Stories in Water Data

The map below depicts five non-tidal stations in the Susquehanna River Basin. Each map point includes a chart and watershed locator map on the left panel. The top row on each chart shows discharge, the middle row shows nitrogen load, and the bottom row shows phosphorus load. Click on the arrow on the right of the chart to view a locator map of the monitoring site watershed or drainage area.

• The Stations at Chemung, NY and Newport, PA; i.e., stations that have the smallest drainage areas, also had the smallest discharge and loads.

• The Marietta, PA station has the largest drainage area and it also had the largest discharge and loads.

• The drainage area at Lewisburg, PA is about twice the size of Newport, PA’s and only a little smaller than Towanda, PA’s, but its phosphorus load was almost the same as Newport’s and much lower than Towanda’s.

• The highest nitrogen load lined up with the highest discharge at all stations, but …the highest phosphorus load did not necessarily line up with the highest discharge at all stations.

The highest discharges were in:

• April 2017 for Chemung, NY and Towanda, PA (the northernmost stations);
• September 2018 for Lewisburg, PA and Newport, PA; and
• November 2018 for Marietta, PA.

• The lowest discharges were in September 2020 for each station, except Newport, PA, which had its lowest discharge in July 2016.

• There's a very big difference between the highest and lowest discharges and loads at all stations.

Robert Hirsch and colleagues working for the Chesapeake Bay Program developed a generalized flow normalization model for sorting through lots of measured and forecasted data to look for trends. Their model filters out the complicating aspects that time, discharge, and season each add when looking for trends.

The following charts show WRTDS flow-normalized trends for loads and concentrations of nitrogen and phosphorus at the Lewisburg, PA station on the West Branch Susquehanna River. 

...but, most of our society does not resemble natural conditions.

One question you may still be asking is what actions are taken to reduce pollutant loads and improve water quality?

There are many more examples of management actions such as stabilizing eroded stream banks, reducing or eliminating fertilizers, and using cover crops.