Nitrogen and phosphorus fertilizers still major threats to streams and groundwater, study finds

Nitrogen and phosphorus from fertlizers remain a serious problem in American waterways, the U.S. Geological Survey announced today. "USGS findings show that widespread concentrations of nitrogen and phosphorus remain two to ten times greater than levels recommended by the EPA to protect aquatic life. Most often, these elevated levels were found in agricultural and urban streams," the agency said.

Patrick Reis of Greenwire writes that from 1992 to 2004, "More streams experienced an increase in nitrogen and phosphorus levels than saw a decline, said Neil Dubrovsky, USGS's chief of nutrient research and leader of the national water quality assessment. Nutrients are also on the rise in groundwater, and an increasing number of wells are drawing from supplies that fail U.S. EPA's standards to protect public health, Dubrovsky said." He also told Reis that conditions in groundwater, which supplies many major public ewater supplies, have probably declined since 2004 and will keep doing so as the nutrients move down the water table. The USGS release is here.