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Technical Report

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water quality monitoring, Arkansas, watershed monitoring


The Arkansas Water Resources Center (AWRC) monitored water quality at eight sites in the Upper Illinois River Watershed (UIRW) during base flow conditions and storm events from July 1, 2009 through June 30, 2010. Water samples were collected manually with an alpha or Kemmerer style sampler and analyzed for nitrate-nitrogen (NO₃-N), sulfate (SO₄), chloride (Cl), soluble reactive phosphorus (SRP), total phosphorus (TP), dissolved ammonia (NH₃-N), total N (TN), total suspended solids (TSS), and turbidity. Physico-chemical parameters were measured in the field including pH, conductivity, water temperature, and dissolved oxygen concentration. The selected sites were at established discharge monitoring stations maintained by the US Geological Survey or AWRC, and constituent loads were determined using regression models between constituent concentrations, discharge, and seasonal factors to estimate daily loads, which were then summed to produce monthly and annual load estimates. The constituent loads and annual flow-weighted concentrations for the 2009 calendar year are summarized in the tables below, using the data collected in this study. The regression models were applied throughout the discharge record of the entire calendar year to estimate loads. Summary of calculated


The supplemental file is the water-date report that was used for data analysis and interpretation in this report.

DR-WQ-MSC363_UIRW.pdf (330 kB)
Data Report MSC363

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