Data readings are collected at the super gage sites every 15 minutes via satellite, transmitted hourly, and processed into a national database. The data is uploaded to a national server that publishes the data to the public, making it real-time.

View Current Data!

Real-time water quality (RTWQ) refers to in-stream water-quality measurements made available on the web in real-time. Providing these data in real-time informs the user of stream conditions for various uses and public safety.

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Science Center Objects

 

 What is a Super Gage?

A gage at which continuous flow and water level are determined, along with continuous traditional water-quality (water temperature, specific conductance, pH, dissolved oxygen, and/or turbidity) and either of the following criteria:

  • at least one other less-traditional continuous water-quality parameter (orthophosphate, nitrate concentration) 
  • and/or where surrogates (developed from regression models) which are used to esitmate time series concentrations of constituents (such as suspended sediment, total nitrogen or total phosphorous).
Real-Time, Continuous Water-Quality Monitoring in Indiana and Kentucky Fact Sheet

Super Gage

Super gages provide real-time data specifically designed to improved our understanding of watershed processes and to address specific water-resource issues such as climate and land-use effects, water-related human health issues, floods and droughts, or hazardous substance spills. Our ability to model estimates of continuous data (sediment surrogates) and continuous nitrate data help improve estimates of loads to downstream critical areas such as the Gulf of Mexico and the Great Lakes.

Continuous concentrations can be used to determine continuous loads (mass transportover time) of key nutirents pr sediment. Concentration and loading data are updated hourly on the web and display intervals of 15 minutes to 4 hours. 

Super Gage Types

Super gages differ by the type of equipment deployed and available modeled constituents. Additional data, such as precipitation or water-quality samples, also may be collected. The specific site page lists all available data for each station.

 

Type Water-Quality Parameters
Continuous water temperature, specific conductance, pH, dissolved oxygen, and/or turbidity
Nitrate water temperature, specific conductance, pH, dissolved oxygen, turbidity, nitrate plus nitrate
Nitrate and Modeled Constituent water temperature, specific conductance, pH, dissolved oxygen, turbidity, nitrate plus nitrate, modeled constituent
Nutrient water temperature, specific conductance, pH, dissolved oxygen, turbidity, nitrate plus nitrate, orthophosphate as phosphorus
Nutirent and Modeled Constituent water temperature, specific conductance, pH, dissolved oxygen, turbidity, nitrate plus nitrate, orthophosphate as phosphorus, modeled constituent
Sediment and Modeled Constituent water temperature, turbidity, modeled suspended sediment

 

Water-quality equipment from supergage Ohio River at Olmsted KY

What types of equipment do we use in a super gage?

  • Water-quality sondes
  • Ultraviolet nitrate sensor
  • Automated phosphate analyzer

How do we know the super gages are functioning correctly?

We do representative stream-width and depth-integrated sampling to verify the super gage data and to collect data for surrogate models.

What's a surrogate model?

"Surrogate" Constituent Models are developed at USGS streamflow gages, called Super Gages, throughout Ohio, Kentucky, and Indiana. Each Super Gage deploys a variety of in-situ continuous water-quality monitors and is intermittently sampled for water-quality constituents over the range of hydrologic and seasonal conditions. By statistically combining continuous water-quality data with intermittent samples, models are developed to continuously estimate constituents that are not easily measured in real-time. For example, after a Surrogate Constituent Model is developed, turbidity (clarity of water) may be used to estimate suspended sediment concentration. Click here for a list of Ohio-Kentucky-Indiana Water Science Center Surrogate Constituent Models.

We develop surrogate models by

Mega-gage at Kankakee River at Davis, IN

  • comparing in-stream values to discrete values then
  • develop a regression model to estimate concentrations during non-sampled periods.

From the surrogate model, we get computed or estimated concentrations of a constituent of greater interest.

Many states provide hourly computed concentrations and loads for sediment, nutrients, bacteria, and many additional constituents; uncertainty values and probabilities for exceeding drinking water or recreational criteria; frequency distribution curves; and all historical hourly in-stream sensor measurements.

 

 Want to Know More?

View the station data and more information for each site.

Surrogate Constituent Models

Surrogate  Constituent Models

"Surrogate" Constituent Models are developed at USGS streamflow gages, called Super Gages, throughout Ohio, Kentucky, and Indiana. Each Super Gage deploys a variety of in-situ continuous water-quality monitors and is intermittently sampled for water-quality constituents over the range of hydrologic and seasonal conditions. By statistically combining continuous water-quality data with intermittent samples, models are developed to continuously estimate constituents that are not easily measured in real-time. For example, after a Surrogate Constituent Model is developed, turbidity (clarity of water) may be used to estimate suspended sediment concentration. Click here for a list of Ohio-Kentucky-Indiana Water Science Center Surrogate Constituent Models

National Current Water Quality

Many states provide hourly computed concentrations and loads for sediment, nutrients, bacteria, and many additional constituents; uncertainty values and probabilities for exceeding drinking water or recreational criteria; frequency distribution curves; and all historical hourly in-stream sensor measurements.

USGS National Water Quality Web Site

Ohio-Kentucky-Indiana Water Science Center regression models are listed in the table below. The list of these models also is available as a Microsoft Excel spreadsheet.

 

Data Sampled
Concentration
Rangea
Regression Model Explanatory
variable
range
(FNU)b
RMSE R2 n Bias
correction
or smear
factor
NRTQW
web sitec
Date
Model
Approvedd
Start End Start End
Yellow River near Oak Grove, IN (USGS Site ID: 05516665)
2012 2013 1-169 log10(SSC)=0.7856*log10(TURB)+0.5645 0.8-130 0.157 0.83 22 1.0632 2014 present 8/19/2014
Yellow River at Knox, IN (USGS Site ID: 05517000)
2012 2013 14-1050 log10(SSC)=1.2269*log10(TURB)+0.0854 9.7-160 0.21 0.84 17 1.1146 2014 present 8/13/2014
Yellow River near Brems, IN (USGS Site ID: 05517010)
2012 2013 4-1150 log10(SSC)=0.745+(0.191*sqrt(TURB)) 0.3-150 0.18 0.91 27 1.083 2015 present 8/27/2014
White River at Hazleton, IN (USGS Site ID: 03374100)
2010 2011 16-434 log10(SSC)=0.968*log10(TURB)+0.330 9-170 0.08 0.96 13 1.015 2014 present 2/21/2012
Eagle Creek at Zionsville, IN (USGS Site ID: 03353200)
2010 2014 4-903 log10(SSC)=0.7837*log10(TURB)+0.6015 2-460 0.26 0.77 37 1.1722 2014 present 5/20/2015
Kankakee River at Davis, IN (USGS Site ID: 05515500)
2013 2015 1.2-130 SSC=14.362*sqrt(TURB)-8.662 7-161 8.74 0.94 20 NA 2016 present 03/7/2016