WRTDS-Why farming pollution is increasing


Please click on the Journal of American Water Resources Association to see the technical article, which describes the new sampling regime adopted by USGS for measuring water quality in watersheds. The Weighted Regression on Time, Discharge, and Season (WRTDS) method has already had a major impact on the way scientist are or should be looking at Chesapeake Bay cleanup. It becomes quite apparent for example that urban cleanup in watersheds on the Western Shore is working while cleanup efforts on the heavily farm dominated Eastern Shore are not working. Not only is the cleanup of Eastern Shore pollution not working but also the rate of pollution has substantially increased since 2000. It is hard not to believe farmers when they claim they have cut back on fertilizer applications particularly so called insurance applications, which were common in the 80’s and 90’s. We cannot be sure of this because MDA the responsible State agency refuses to verify compliance with nutrient management plans. In reading this report I am reminded of a study that I did 10 years ago showing the cumulative effect of unused nitrogen in aquifers. This study confirms that our surface water is feeling the effect of deep aquifer fertilizer applied up to 50 years ago in addition to shallow aquifer nitrogen applied 10 years ago. The importance of the WRTDS method can be seen by looking at the Greensboro graph our reference #43. The line drawn for long-term nitrate is shown at a constant slope of 1.1%. It is very difficult to pick up an 8-year trend using old sampling methods but looking at it with the benefit of WRTDS it is easy to see that indeed a major increase occurred starting in 2000 and the slope changed to 1.8%, a significant increase in the rate of N pollution. More later.

Don K


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: