AN ASSESSMENT OF WATER QUALITY IN LOWER COEYMANS CREEK USING AQUATIC MACROINVERTEBRATE POPULATIONS January 24, 2020 For: Hudson River Sloop Clearwater, Inc. 724 Wolcott Ave Beacon, NY By: Jeremy Dietrich IA Environmental 600 Wolverine Way Scotts Valley, CA 95066 TABLE OF CONTENTS SECTION PAGE INTRODUCTION: 1 METHODS: 1 RESULTS: 4 DISCUSSION: 6 CONCLUSIONS: 8 REFERENCES: 9 REPORT TABLES: 10 -13 REPORT FIGURES 14- 22 APPENDIX: Photographs of collection locations 23-25 Introduction Coeymans creek is a third order stream draining the western slope of the Hudson River in Albany County, New York State. The stream travels southeast approximately 19.5 miles from its headwaters near Clarksville to its confluence with the Hudson River proper near the towns of Ravena and Coeymans. The stream is classified as a C(TS) stream by the New York State Department of Environmental Conservation (DEC). A class C stream is designated for waters supporting fisheries and suitable for non-contact activities, and TS, short for “trout spawning,” indicates protections are in place for the propagation of trout. A landscape cover of forest, industrial, and residential predominate the lower reach of Coeymans. The characteristics of Coeymans creek and its watershed have been well documented in other studies, particularly The Onesquethaw-Coeymans Watershed Study (OCWS) prepared by the Onesquethaw- Coeymans Watershed Council and Capital District Regional Planning Commission in 2008. The DEC’s Stream Biomonitoring unit sampled aquatic invertebrates in the lower reach of Coeymans in 1987, 1998, 2002, and 2013 at State Route 144; and in 1987, 1988, and 1998 at Old Ravena Rd. The DEC’s determination of water quality designation based on macroinvertebrate studies concluded a designation of slightly impacted at Old Ravena Rd and a combination of slightly and moderately impacted at SR-144. A document report by DEC’s Stream Biomonitoring Unit titled 30 Year Trends in Water Quality of Rivers and Streams in New York State Based on Macroinvertebrate Data, 1972-2002 (Bode et al., 2004) described Coeymans Creek as follows: “Coeymans Creek: Water quality in Coeymans Creek from Bethlehem Heights to Coeymans is assessed as slightly impacted, based on macroinvertebrate sampling in 1998. Probable stressors are nonpoint source nutrient enrichment, municipal/industrial inputs, and siltation.” The goal of this study was to assess aquatic macroinvertebrate populations within the lower reach of Coeymans creek between Old Ravena Rd and State Route 144. This segment of Coeymans flows through a wildlife management area and cement plant in its upper to middle reaches and an industrial park in its lower reach. A focus was to determine if industrial and commercial land use activities surrounding the lower reach of Coeymans Creek are impacting the creek by harming invertebrate populations in that vicinity. Methods Aquatic macroinvertebrates were collected from three locations within the lower reach of Coeymans Creek: (1) At the first riffle/run downstream of the bridge at Old Ravena Rd, (2) within the Coeymans Wildlife Management Area (WMA) upstream of the Industrial Park zone, and (3) at the riffle upstream of the bridge at State Route 144, and immediately downstream of Page 1 of 25 the Industrial Park zone. A map illustrating the collection sites can be found in Figure 1, and detailed coordinate locations and sample collection timing can be found in Table 1. Table 1: Coeymans Creek 2019 aquatic macroinvertebrate survey location and collection information. Location Date Time Easting Northing Sample Water (UTM, 18N) (UTM, 18N) Type Temp. (°F) Ravena Rd 07 June 2019 9:30 597942 4707435 Kick 59 Coeymans WMA 07 June 2019 14:45 598335 4706169 Kick 56 Route 144 07 June 2019 12:30 599114 4703598 Kick 58 Field Sampling At each location, a traveling kick sample was performed in riffle/run habitats to capture aquatic macroinvertebrates. Three replicate samples were taken at transects perpendicular to stream flow. The kick sample method captures benthic organisms by disturbing bottom sediments and catching the dislodged organisms in a D-framed net with a mesh size of 0.5mm. Kick samples are timed at a 5-minute duration so that capture effort is standardized. Following the instream kick, sample contents were rinsed over a 0.5mm brass sieve to eliminate any fine silt while large debris was rinsed of any organisms and removed from the sample. The samples were then placed in 1L containers, and preserved with 95% ethanol. Following the kick sample, site characteristics such as substrate composition, habitat attributes, water clarity, aquatic vegetation presence, algal/biofilm cover, tree canopy cover, and observations of animals or human impacts were qualitatively evaluated. Additionally, a hand-drawn schematic of the site was illustrated to define the exact sampling transects as they relate to local landmarks such as riparian trees or stream channel profile. Laboratory Analyses Raw sample contents were placed into and equitably distributed within a large sorting pan (40cm L x 30cm W x 6cm H) with 20 equally spaced numbered grids scribed on the bottom (see photo at right). A series of random numbers, between 1 - 20, were generated for use in subsampling. Following procedures within New York State Department of Environmental Conservation’s Standard Operating Procedure for Biological Monitoring of Surface Waters in New York State (Duffy, 2018), a robust subsample of 250 invertebrates was picked from each sample. Following the random number grid assignments, Page 2 of 25 all organisms within a single grid were picked and enumerated before moving on to the next grid. This process was repeated until at least 250 organisms were captured or the entire sample was picked. Once subsamples were obtained, aquatic invertebrates were sorted into taxonomic orders, then identified and enumerated to the lowest practical taxonomic level, often to genus. Identifications were made using a 45x dissecting microscope (Fisher Scientific Stereomaster). Organisms were then archived in ordinal-level vials and preserved in 70% Ethanol. Biotic Criteria Parameter Calculation and Impairment Determination For each site, parameter values for the following metrics were calculated: Taxa Richness (SPP), Hilsenhoff Biotic Index (HBI), Ephemeroptera- Plecoptera-Trichoptera (EPT) Richness, and Percent Model Affinity (PMA). The figure at right depicts the metric thresholds for assignment of impact designations. Taxa Richness is the total number of species or taxa found in the sample. Higher taxa richness values are mostly associated with clean-water conditions. The Hilsenhoff Biotic Index is calculated by multiplying the number of individuals of each species by its assigned tolerance value (from Table 17.11 in Smith 2014), summing these products, and dividing by the total number of individuals. On a 0-10 scale, tolerance values range from intolerant (0) to tolerant (10). EPT value denotes the total number of species of mayflies (Ephemeroptera), stoneflies (Plecoptera), and caddisflies (Trichoptera) in the subsample. These taxa are considered clean-water organisms, and their presence is correlated with good water quality. Percent Model Affinity is a measure of similarity to a model non-impacted community based on percent abundance in 7 major taxonomic groups: 40% mayflies, 5% stoneflies, 10% beetles, 10% caddisflies, 20% midges, 5% aquatic worms, and 10% other taxa. Overall assessment of water quality at a site is achieved by combining the ranking of the above index values to calculate the Biological Assessment Profile (BAP). The BAP converts the collective indices to a common 0-10 scale, where 0 indicates very poor water quality (severely impacted) and 10 being very good water quality (non-impacted). The BAP numeric scale (0-10) assigns a qualitative stream water quality designation among four categories: (1) Non-Impacted [10-7.5]: very good water quality, (2) Semi-Impacted [7.5-5]: good water quality, Page 3 of 25 (3) Moderately-Impacted [5-2.5]: poor water quality, and (4) Severely-Impacted [2.5-0]: very poor water quality. The specific methodologies for computing these biometrics as well as complete descriptions of water quality designations can be found in Duffy (2018), pp. 52-69. Water Quality Measurements Water quality monitoring occurred at each of our aquatic macroinvertebrate sampling locations on October 7, 2019. Physiochemical parameters were measured using a YSI Professional Plus handheld Mulitparameter instrument. Surface water measurements were taken for dissolved oxygen, pH, water temperature, and conductivity. Statistical Analyses For each site, replicate mean values and standard errors for each parameter were calculated. A Generalized linear model was used to compare parameter means among sites. Analysis of Variance (ANOVA) was used to compare metrics across sites, with a significance alpha value of 0.05. All analyses were performed in R, version 3.5.1 (02 July 2018). Results Ravena Rd Benthic aquatic habitat at Old Ravena Rd was favorable with overall substrate comprised of 48.3% gravel, 15% cobble, and 23.3% sand. The substrate composition at each replicate sampling location was similar (Figure 2, left panel). Aquatic macroinvertebrate sampling efforts at yielded 669 individuals across a taxonomic span of 14 Orders and 44 genera (Table 3). The macroinvertebrate community composition was dominated by midges (Diptera: Chironomidae) and aquatic worms (Oligochaeta), comprising 37.4% and 36.2%, respectively (Figure 3). Aquatic