Model documentation for relations between continuous real-time and discrete water-quality constituents in Indian Creek, Johnson County, Kansas, June 2004 through May 2013

Effects of wastewater effluent discharge and treatment facility upgrades on environmental and biological conditions of Indian Creek, Johnson County, Kansas, June 2004 through June 2013

“…1) (Lee and others, 2005;Rasmussen and others, 2008Rasmussen and others, , 2009bRasmussen and others, , 2012Rasmussen and Gatotho, 2014). Samples were collected by several methods, including equal-width-increment (EWI) methods, grab samples, and autosampler-collected samples (Stone and Graham, 2014). Streamflow and water-chemistry data were downloaded from the USGS National Water Information System Web site at http://waterdata.usgs.gov/nwis.…”

“…Stream-water samples were collected from all six sites over a range of streamflow conditions during June 2011 through June 2013 (Stone and Graham, 2014). In addition, water samples were collected concurrent with biological samples during August 20-21, 2012 and April 2, 2013.…”

“…Single vertical or grab samples were collected from the centroid of flow during extreme low flow (U.S. Geological Survey, 2006). Additional details on discrete water-quality sample collection are provided in Stone and Graham (2014). All water samples were analyzed for suspended sediment, dissolved solids, major ions, nutrients (nitrogen and phosphorus species), organic carbon, biochemical and chemical oxygen demand (BOD and COD, respectively), and indicator bacteria.…”

“…Regression models were developed for all six Indian Creek study sites to establish relations between continuously measured water-quality parameters and discretely collected water-quality constituents in Stone and Graham (2014). Nutrient models differed among sites, and explanatory variables included turbidity, streamflow, and a seasonal variable.…”

“…A combination of total, particulate, and dissolved nutrient models were used to calculate 15-minute concentrations of TN and TP for the period July 1, 2011, through June 30, 2013. Model development and selection criteria are discussed in detail in Stone and Graham (2014). Total nitrogen models were used to calculate TN concentrations for the 119th, Tomahawk, and State Line (after upgrade) sites, and TP models were used to calculate TP for 119th and Tomahawk sites.…”