-161

RL: Reporting Limit. DF: Dilution Factor. MDL: Method Detection Limit.

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Analytical Report

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: N/A Method: ASTM D4464 (M) Units: % Project: Riverside County Flood Control District SMC Page 1 of 1 Bioassessment 2019

Client Sample Number Lab Sample Date/Time Matrix Instrument Date Date/Time QC Batch ID Number Collected Prepared Analyzed 902M18909 19-05-0823-1-A 05/09/19 Sediment LPSA 1 N/A 05/14/19 10:45 14:27 Parameter Result Qualifiers Clay (less than 0.00391mm) 1.04 Silt (0.00391 to 0.0625mm) 7.49 Total Silt and Clay (0 to 0.0625mm) 8.53 Very Fine Sand (0.0625 to 0.125mm) 7.02 Fine Sand (0.125 to 0.25mm) 16.57 Medium Sand (0.25 to 0.5mm) 24.41 Coarse Sand (0.5 to 1mm) 24.03 Very Coarse Sand (1 to 2mm) 17.25 Gravel (greater than 2mm) 2.20 Return to Contents

RL: Reporting Limit. DF: Dilution Factor. MDL: Method Detection Limit.

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Analytical Report

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: N/A Method: EPA 9060A Units: % Project: Riverside County Flood Control District SMC Page 1 of 1 Bioassessment 2019

Client Sample Number Lab Sample Date/Time Matrix Instrument Date Date/Time QC Batch ID Number Collected Prepared Analyzed 902M18909 19-05-0823-1-AA 05/09/19 Sediment TOC 10 05/15/19 05/16/19 J0515TOCL1 10:45 18:21 Comment(s): - Results are reported on a dry weight basis. Parameter Result RL DF Qualifiers Carbon, Total Organic 1.9 0.12 1.00

Method Blank 099-06-013-1958 N/A Solid TOC 10 05/15/19 05/16/19 J0515TOCL1 18:21 Parameter Result RL DF Qualifiers Carbon, Total Organic ND 0.050 1.00 Return to Contents

RL: Reporting Limit. DF: Dilution Factor. MDL: Method Detection Limit.

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Analytical Report

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: N/A Method: SM 2540 B (M) Units: % Project: Riverside County Flood Control District SMC Page 1 of 1 Bioassessment 2019

Client Sample Number Lab Sample Date/Time Matrix Instrument Date Date/Time QC Batch ID Number Collected Prepared Analyzed 902M18909 19-05-0823-1-AA 05/09/19 Sediment N/A 05/13/19 05/13/19 J0513TSB1 10:45 17:00 Parameter Result RL DF Qualifiers Solids, Total 41.3 0.100 1.00

Method Blank 099-05-019-4480 N/A Solid N/A 05/13/19 05/13/19 J0513TSB1 17:00 Parameter Result RL DF Qualifiers Solids, Total ND 0.100 1.00 Return to Contents

RL: Reporting Limit. DF: Dilution Factor. MDL: Method Detection Limit.

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PARTICLE SIZE SUMMARY (ASTM D422 / D4464M)

AMEC WOOD Date Sampled: 05/09/19 Date Received: 05/10/19 Work Order No: 19-05-0823 Date Analyzed: 05/14/19 Method: ASTM D4464M

Project: Riverside County Flood Control District SMC bioassessment 2019 Page 1 of 1

Mean Depth Grain Size Sample IDft Description mm 902M18909 Coarse Sand 0.626

Particle Size Distribution, wt by percent Very Very Total Total Coarse Coarse Medium Fine Fine Silt & Gravel Sand Sand Sand Sand Sand Silt Clay Clay 2.20 17.25 24.03 24.41 16.57 7.02 7.49 1.04 8.53 Return to Contents

V 3.0

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Quality Control - Spike/Spike Duplicate

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: EPA 3541 Method: EPA 8270D (M)/TQ/EI Project: Riverside County Flood Control District SMC Page 1 of 2 Bioassessment 2019

Quality Control Sample ID Type Matrix Instrument Date Prepared Date Analyzed MS/MSD Batch Number 902M18909 Sample Sediment GCTQ 1 05/14/19 05/17/19 19:12 190514S12 902M18909 Matrix Spike Sediment GCTQ 1 05/14/19 05/17/19 21:49 190514S12 902M18909 Matrix Spike Duplicate Sediment GCTQ 1 05/14/19 05/17/19 22:41 190514S12 Parameter Sample Spike MS MS MSD MSD %Rec. CL RPD RPD CL Qualifiers Conc. Added Conc. %Rec. Conc. %Rec. Bifenthrin ND 5.000 5.873 117 5.452 109 26-128 7 0-30 Cyfluthrin ND 5.000 6.471 129 6.812 136 10-131 5 0-30 3 Cypermethrin ND 5.000 5.969 119 6.049 121 10-136 1 0-30 Deltamethrin/Tralomethrin ND 5.000 7.643 153 7.829 157 13-190 2 0-30 Fenpropathrin 2.336 5.000 9.078 135 8.638 126 10-148 5 0-30 Fenvalerate/Esfenvalerate ND 5.000 6.435 129 6.540 131 10-149 2 0-30 Permethrin (cis/trans) ND 5.000 6.724 134 6.357 127 45-123 6 0-30 3 lambda-Cyhalothrin ND 5.000 7.975 160 7.794 156 10-123 2 0-30 3 Return to Contents

RPD: Relative Percent Difference. CL: Control Limits

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Quality Control - Spike/Spike Duplicate

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: N/A Method: EPA 9060A Project: Riverside County Flood Control District SMC Page 2 of 2 Bioassessment 2019

Quality Control Sample ID Type Matrix Instrument Date Prepared Date Analyzed MS/MSD Batch Number 19-05-0532-1 Sample Sediment TOC 10 05/15/19 05/16/19 18:21 J0515TOCS1 19-05-0532-1 Matrix Spike Sediment TOC 10 05/15/19 05/16/19 18:21 J0515TOCS1 19-05-0532-1 Matrix Spike Duplicate Sediment TOC 10 05/15/19 05/16/19 18:21 J0515TOCS1 Parameter Sample Spike MS MS MSD MSD %Rec. CL RPD RPD CL Qualifiers Conc. Added Conc. %Rec. Conc. %Rec. Carbon, Total Organic 0.9500 3.000 4.100 105 3.963 100 75-125 3 0-25 Return to Contents

RPD: Relative Percent Difference. CL: Control Limits

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Quality Control - Sample Duplicate

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: N/A Method: SM 2540 B (M) Project: Riverside County Flood Control District SMC Page 1 of 1 Bioassessment 2019

Quality Control Sample ID Type Matrix Instrument Date Prepared Date Analyzed Duplicate Batch Number 19-05-0768-1 Sample Solid N/A 05/13/19 00:00 05/13/19 17:00 J0513TSD1 19-05-0768-1 Sample Duplicate Solid N/A 05/13/19 00:00 05/13/19 17:00 J0513TSD1 Parameter Sample Conc. DUP Conc. RPD RPD CL Qualifiers Solids, Total 28.90 28.70 1 0-10 Return to Contents

RPD: Relative Percent Difference. CL: Control Limits

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Quality Control - LCS/LCSD

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: EPA 3541 Method: EPA 8270D (M)/TQ/EI Project: Riverside County Flood Control District SMC Page 1 of 2 Bioassessment 2019

Quality Control Sample ID Type Matrix Instrument Date Prepared Date Analyzed LCS/LCSD Batch Number 099-14-403-208 LCS Solid GCTQ 1 05/14/19 05/17/19 16:34 190514L12 099-14-403-208 LCSD Solid GCTQ 1 05/14/19 05/17/19 17:27 190514L12 Parameter Spike Added LCS Conc. LCS LCSD Conc. LCSD %Rec. CL RPD RPD CL Qualifiers %Rec. %Rec. Bifenthrin 5.000 5.135 103 5.630 113 26-128 9 0-25 Cyfluthrin 5.000 4.299 86 4.870 97 10-131 12 0-25 Cypermethrin 5.000 3.916 78 4.444 89 10-136 13 0-25 Deltamethrin/Tralomethrin 5.000 4.167 83 4.761 95 13-190 13 0-25 Fenpropathrin 5.000 4.930 99 5.544 111 10-148 12 0-25 Fenvalerate/Esfenvalerate 5.000 4.022 80 4.534 91 10-149 12 0-25 Permethrin (cis/trans) 5.000 4.875 97 5.479 110 45-123 12 0-25 lambda-Cyhalothrin 5.000 5.203 104 5.638 113 10-123 8 0-25 Return to Contents

RPD: Relative Percent Difference. CL: Control Limits

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Quality Control - LCS/LCSD

Wood Environment & Infrastructure Solutions, Inc. Date Received: 05/10/19 9177 Sky Park Court Work Order: 19-05-0823 San Diego, CA 92124-4302 Preparation: N/A Method: EPA 9060A Project: Riverside County Flood Control District SMC Page 2 of 2 Bioassessment 2019

Quality Control Sample ID Type Matrix Instrument Date Prepared Date Analyzed LCS/LCSD Batch Number 099-06-013-1958 LCS Solid TOC 10 05/15/19 05/16/19 18:21 J0515TOCL1 099-06-013-1958 LCSD Solid TOC 10 05/15/19 05/16/19 18:21 J0515TOCL1 Parameter Spike Added LCS Conc. LCS LCSD Conc. LCSD %Rec. CL RPD RPD CL Qualifiers %Rec. %Rec. Carbon, Total Organic 0.6000 0.6084 101 0.5827 97 80-120 4 0-20 Return to Contents

RPD: Relative Percent Difference. CL: Control Limits

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Glossary of Terms and Qualifiers

Work Order: 19-05-0823 Page 1 of 1

Qualifiers Definition * See applicable analysis comment. < Less than the indicated value. > Greater than the indicated value. 1 Surrogate compound recovery was out of control due to a required sample dilution. Therefore, the sample data was reported without further clarification. 2 Surrogate compound recovery was out of control due to matrix interference. The associated method blank surrogate spike compound was in control and, therefore, the sample data was reported without further clarification. 3 Recovery of the Matrix Spike (MS) or Matrix Spike Duplicate (MSD) compound was out of control due to suspected matrix interference. The associated LCS recovery was in control. 4 The MS/MSD RPD was out of control due to suspected matrix interference. 5 The PDS/PDSD or PES/PESD associated with this batch of samples was out of control due to suspected matrix interference. 6 Surrogate recovery below the acceptance limit. 7 Surrogate recovery above the acceptance limit. B Analyte was present in the associated method blank. BU Sample analyzed after holding time expired. BV Sample received after holding time expired. CI See case narrative. E Concentration exceeds the calibration range. ET Sample was extracted past end of recommended max. holding time. HD The chromatographic pattern was inconsistent with the profile of the reference fuel standard. HDH The sample chromatographic pattern for TPH matches the chromatographic pattern of the specified standard but heavier hydrocarbons were also present (or detected). HDL The sample chromatographic pattern for TPH matches the chromatographic pattern of the specified standard but lighter hydrocarbons were also present (or detected). J Analyte was detected at a concentration below the reporting limit and above the laboratory method detection limit. Reported value is Return to Contents estimated. JA Analyte positively identified but quantitation is an estimate. ME LCS Recovery Percentage is within Marginal Exceedance (ME) Control Limit range (+/- 4 SD from the mean). ND Parameter not detected at the indicated reporting limit. Q Spike recovery and RPD control limits do not apply resulting from the parameter concentration in the sample exceeding the spike concentration by a factor of four or greater. SG The sample extract was subjected to Silica Gel treatment prior to analysis. X % Recovery and/or RPD out-of-range. Z Analyte presence was not confirmed by second column or GC/MS analysis. Solid - Unless otherwise indicated, solid sample data is reported on a wet weight basis, not corrected for % moisture. All QC results are reported on a wet weight basis. Any parameter identified in 40CFR Part 136.3 Table II that is designated as "analyze immediately" with a holding time of <= 15 minutes (40CFR-136.3 Table II, footnote 4), is considered a "field" test and the reported results will be qualified as being received outside of the stated holding time unless received at the laboratory within 15 minutes of the collection time. A calculated total result (Example: Total Pesticides) is the summation of each component concentration and/or, if "J" flags are reported, estimated concentration. Component concentrations showing not detected (ND) are summed into the calculated total result as zero concentrations.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

APPENDIX B : DETAILED DATA TABLES

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Spring 2019 Survey

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

TABLE OF CONTENTS

B-1.0 TAXONOMIC LISTING OF BENTHIC MACROINVERTEBRATES ...... - 1 - B-2.0 RANKED ABUNDANCE OF BENTHIC MACROINVERTEBRATES ...... - 4 - B-3.0 SELECTED BENTHIC MACROINVERTEBRATES BIOLOGICAL METRICS .. - 6 - B-4.0 SUMMARY OF PHYSICAL HABITAT CHARACTERISTICS...... - 7 - B-5.0 CHEMISTRY RESULTS ...... - 8 - B-6.0 INDEX OF BIOTIC INTEGRITY SCORES ...... - 9 - B-7.0 PREDICTIVE MULTI-METRIC SCORES ...... - 10 - B-8.0 CALIFORNIA STREAM CONDITION INDEX RESULTS ...... - 11 - B-9.0 TAXONOMIC LISTING OF SOFT ALGAE COLLECTED ...... - 12 - B-10.0 TAXONOMIC LISTING OF DIATOMS COLLECTED ...... - 13 - B-11.0 INDIVIDUAL METRIC SCORES ...... - 15 -

...... LIST OF TABLES

Table B-1: Taxonomic Listing of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 1 - Table B-2. Ranked Abundance of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 4 - Table B-3. Selected BMI Biological Metrics for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 6 - Table B-4. Summary of the Physical Habitat Characteristics of the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 7 - Table B-5. Chemistry Results for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 8 - Table B-6. Index of Biotic Integrity Scores for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 9 - Table B-7. Predictive Multi-Metric Scores (pMMI)1 of BMI Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 10 - Table B-9. Taxonomic Listing of Soft Algae Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 12 - Table B-10. Taxonomic Listing of Diatoms Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 13 - Table B-11. Individual Metric Scores for the 2018-2019 Bioassessment Monitoring Sites within Riverside County ...... - 15 -

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-1.0 TAXONOMIC LISTING OF BENTHIC MACROINVERTEBRATES

Table B-1: Taxonomic Listing of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Santa Sandia Creek Margarita River Taxon TV FFG (SMC Trend Site) (SMC Condition Site) 902M18909 SMC01097 PHYLUM ARTHROPODA Insecta Ephemeroptera (mayflies) Baetidae Baetis sp 5 cg 137 251 Baetis adonis 5 cg 12 Callibaetis sp 9 cg 3 Fallceon sp 4 cg 5 51 Leptophlebidae Paraleptophlebia sp 4 cg 2 Odonata (dragonflies, damselflies) Coenagrionidae 9 p Argia sp 7 p 1 Cordulegastridae Cordulegaster dorsalis 3 p 1 Plecoptera (stoneflies) Nemouridae Malenka sp 2 sh 13 9 Perlodidae 2 p Isoperla sp 2 p 2 Megaloptera (alderflies, dobsonflies) Corydalidae Neohermes sp 0 p 2 Trichoptera (caddisflies) Hydropsychidae 4 cf Hydropsyche sp 4 cf 44 9 Lepidostomatidae Lepidostoma sp 1 sh 8 Coleoptera (beetles) Dytiscidae Agabus sp 8 p 2 Diptera (true flies) Ceratopogonidae 6 p 1 Bezzia/Palpomyia sp 6 p 1 Chironomidae 6 cg Apedilum sp 6 cg 6 Brillia sp 5 sh 15 11 Corynoneura sp 7 cg 8 8 Cricotopus sp 7 cg 25 Cricotopus/Bicinctus group 7 cg 1 Endochironomus sp 10 cg 1 Eukiefferiella sp 8 om 12 10 Labrundinea 6 p 2

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

Table B-1: Taxonomic Listing of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Santa Sandia Creek Margarita River Taxon TV FFG (SMC Trend Site) (SMC Condition Site) 902M18909 SMC01097 Limnophyes sp 8 cg 1 1 Metriocnemus sp cg 5 Micropsectra sp 7 cg 52 14 Nilotanypus sp 6 p 1 Paracladopelma sp 7 1 Parametriocnemus sp 5 cg 15 1 Pentaneura sp 6 p 2 Polypedilum sp 6 om 20 4 Pseudosmittia sp cg 2 Rheocricotopus sp 6 om 15 20 Rheotanytarsus sp 6 om 3 3 Tanytarsus sp 6 cf 4 2 Thienemanniella sp 6 cg 3 Thienemannimyia group 6 p 1 Culicidae 1 Dixidae Dixa sp 2 cg 11 5 Empididae 6 p Neoplasta sp 6 p 6 Ephydridae 6 1 Muscidae 6 p 1 Psychodidae cg Maruina lanceolata 2 sc 1 Pericoma/Telmatoscopus sp 4 cg 1 Simuliidae Simulium sp 6 cf 169 123 Stratiomyidae Caloparyphus/Euparyphus sp 8 cg 6 Tipulidae Tipula sp 4 om 3 Malacostraca Ostracoda (seed shrimp) 8 cg 1 14 PHYLUM CHELICERATA Arachnida Acari (mites) Hygrobatidae Atractides sp 8 p 2 8 Sperchontidae Sperchon sp 8 p 1 PHYLUM PLATYHELMINTHES Turbelleria (flatworms) 4 p 1 PHYLUM ANNELIDA Oligochaeta (earthworms) 5 cg 2 9 PHYLUM MOLLUSCA Gastropoda (snails)

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

Table B-1: Taxonomic Listing of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Santa Sandia Creek Margarita River Taxon TV FFG (SMC Trend Site) (SMC Condition Site) 902M18909 SMC01097 Pulmonata Physidae Physa sp 8 sc 3 Notes: TV=Tolerance Value: range is 0-10; 0 is intolerant to impairment. FFG=Functional Feeding Group; cg=collector gatherer, cf=collector filterer, sc=scraper, sh=shredder, p=predator, om=omnivore.

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-2.0 RANKED ABUNDANCE OF BENTHIC MACROINVERTEBRATES

Table B-2. Ranked Abundance of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Santa Margarita River (SMC Trend Site) Taxon TV FFG (SMC Condition Site) Total 902M18909 SMC01097 Count Percent Composition Count Percent Composition Baetis sp 5 cg 137 24.4% 251 39.8% 388 Simulium sp 6 cf 169 30.1% 123 19.5% 292 Micropsectra sp 7 cg 52 9.3% 14 2.2% 66 Fallceon sp 4 cg 5 0.9% 51 8.1% 56 Hydropsyche sp 4 cf 44 7.8% 9 1.4% 53 Rheocricotopus sp 6 om 15 2.7% 20 3.2% 35 Brillia sp 5 sh 15 2.7% 11 1.7% 26 Cricotopus sp 7 cg 25 4.0% 25 Polypedilum sp 6 om 20 3.6% 4 0.6% 24 Malenka sp 2 sh 13 2.3% 9 1.4% 22 Eukiefferiella sp 8 om 12 2.1% 10 1.6% 22 Corynoneura sp 7 cg 8 1.4% 8 1.3% 16 Parametriocnemus sp 5 cg 15 2.7% 1 0.2% 16 Dixa sp 2 cg 11 2.0% 5 0.8% 16 Ostracoda 8 cg 1 0.2% 14 2.2% 15 Baetis adonis 5 cg 12 1.9% 12 Oligochaeta 5 cg 2 0.4% 9 1.4% 11 Atractides sp 8 p 2 0.4% 8 1.3% 10 Lepidostoma sp 1 sh 8 1.4% 8 Apedilum sp 6 cg 6 1.0% 6 Rheotanytarsus sp 6 om 3 0.5% 3 0.5% 6 Tanytarsus sp 6 cf 4 0.7% 2 0.3% 6 Neoplasta sp 6 p 6 1.1% 6 Caloparyphus/Euparyphus sp 8 cg 6 1.0% 6 Metriocnemus sp cg 5 0.9% 5 Callibaetis sp 9 cg 3 0.5% 3 Thienemanniella sp 6 cg 3 0.5% 3 Tipula sp 4 om 3 0.5% 3 Physa sp 8 sc 3 0.5% 3 Paraleptophlebia sp 4 cg 2 0.3% 2 Isoperla sp 2 p 2 0.3% 2 Neohermes sp 0 p 2 0.3% 2 Agabus sp 8 p 2 0.3% 2 Labrundinea 6 p 2 0.4% 2 Limnophyes sp 8 cg 1 0.2% 1 0.2% 2 Pentaneura sp 6 p 2 0.3% 2 Pseudosmittia sp cg 2 0.3% 2 Argia sp 7 p 1 0.2% 1 Cordulegaster dorsalis 3 p 1 0.2% 1 Ceratopogonidae 6 p 1 0.2% 1 Bezzia/Palpomyia sp 6 p 1 0.2% 1

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

Table B-2. Ranked Abundance of Benthic Macroinvertebrates Collected from the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Santa Margarita River (SMC Trend Site) Taxon TV FFG (SMC Condition Site) Total 902M18909 SMC01097 Count Percent Composition Count Percent Composition Cricotopus/Bicinctus group 7 cg 1 0.2% 1 Endochironomus sp 10 cg 1 0.2% 1 Nilotanypus sp 6 p 1 0.2% 1 Paracladopelma sp 7 1 0.2% 1 Thienemannimyia group 6 p 1 0.2% 1 Culicidae 1 0.2% 1 Ephydridae 6 1 0.2% 1 Muscidae 6 p 1 0.2% 1 Maruina lanceolata 2 sc 1 0.2% 1 Pericoma/Telmatoscopus sp 4 cg 1 0.2% 1 Sperchon sp 8 p 1 0.2% 1 Turbelleria 4 p 1 0.2% 1 Total 561 100.0% 631 100.0% 1192

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-3.0 SELECTED BENTHIC MACROINVERTEBRATES BIOLOGICAL METRICS

Table B-3. Selected BMI Biological Metrics for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Santa Margarita River SMC Sandia Creek SMC Station Condition Site Trend Site Site Code 902M18909 SMC01097 Number of Organisms Identified 561 631 Estimated Total Abundance 1 9,350 5,258 Taxa Richness 2 30 40 EPT Taxa Richness 2 5 7 Dominant Taxon Simulium sp. Baetis sp. Dominant Taxon (%) 30.1 41.7 Three Dominant Taxa (%) 63.8 67.3 Dominant Functional Feeding Collector-Gatherers Collector-Gatherers Group Intolerant Individuals (%) 5.7 3 Intolerant Taxa Richness 3 5 Tolerant Individuals (%) 3.4 7.3 Shannon -Weaver Index 2.29 2.22 Hilsenhoff Biotic Index 5.43 5.45 Functional Feeding Group Composition Collector -Filterers 38.7% 21.2% Collector -Gatherers 42.2% 65.9% Predators 2.5% 3.3% Scrapers 0.5% 0.2% Shredders 6.4% 3.2% Others 4 9.6% 6.2% Notes: 1. Estimate is based on number of organisms in the subsample and the percentage of sample sorted. 2. Taxa richness is based on SAFIT Level II taxonomic effort. 3. EPT = ephemeroptera, plecoptera, and trichoptera taxa 4. Others includes omnivores, and taxa without a feeding group designation

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-4.0 SUMMARY OF PHYSICAL HABITAT CHARACTERISTICS

Table B-4. Summary of the Physical Habitat Characteristics of the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Station Santa Margarita River (SMC Trend Site) (SMC Condition Site) Site Code 902M18909 SMC01097 Total CRAM Score 78 77 1 Flow Volume (ft 3/sec) 0.07 0.71 Mean Wetted Width (m) 2 1.4 5.0 Mean Bankfull Width (m) 3 3.4 8.4 Average Depth (cm) 4 6.6 5.7 Macroalgae Presence 4 31.4 53.3 Course Particulate Organic Matter 49.5 38.1 Presence 4 Macrophyte Presence 4 12.4 3.8 Densiometer Canopy Cover (%) 3 74.7 69.0 Upper Canopy Riparian Cover (%) 3 40.0 25.0 Lower Canopy Riparian Cover (%) 3 50.5 8.5 Riparian Ground Cover— 31.0 5.0 Shrubs/Saplings (%) 3 Riparian Ground Cover— 19.0 9.5 Herbs/Grasses (%) 3 Riparian Ground Cover—Barren 8.0 40.0 (%) 3 Sinuosity Ratio 1.15 1.05 Gradient (% slope) 5.3 2.3 Substrate Composition (%) 3 Fine 7.6 5.7 Sand 39.0 58.1 Gravel 21.0 24.8 Cobble 21.9 9.5 Boulder 8.6 1.0 Roots or Wood 1.9 1.0 Shannon-Weaver Substrate 1.51 1.14 Diversity Index Flow Habitat Types (%) 4 Cascade (vertical drop) 0.2 0.0 Riffle (fast, shallow) 31.0 32.0 Glide (slow, shallow) 67.8 68.0 Pool (slow, deep) 1.0 0.0 Notes: 1. Assessment not required in 2019, results from 2017 shown 2. Mean of all 21 transects 3. Percentage of 105 point counts 4. Mean of 11 main transects % = percentage; cm = centimeters; ft3/sec = cubic feet per second; m = meters

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-5.0 CHEMISTRY RESULTS

Table B-5. Chemistry Results for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Site Name Santa Margarita River (SMC Trend Site) (SMC Condition Site) Site Code 902M18909 SMC01097 MDL Result Analyte (mg/L) (mg/L) Chloride 0.30 / 0.61* 200 300 Sulfate 1.2 / 0.47* 400 380 Total Suspended Solids 2 4 2 Alkalinity as CaCO3 5.0 180 210 Hardness as CaCO3 6.0 630 740 Ammonia as N 0.044 ND ND Nitrogen, Total NA 20 6.0 Nitrate as N 0.060 / 0.12 20 5.5 Nitrite as N 0.0042 0.0095 J 0.016 OrthoPhosphate as P 0.016 0.047 J ND Phosphorus as P 0.02 0.09 0.06 Notes: MDL= method detection limit; mg/L=milligrams per liter; ND=not detected J=Estimated concentration detected Method Detection Limit *Method detection limits varied with the final concentration results

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-6.0 INDEX OF BIOTIC INTEGRITY SCORES

Table B-6. Index of Biotic Integrity Scores for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Number Number % % Non- % Tolerant Number % CF+CG Coleoptera Predator Intolerant Insect Taxa Taxa EPT Taxa Raw Standard Taxa Taxa Individuals IBI IBI IBI SMC Site Site Code Score Score Ratin Name (0-70 (0-100 g Scale) Scale) IBI IBI score IBI score IBI score IBI score IBI score IBI score IBI score Metric Metric value Metric value Metric value Metric value Metric Metric value Metric value Metric value

Tributary to SMR 902M18909 19 27 Poor 93% 1 28% 5 17% 6 0 0 5 2 6.0% 2 5 3 (Condition Site ) Sandia Creek SMC01097 22 31 Poor 95% 1 18% 7 27% 3 1 2 7 4 3.0% 1 7 4 (Trend Site ) Notes: IBI = Index of Biotic Integrity CF = Collector; Filterers ; CG = Collector Gatherers ; EPT = Ephemeroptera, Plecoptera, Trichoptera

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-7.0 PREDICTIVE MULTI-METRIC SCORES

Table B-7. Predictive Multi-Metric Scores (pMMI)1 of BMI Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County

Site Name Site Code Taxonomic Richness Score Percent Taxa EPT Observed Percent Taxa EPT Score Shredder Taxa Observed Shredder Taxa Score Percent Intolerant Taxa Observed Percent Intolerant Taxa Score pMMI Final ScorepMMI Percent Clinger Taxa Observed Percent Clinger Taxa Score Percent Coleoptera Taxa Observed Percent Coleoptera Taxa Score Taxonomic Richness Observed

Tributary to SMR 902M18909 0.60 8% 0.33 0% 0.00 29.05 0.78 17% 0.44 2.00 0.46 6% 0.26 (Condition Site)

Sandia Creek SMC01097 0.69 15% 0.45 3% 0.11 36.90 0.99 19% 0.48 1.00 0.31 3% 0.27 (Trend Site)

Notes: 1. Scores are an average of 20 iterations of the metric calculation, iteration variability is due to the random elimination of taxa to a standard count of 500

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-8.0 CALIFORNIA STREAM CONDITION INDEX RESULTS

Table B-8. California Stream Condition Index Results for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Multi- O/E CSCI Number Percent Percent Multi- Metric Organism Expected Observed O/E Percentile CSCI Percentile Site Code Site Code of Ambiguous Ambiguous Metric Percentile Count Taxa Taxa 2 Score of Score 3 of Iterations 1 Individuals Taxa Score of Reference Reference Reference Tributary to Santa Margarita River 902M18909 558 20 0 0 6.85 7.85 1.15 0.78 0.60 0.01 0.87 0.21 SMC Condition Site Sandia Creek SMC01097 631 20 0.16 2.38 6.94 8.70 1.25 0.91 0.69 0.04 0.97 0.43 SMC Trend Site

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-9.0 TAXONOMIC LISTING OF SOFT ALGAE COLLECTED

Table B-9. Taxonomic Listing of Soft Algae Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County

Tributary to Santa Margarita River Sandia Creek SMC Condition SMC Trend Site Unit Taxon Type Taxon Site Type

902M18909 SMC01097

Epiphyte Heteroleibleinia sp 1 count 10 10 Macroalgae Cladophora glomerata um 3/cm 2 42,478,354,978 6,116,883,117 Rhizoclonium um 3/cm 2 13,876,262,626 888,080,808 Macroalgae hieroglyphicum Macroalgae Vaucheria sp 1 um 3/cm 2 28,318,903,319 Microalgae Closterium ehrenbergii um 3/cm 2 35,676,761 12,644,720 Microalgae Heteroleibleinia sp 1 um 3/cm 2 224,443 79,548 Microalgae Leptolyngbya sp 1 um 3/cm 2 38,531 13,656 Microalgae Leptolyngbya tenuis um 3/cm 2 455,210 Microalgae Microspora sp 1 um 3/cm 2 1,414,855 Microalgae Oedogonium sp 1 um 3/cm 2 30,436,844 Microalgae Oedogonium sp 4 um 3/cm 2 2,840,510 Microalgae Phormidium sp 1 um 3/cm 2 3,478,484 85,352 Microalgae Pseudanabaena um 3/cm 2 22,476 Microalgae Tribonema affine um 3/cm 2 14,842,104 Microalgae Tribonema angustissimum um 3/cm 2 1,926,545 Microalgae Tribonema minus um 3/cm 2 70,742,736 Microalgae Tribonema viride um 3/cm 2 5,361,575 Qualitative Cladophora glomerata none present present Qualitative Oedogonium sp 4 none present Rhizoclonium none present present Qualitative hieroglyphicum Qualitative Vaucheria cf prona none present Qualitative Vaucheria sessilis none present Qualitative Vaucheria sp 1 none present

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-10.0 TAXONOMIC LISTING OF DIATOMS COLLECTED

Table B-10. Taxonomic Listing of Diatoms Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Santa Margarita River Taxon (SMC Trend Site) (SMC Condition Site) 902M18909 SMC01097 Achnanthidium exiguum 2 Achnanthidium minutissimum 13 10 Amphora pediculus 25 26 Cocconeis pediculus 16 Cocconeis placentula 96 3 Cyclotella meneghiniana 14 Entomoneis alata 2 Halamphora veneta 46 6 Hantzschia amphioxys 2 Lemnicola hungarica 4 Luticola mutica 6 Melosira varians 24 31 Meridion circulare 6 4 Meridion circulare var constrictum 4 Navicula cryptotenella 4 Navicula gregaria 16 28 Navicula microcari 4 6 Navicula normaloides 11 Navicula recens 2 Navicula reichardtiana 2 Navicula tripunctata 5 Navicula veneta 20 2 Navicula viridulacalcis 14 Nitzschia amphibia 4 Nitzschia communis 4 Nitzschia desertorum 4 Nitzschia dissipata 56 Nitzschia filiformis var conferta 4 Nitzschia frustulum 10 12 Nitzschia inconspicua 53 112 Nitzschia linearis 4 32 Nitzschia palea 2 Nitzschia palea var debilis 2 Nitzschia palea var tenuirostris 2 Planothidium frequentissimum 32 153 Planothidium lanceolatum 165 56 Planothidium pericavum 8 Reimeria uniseriata 2 Rhoicosphenia abbreviata 2 4 Sellaphora atomoides 3 Sellaphora nigri 2 Sellaphora saugerresii 4

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

Table B-10. Taxonomic Listing of Diatoms Collected for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Santa Margarita River Taxon (SMC Trend Site) (SMC Condition Site) 902M18909 SMC01097 Surirella angusta 4 Surirella ovalis 4 Synedra ulna 4 Tryblionella apiculata 2

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Riverside County Municipal Separate Storm Sewer Co-Permittees Stream Bioassessment Monitoring Annual Report Santa Margarita River Watershed Management Area Appendix B

B-11.0 INDIVIDUAL METRIC SCORES

Table B-11. Individual Metric Scores for the 2018-2019 Bioassessment Monitoring Sites within Riverside County Tributary to Sandia Creek Santa Margarita Site Name SMC Trend River SMC Site Condition Site Site Code 902M18909 SMC01097 Aquatic Life Response to Scaled Metric Scores (0-10 point Diatom Metrics Indicator Stress scale) Proportion of Achnanthes minutissima Sensitivity Decrease 1 1 Proportion of Sediment Tolerant Taxa Sensitivity Increase 7 2 Proportion of Halobiontic Taxa Sensitivity Increase 5 2 Proportion of Oligo- & Beta- Mesosaprobic Sensitivity Increase 2 3 Taxa Proportion of Taxa Requiring >50% DO Eutrophication Decrease 8 7 Staturation Proportion of Taxa Requiring Nearly 100% DO Eutrophication Decrease 1 1 Staturation Proportion of Poly - & Eutrophic Taxa Eutrophication Increase 1 3 Proportion of N Heterotrophic Taxa Eutrophication Increase 6 2 Proportion of Low P Indicator Taxa Nutrients Decrease 1 1 Proportion of Low N Indicator Taxa Nutrients Decrease 1 1 Proportion of Highly Motile Taxa Sensitivity Increase 6 2 Soft Algae Metrics Proportion of High Cu Indicator Taxa Sensitivity Increase 3 3 Proportion of High DOC Indicator Taxa Sensitivity Increase 6 6 Proportion of Low TP Indicator Taxa Nutrients Decrease 4 4 Proportion of ZHR Taxa (Zygnemataceae + Nutrients Decrease 0 0 heterocystous cyanobactera + Rhodophyta) Proportion of Non -Reference Indicator Taxa Sensitivity Increase 3 6 Proportion of Total Biovolume Composed of Sensitivity Increase 1 1 High DOC Indicator Taxa Proportion of Total Biovolume Composed of Sensitivity Increase 1 8 Non -Reference Indicator Taxa Proportion of Total Biovolume Composed of Nutrients Decrease 0 0 ZHR Taxa Proportion of Total Biovolume Composed of Eutrophication Increase 1 8 Chlorophyta Proportion of Green Macroalgae Composed of CRUS Taxa ( Cladophora glomerata , Eutrophication Increase 1 1 Rhizoclonium hieroglyphicum , Ulva flexuosa , and Stigeoclonium )

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