The following post is related to the Center’s work on a Health Impact Assessment of a proposed biomass-powered energy facility in the Shenandoah Valley of Virginia.  The facility was proposed as a potential remedy to the issue of nutrient concentration related to trends in livestock production.  Each post in the series describes one particular aspect of interest from the Center’s analysis. 

Water Quality

Water bodies within the Chesapeake Bay watershed have significant impairments. Although the ostensible benefit of large-scale power production is to add energy, the driving factor behind the proposal in the Valley has been managing excess nutrients. Studies by the U.S. Department of Agriculture suggest that fields fertilized with animal manure lose a higher rate of nutrients than fields that are not. Water contaminated by animal waste can have a number of negative health impacts especially for households drinking untreated water, an occurrence that is common in rural areas such as the Valley.

Health Effects of Contaminated Water

Concentrations of nitrates—a nutrient abundant in animal manure—in drinking water are a risk for infants and pregnant women. They are associated with the development of methemoglobinemia, a condition that blocks oxygen transport in the blood system. The common name for this condition is ‘blue-baby syndrome’. As the name implies, children born with methemoglobinemia have a bluish tint to their skin because of the lack of oxygen. This is a serious and potentially life-threatening condition but it is also very rare.

In addition to nutrient contamination, manure used as fertilizer can also contaminate drinking sources with other microscopic organisms such as fecal coliform and E coli. These contaminants can result in gastrointestinal distress and infectious disease if consumed. Finally, the capacity of nutrients to support the growth of noxious algal blooms in water bodies can make areas unsafe for recreational activities such as swimming or fishing.

Contaminants to Valley Well-Water

Samples taken from private wells in Rockingham County estimate that 18.9% of wells have nitrate concentrations that exceed the EPA standard.  This standard is based on the concentration of nitrates that is safe for consumption. In Augusta County, 1.3% of wells were found to be at unsafe nitrate concentrations. Unlike with nitrates, the presence of any coliform or E. coli in drinking water can be sufficient to cause health impacts. About half of the wells sampled in Augusta County and a quarter of those in Rockingham County were contaminated with coliform or E. coli.

Unfortunately, there is a possibility that this could be a bigger problem in the future. Soils have a limited capacity to absorb nutrients before they runoff and as the soils become more saturated, more nutrients can end up in drinking water sources. This is a particular concern if poultry production increases in the future.