Cover crops not as effective as billed?

Cover crops like this and other "best management practices" to control farm pollution may not be as effective as regulators give them credit, according to the Environmental Integrity Project, a Washington group. (Glen Fawcett, 2008 / July 14, 2014)

Federal environmental officials may be overestimating farm pollution reductions in the Chesapeake Bay, contends a Washington environmental group, which also finds that phosphorus and algae concentrations in rivers on Maryland's Eastern Shore have shown no real improvement over the last decade

Those are the conclusions of a pair of reports released Monday by the Environmental Integrity Project.

State monitoring data showed no reduction in phosphorus levels in eight waterways on the Shore from 2003 to 2013, while concentrations actually worsened in three rivers: the Nanticoke, the Sassafras, and the Transquaking.

Despite efforts of farmers, EPA and state agencies to curtail polluted runoff from fields, winter cover crops and other “best management practices” may not be working as well as intended, the group contended. Neither the states nor EPA monitor streams next to farms enough to determine how well these strategies are really working, according to Abel Russ, author of one of the reports. It recommends more and better monitoring, especially in water ways surrounded by farmland.

The reports echo in part a recent analysis by the U.S. Geological Survey, which found that phosphorus levels measured farther upstream in most major bay tributaries have shown no improvement in the past decade, and some have gotten worse.

But Scott Phillilps, bay coordinator for the geological survey, said while the data suggest a lack of progress it's not clear that's the case. Meanwhile, he cautioned that increasing stream monitoring to study effectiveness of farm runoff controls may not be enough, because variability in soils and other characteristics may prevent generalizations.