Land-Based Wind Energy Guidelines

The U.S. Fish and Wildlife Service has been working on guidelines to protect wildlife from wind turbine noise emissions for several years. The “Wind Turbine Guidelines Federal Advisory Committee” has submitted recommendations which have been included in a draft document. A quick read suggests that the guidelines are voluntary and that no specific limits on noise levels or changes over background are included in the draft. While the Service “intends that these Guidelines, when used in concert with the appropriate regulatory tools, will be the best practical approach for conservation of species of concern,” it is arguable that voluntary guidelines provide little or no assurance of species protection.

Sound and Wildlife [1]

Turbine blades at normal operating speeds can generate levels of sound beyond ambient background levels. Construction and maintenance activities can also contribute to sound levels by affecting communication distance, an animal‟s ability to detect calls or danger, or to forage. Sound associated with developments can also cause behavioral and/or physiological effects, damage to hearing from acoustic over-exposure, and masking of communication signals and other biologically relevant sounds (Dooling and Popper 2007). Some birds are able to shift their vocalizations to reduce the masking effects of noise. However, when shifts don’t occur or are insignificant, masking may prove detrimental to the health and survival of wildlife (Barber et al. 2010). Data suggest noise increases of 3 dB to 10 dB correspond to 30 percent to 90 percent reductions in alerting distances for wildlife, respectively (Barber et al. 2010 [2]).

The National Park Service has been investigating potential impacts to wildlife due to alterations in sound level and type. However, further research is needed to better understand this potential impact. Research may include: how wind facilities affect background sound levels; whether masking, disturbance, and acoustical fragmentation occur; and how turbine, construction, and maintenance sound levels can vary by topographic area.


As can be seen in the draft document text provided above, the Service acknowledges serious adverse impact potentials yet appears to take the approach of “more research” and using post-construction monitoring to assess wildlife impacts. Since distance set during permitting is the only reliable option for wind turbine noise control at this time, the “post-construction monitoring” advocated by the Service may serve to document adverse impacts on species but provides limited utility for species protection. In plain language, once wind turbines are installed and running, the only way to “mitigate” adverse wildlife impacts is to turn off the wind turbines, degrading the wind facility financial basis (an option likely to be met with vigorous opposition by the facility owners).

Proper siting is essential. “Alternative” energy systems based on solar or wind may work as legitimate power engineering options if positive or net-black cost benefit ratios can be established for production and environmental costs. It is suggested here for reader consideration that impacts on species might be reduced were wind turbines sited near busy urban areas compared to ultra-quiet wilderness and quiet rural areas. However there remain serious and unanswered questions about the health effects of low-frequency pulsations from wind turbines, which grow lower in frequency as wind turbines get larger.

We trust, do we not, that we have learned from our former ignorance of environmental impacts during the past many decades, starting with DDT (Silent Spring, Rachel Carson). The bar is set higher now, is it not, from our having learned that we must be honest, transparent, and un-biased to political and corporate interests that in the past, at least, were uninterested in environmental protections. However, once again, consternation surfaces, as separately, questions have been raised as to possible political bias in the committee itself:

“The new guidelines would harm birds by only giving U.S. Fish and Wildlife Service (FWS) biologists responsibility to review wind projects within new, truncated deadlines, and without the funding to hire the requisite additional staff. The new draft guidelines would also protect fewer migratory birds than the earlier version and move away from DOI’s legal responsibility to protect all migratory bird species, not just ‘species of concern’.”

In addition, the new guidelines remove protections for both birds and people that FWS biologists had recommended in their peer-reviewed guidelines, including:

• Allowing greater latitude in installing overhead power lines between wind turbines, which increases the risk to larger birds such as eagles, hawks, and cranes, instead of burying the lines.

• Removing a recommendation that wind developers address wildfire risk and response planning, something that could be potentially very important, especially in Western communities or areas experiencing drought.

• Removing a recommendation that wind developers avoid discharging sediment from roads into streams and waters, a standard recommendation at construction sites that protects water quality.

• Removing a recommendation to avoid active wind turbine construction during key periods in the life histories of fish and wildlife, such as the nesting season for migratory birds.

Will the Service ensure that political and corporate interests are held at bay during this important process?

Concerned citizens have until August 4 to comment on the current guidelines. Comments can be sent to windenergy@fws.gov.

References:

1. http://www.fws.gov/windenergy/docs/WEG_July_12_%202011.pdf

2. Jesse R. Barber and Kurt M. Fristrup. “Evaluating the Prevalence of Masking as a Causal Factor in Wildlife Responses to Noise” Acoustical Society of America. Baltimore, MD. Apr. 2010.