Data Graphing Instructions

This graphing tool plots data as either multiple monitoring sites for a single parameter, or multiple parameters for a single monitoring site. This choice is controlled by tabs below: "Plot Sites by Parameter" or "Plot Parameters by Site". The default tab is pre-selected with default choices on initial page load with the last eight days of data.

Choosing the tab 'Sites by Parameter' allows a single parameter to be selected from the 'Parameter' dropdown list. Multiple sites can then be chosen by checking the checkbox. When done, choose a date range (or leave it at the default values) and click the "Plot Chart" button. The data will appear as series plotted on the graph. The other tab "Plot Parameters by Site" works similarly.

Available single option choices on either tab will change the checkbox option which reflect the fact that not every parameter is measured at every monitoring site and vice versa.

Plotted series are listed in the table above the tab interface. In addition to the plotted series, this table shows the 'MAX', 'AVG', and 'MIN' values from the data set used to plot that series.

The 'View & Download Data' tab offers a tabular display of the data and the ability to export that data to a Microsoft Excel spreadsheet.

The unit axis (vertical) dynamically adjusts it's range based on the parameters plotted and the data values over the selected time interval.

When graphing the "Plot Parameters by Site", the y axes (vertical) will display in the following manner:

  • If one parameter is checked, then the parameter unit displays on the single y axis.
  • If two parameters are checked, then the parameter units display as a left and right y axis displaying their individual scales.
  • If three or more parameters are checked, then the parameter units go back to a single y axis and uses the generic label "Unit".

Other Graphing Options

  • You can increase or decrease the graphing date ranges by the length of the current period (number of days selected in the date range text boxes) by an entire period by clicking the icons or .
  • Download the chart and associated series table by clicking the "Download Chart (PDF)" link at the top right corner above the chart image.
  • Under the "Plot Chart" button
  • You can move either date in the date text boxes by plus or minus one day clicking the left or right arrow.
  • The show 'Legend' checkbox controls whether to display the legend at the top of the chart
  • The "Missing Data" checkbox will graph a line connecting the beginning and end points of any data gaps. (This makes it easier to identify periods with missing data, especially when you have multiple series showing on the graph.
  • The small "refresh" button will return to the default graph options and date range.