Elevated nitrogen levels in Cape Cod's estuaries result in lower property values, according to a Cape Cod Commission study of water quality on the Cape. An update to the Water Quality 208 Plan 8 years in the making revealed
an estimated one percent increase in nitrogen levels results in a .61 percent decrease in home values. During the study period of 2005 to 2013, scientists discovered nitrogen levels soared by 15 percent.
Experts from the Massachusetts Department of Environmental Protection and the University of Massachusetts Dartmouth studied the hypothesis linking decreased home values to increased nitrogen in the water in the Three Bays area of Barnstable. The scientists included homes within 1000 meters, roughly a ten minute walk, from the water and accounted for differences in macroeconomics-- proximity to the water, condition of the property, etc. They discovered increased nitrogen levels in Three Bays increased by 15.8%.
The study authors claim that had nitrogen increased by 12 percent instead, homes would be valued at between $16,774 to $32,957 more per home in 2013. The entire study area in Three Bays added up to a loss of between $49 million to $86 million.
The single greatest contributor to the nitrogen on the Cape is the septic systems that nearly every property has for on-site sewage disposal, according to the authors. In fact, they claim that 80 percent of the nitrogen is attributed directly to septic systems. The Cape Cod Commission will continue to investigate ways to reduce the damage to the watershed and subsequent decline in property values in the future, the report stated.