Driven by the rising public clamor about health effects reported by people living near wind farms, officials across the nation and around the world have been called on to assess the veracity of these claims.  This week’s contribution to the rapidly expanding genre of “wind farms and health” literature comes from the Massachusetts Departments of Health and of Environmental Protection.  In contrast to last week’s more comprehensive report from Oregon, the Massachusetts report follows in the pattern of the first two similar literature reviews (one funded by the American and Canadian Wind Energy Associations, and another from the Ontario Ministry of the Environment), in that it focuses solely on direct impacts and previously published research papers.  It also addresses a few of the more recent studies, including those by Pierpont, Nissenbaum, and Rand and Ambrose, generally offering them some affirmations for providing new information worth building on, but finding their results not yet solid enough to base siting policy on.

Except for the sections on these recent papers, there is no place in this report for consideration of actual experiences of people living near wind turbines, despite the presence of a neighborhood full of folks in Falmouth who were no doubt ready and willing to share their stories.  From what I’ve heard from these folks, they would offer cogent, detailed, and level-headed testimony about their experiences.

While I can understand why an expert panel might choose to focus only on published material (to avoid the quagmire of trying to assess the veracity of individuals’ reports), and I give the Massachusetts panel due credit for not artificially limiting itself to papers published in peer-reviewed journals, they dropped a crucial ball in neglecting to even mention the word “indirect” in the course of their 164 page report on health effects, let alone provide any sort of acknowledgement or analysis of the ways that annoyance, anxiety, sleep disruption, and stress could be intermediary pathways that help us to understand some of the reports coming from Massachusetts residents who say their health has been affected by nearby turbines.

While the report’s conclusions

that sound levels near turbines are unlikely to directly affect neighbors’ physiology or trigger widespread health degradation is indeed largely supported by the literature, the report also affirms that there is evidence that annoyance and sleep disruption can occur in response to noise levels common around wind farms.  If the authors of the report took the logical and necessary next step, they would examine how these predictable impacts on neighbors may contribute to the health issues being reported.  By implying that those struggling with headaches, concentration issues, or sleep disruption are either making it up or psychosomatic, it only creates more hostility and animus, which will in turn foster increased anxiety and concern about future projects, continuing and perhaps deepening a cycle that may in fact be a key factor in spurring the indirect stress-related pathways that can create effects such as those being reported.

It’s worth stressing that even most of the more cautionary researchers are finding that while wind turbine noise can trigger annoyance and a reported decrease in quality of life for many residents, overall ratings of physical health generally do not differ between those near turbines and farther away.  Robert Thorne (Australia), Carl Phillips (IL), and Daniel Shepherd (NZ) have all estimated that somewhere between 5-15% of neighbors may be reporting health impacts, while Michael Nissenbaum’s cohort studies in Maine suggest that while those closer to turbines have lower sleep quality and some related mental health/concentration issues, they do not show overall worse physical health. This could suggest that those reporting health impacts are either among the relative few who are more sensitive in some way – to sound, air pressure fluctuations, or annoyance-induced stress.  It also may remind us of the need to separate the equally important, and more widespread, impacts on quality of life and sense of place from the more dramatic but apparently less widespread question of acute or chronic health impacts.

It’s becoming increasingly clear that there is no “one dB limit fits all” solution that will settle wind farm siting controversies; it’s crucial that regulators take the next step, by learning from recent experience in order to better assess how likely it is that annoyance will be widespread in any given community. In communities where the new sound may be easily accommodated, higher noise limits and smaller setbacks work fine (as we find in ranching communities); in places where turbine sound is more likely to trigger negative reactions, the higher annoyance rates may lead to both more complaints as well as more stress and, perhaps, to health effects for some.

While most of the Massachusetts report is just another fairly diligent assessment of the previous literature, worth reading over if you haven’t read other similar documents, a couple things did stand out for me.  The first, and most worrisome, was a table of possible night time noise limits presented as a recommended example of the approach Massachusetts should take (based on a standard used in Denmark).  It’s striking that they propose that while residential areas should have limits of 37-39dBA, sparsely populated areas would be subject to higher noise limits of 42-44dBA.  If these means that a remote farmhouse or cabin would receive less protection from wind turbine noise than a rural or small-town area with small lots and more homes, then the thinking is backwards; it’s in the most remote, rural areas that even moderate wind turbine noise will most dramatically change the sense of place and quality of life; in those areas, a limit of 35dB or less may be necessary.  The other item that stood out was a simple sound contour map, which showed that for homes alongside a line of turbines on a ridge, a setback of at least 740m (just under a half mile) would be necessary to keep noise levels at 40dB; very few wind farms in the US are currently built with setbacks this large.

To download this report and supplementary materials, visit this DEP web page.

A recent Health Impact Assessment published by the state of Oregon covers similar territory, but expands the discussion into consideration of indirect health impacts caused by stress and annoyance, as well as stress-related health impacts triggered by community disruption and contention.  In the wake of the Ontario report mentioned above, some members of the review committee reported that a section on community impacts was omitted, and a local field officer recommended that noise limits below 35dB would be necessary to avoid widespread adverse effects in quiet rural areas.