Point to Non-point Trades Stir Debate about VA and PA Programs

The effects of some nutrient reductions efforts in the Chesapeake Bay area today may not be realized for years due to the varied timeframes it takes nutrients to pass through slow-moving groundwater conduits. Some nutrients released by non-point sources can reach streams in a matter of weeks or months. However, the USGS estimates that it takes, on average, a decade before half of the nitrogen that sinks into groundwater seeps into a stream, and more time for the other half. This 'groundwater lag' raises concerns as some states look at nutrient trading regimes that would allow point to non-point trades, rather than solely point-to-point trades. The Pennsylvania and Virginia trading programs, recently created programs that allow point-to-non-point source trades. Both programs use the Watershed Model, a model for developing reduction strategies to meet annual caps, though the model doesn't directly account for the groundwater lag.

– View the Bay Journal article