Scatterplots - Software Tools for Better Sewer Flow Metering

Scatterplots are a tool available for use with Marsh-McBirney, Inc. open channel flowmeters that use Flo-Ware software.  Simply put, a scatterplot is an X vs. Y plot of intersecting data points.  Unlike many typical reports of flow data a scatter plot has no reference to date and time.  Rather it shows patterns (or lack of patterns) between two measured parameters within a given set of data.

The scatterplot shown above is based on velocity (Y axis) and level (X axis).  As you can see, there is a well defined pattern that suggests a strong and repeatable relationship between the two measured components.  While this is not a guarantee of adequate monitoring conditions it is a good indicator.  By contrast, a scatterplot that shows data points distributed across the chart in what appears to be a random fashion may indicate a monitoring site with characteristics that defy accurate metering.