Reducing Phosphorus Pollution in Maryland
Phosphorus is one of the three major pollutants affecting the health of the Chesapeake Bay. One of the largest sources of phosphorus is manure. In fact, farm land where manure is applied has, on average, three times more phosphorus runoff than land not receiving manure.
As part of the Chesapeake Clean Water Blueprint, Maryland is required to reduce phosphorus pollution 48 percent by 2025. The state's Watershed Implementation Plan (WIP) includes methods for achieving that goal. One method is reducing the amount of phosphorous applied to fields that have the highest risk of phosphorus runoff, which pollutes the local waters. Enter the Phosphorus Management Tool, a method of identifying the fields that contain the most phosphorous and have the highest risk of phosphorus runoff.
How the Phosphorus Management Tool Works
Phosphorus, like nitrogen and other nutrients, is vital to crops. However, like nitrogen, when there is more phosphorus in the soil than the crops can take up, the excess runs off the field and into nearby streams. Soil can be tested to determine how much phosphorus it contains, and is then classified as having "low," "medium," "optimum," or "excessive" amounts. In addition to how much excess phosphorus is in the soil, the Phosphorus Management Tool takes into consideration the slope of the land, type of soil, and proximity of waters—all factors that affect the likelihood that excess phosphorus will find its way into local waterways.
New Maryland state regulations use the Phosphorus Management Tool to identify hot spots where the soil is saturated with phosphorus and where other factors signify a high risk of runoff. Future applications of manure would be limited in such areas and farmers directed to implement techniques to remove some of the excess.
The Phosphorus Management Tool reflects more than 10 years of research conducted by University of Maryland scientists in collaboration with regional and national experts. Revising and updating the tool is an element of Maryland's Watershed Implementation Plan (WIP), the federally mandated document created by the state to outline specific steps it will take to protect and restore the Chesapeake Bay.
Implementation is Long Overdue
These regulations have been in the works for years, and the Maryland Department of Agriculture already delayed implementation once in response to concerns by some farmers who may be affected. A compromise was reached and regulations were issued in the Maryland Register on October 18, 2013.
Now, a small but vocal group of farmers have called upon their state representatives to delay implementation of these important regulations addressing a major source of phosphorus pollution.
Through our long years of cooperative problem solving with farmers, our devotion to supporting scientifically sound policy changes, and our own experience running Clagett Farm, CBF understands the trepidation some farmers feel toward the new regulations. We have supported cost share programs to mitigate the potential of increasing costs to affected farmers.
However, if we don't begin to put these changes to agricultural practices into action—practices that we know cause a significant amount of pollution to local streams, groundwater, and the Bay—we will fail to meet the goals of the Chesapeake Clean Water Blueprint.