Jason Siemion Donald B Bonville 20260330 comma separated values (csv) file, portable document format (pdf) file https://doi.org/10.5066/P136TR3D This data release contains turbidity and suspended-sediment concentration data used to develop regression models of suspended-sediment concentration at sites in the Esopus Creek watershed in New York. Also included are model summaries describing data-collection methods, application of cross-section coefficients, model development, summary statistics, and related information. In cooperation with the New York City Department of Environmental Protection, regression models were developed to estimate time series of suspended-sediment concentration (SSC) at sites in the Esopus Creek Watershed in New York. These SSC time series were used to estimate suspended-sediment load in streams and rivers upstream and downstream of the Ashokan Reservoir, the largest reservoir by surface area in the New York City drinking-water supply system. 20151001 20240914 ground condition Complete As needed -74.5192 -73.9676 42.1975 41.8446 USGS suspended sediment SSC turbidity turbidity-SSC model USGS Metadata Identifier USGS:68471d7bd4be024a7ae10501 Geographic Names Information Systems (GNIS) Esopus Creek New York None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. Jason Siemion U.S. Geological Survey Physical Scientist mailing and physical

425 Jordan Rd

Troy NY 12180 518-285-5600 Turbidity and suspended-sediment concentration included in model development were processed, reviewed, and approved following U.S.Geological Survey guidelines as outlined in Edwards and Glysson (1999), Rassmussen and others (2009), and Wagner and others (2006). Models and data used for model development were reviewed by U.S. Geological Survey staff and fall within an expected range when compared to historical data available from the monitoring sites. Data are considered complete for the study time period. Observator Analite NEP5000 turbidity and discharge data measured at a 15-minute time step as well as SSC data from discrete samples were downloaded from Water Data for the Nation for all locations included in this work with the exception of the Esopus Creek at Mt Marion, gaging station 01364500, where turbidity data were monitored with a Forest Technology Systems DTS12 turbidity probe. Samples were analyzed for SSC at the USGS Kentucky Sediment Laboratory using the methods documented by Guy (1969). Additional information on field methods can be found in Siemion and others (2021). 2025 Cross-section coefficients were developed for each monitoring location by dividing the cross-section SSC by the corresponding point-sample SSC. Two cross-section samples, A and B sets, were collected during each sampling event with a C set collected during 1 individual event. The SSC for the paired A and B cross sections were averaged if streamflow and turbidity conditions were stable during the sample collection; otherwise, the values were used individually. The turbidity and streamflow associated with each cross-section sample were averaged over the period of sample collection. Cross-section coefficients were plotted as a function of streamflow for all monitoring sites with the exception of Lower Hollow Tree Brook at State Highway 214 at Lanesville, gaging station 01362345. Cross-section coefficients were plotted as a function of turbidity at this site because 15-minute streamflow was not available. A simple linear regression (SLR) equation was developed for each relation. The SLR was then applied to the point-sample SSC to yield an adjusted SSC representative of the true cross-section SSC. 2025 Regression analysis was done using the R statistical environment (R Core Team, 2021) by examining turbidity as the explanatory variable for estimating suspended-sediment concentration. A simple linear regression model that predicts log10(SSC) was evaluated. The distribution of residuals was examined for normality and plots of residuals (the difference between the measured and predicted values) as compared to predicted SSC were examined for homoscedasticity (meaning that their departures from zero did not change substantially over the range of predicted values). Log10(turbidity) was selected as the best predictor of log10(SSC) based on residual plots, relatively high adjusted coefficient of determination (adjusted R2), and relatively low model standard percentage error (MSPE). Samples with a CooksD greater than three times the mean CooksD for all samples, Dffits absolute values greater than 0.2, and/or residuals with absolute values greater than 0.4 were deemed outliers and removed from the dataset. Samples collected within a short period of time such as those comprising a cross-section sampling set were removed from the dataset to minimize serial correlation. The log-transformed model may be retransformed to the original units so that SSC can be calculated directly. The retransformation introduces a bias in the calculated constituent. This bias may be corrected using Duan’s Bias Correction Factor (BCF). 2025 Vector G-polygon 1 0.0197395721 0.0264428802 Decimal seconds WGS_1984 WGS 84 6378137.0 298.257223563 Siemion_and Bonville_2026_Model_data.csv Comma Separated Value (CSV) file containing data. Producer Defined gaging station U.S. Geological Survey stream gage identifier Producer Defined 01362200 0136230002 dateTime Date and time of sample collection or turbidity measurement. Producer Defined In yyyy-mm-dd hh:mm format in eastern standard time. ssc Lab determined suspended-sediment concentration Producer Defined 1 8070 milligrams per Liter, mg/L turbidity Turbidity, measured with an Observator Analite NEP5000 at all gaging stations except 01364500 where a Forest Technology Systems DTS-12 turbidity meter was used. Producer Defined 0.2 1,600 formazin nephelometric units, FNU log10turb Base 10 logarithm of measured turbidity. Producer Defined -0.7 3.20 unitless discharge Volume of water passing the site per unit time, computed from stage-discharge relationship. Producer Defined NA No Data Producer defined 0.32 21,300 cubic feet per second, cfs log10Q Base 10 logarithm of computed discharge. Producer Defined NA No Data Producer defined -0.49 4.33 unitless adjssc Lab determined uspended-sediment concentration multiplied by the derived cross-section coefficient. Producer Defined 1 6,395 milligrams per Liter, mg/L log10adjssc Base 10 logarithm of suspended-sediment concentration. Producer Defined -0.03 3.81 unitless computed_ssc Suspended-sediment concentration computed with turbidity-SSC model. Producer Defined 0 3665 milligrams per Liter, mg/L removed Factor indicating if a sample was used in the model (1) or not (0). Producer Defined 1 Sample used in model. Producer defined 0 Sample not used in model. Producer defined Model Summary for XXXXXXXX.pdf Model Summary in PDF format with site and model information, model data, sediment sample collection method description, model statistics, diagnostic plots, model summary tables, and figures. XXXXXXXX refers to gaging station number. Project Defined The Model Summary "Model Summary for XXXXXXXX.pdf" documents the model development process with details, statistics, plots, and figures. U.S. Geological Survey GS ScienceBase U.S. Geological Survey mailing address

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Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Digital Data https://doi.org/10.5066/P136TR3D None 20260330 Jason Siemion U.S. Geological Survey Physical Scientist mailing and physical

425 Jordan Rd

Troy NY 12180 518-285-5600 jsiemion@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999