An impressive array of 76 acoustic monitoring buoys is planned to be deployed in Scotland’s Moray Firth this summer, to listen in on local populations of dolphins, porpoises, whales, and seals.  Scientists from Aberdeen University will place the recording devices up to 70 miles offshore, expanding on work carried out last summer on a smaller scale.  Dr. Paul Thompson, one of the lead researchers, explains: “This will help us get a better understanding of the distribution of particular species. We will be looking at the impact primarily of oil and gas exploration, but also the development of wind farms. During construction phase of these developments, it can be quite noisy and affect marine mammals. It will allow us to get a better understanding of how they use different parts of the Moray Firth and to understand what parts are most important” to each species.  Read more at The Scotsman.

In recent months, several lawsuits and formal complaints have been filed, claiming unlawful nuisance and/or impacts on property values and quality of life near wind farms.  Most recently, sixteen residents sued the Michigan Wind I wind farm and its developers, laying out a series of complaints, including (as detailed in the Huron Daily Tribune):

• Private nuisance from, among other things, sustained and highly annoying audible noise and amplitude modulation in both audible and sub-audible frequencies
• Negligent design of a wind farm, including a noise assessment that estimated only audible noise levels within the dBA range, and did not consider low frequency noise or impulse noise
• Negligent misrepresentation, claiming the wind companies made false representations in board of commissioner and planning commissioner meetings and public hearings when company representatives said the wind farm’s operations would not result in a noise nuisance or cause adverse health effects to adjacent landowners. “(The defendants) were negligent in making these misrepresentations because, as the parties seeking approval to construct a wind turbine farm in Huron County, they had a duty to use reasonable care to provide Huron County and its citizens with both accurate and complete information,” the lawsuit states. The plaintiffs claim the wind companies provided inaccurate and/or incomplete information about the audible turbine noise levels, and no information about low frequency noise, infrasound and/or impulse noise emitted from the turbines.

In Pennsylvania, the Allegheny Ridge Wind Farm settled out of court this week as a lawsuit brought by Todd and Jill Stull was moving toward a jury trial in July.  The suit alleged that the company misrepresented the noise levels that would be generated by assuring residents the noise would e minimal.  The agreement is bound by confidentiality, so no details are available. See earlier coverage of the lawsuit here.

Meanwhile, in neighboring Wisconsin, Read the rest of this entry »

This recording, by one of the wind farm neighbors in Wisconsin who I met when visiting there last fall, is a good, simple taste of the sounds heard from 1500 or so feet away—this one has a predominant jet plane flavor, though often neighbors report a wide variety of sounds that change depending on wind conditions.  Most of these folks have several turbines around their homes; one person told me that he thought he could live with it if the ones closer than a half mile were not there, though another of his neighbors leaned more toward a mile as his comfort zone.  Listening to this selection of sounds, recorded with different cloud covers and wind directions, I could get a sense of why some people find hearing this incredibly disruptive and intrusive, while others say they are not much bothered; this disparity of reaction is one of the fundamental paradoxes of wind farm noise issues.  

Give a listen…..turn it up and down to get a feel for it at different sound levels or distances (or to simulate how it feels to people with different degrees of sensitivity/attention to the sound)…..imagine it lasting far longer than this three minute taste—which may well make it more torturous, or might allow it to sink into the background of your awareness…..if this sound, at a moderate level, or turned down very low to be just audible, was happening in your neighborhood, how would it be for you?

Over the past week or so, two reports from Ontario have spurred a fair amount of notice and comment among those following wind development issues.  First, the provincial health office responded to the public’s concerns about health problems reported by some wind farm neighbors, framing its answer carefully and narrowly:  “According to the scientific evidence, there isn’t any direct causal link between wind turbine noise and adverse health effects,” said Dr. Arlene King, Ontario’s Chief Medical Officer, as reported by the Vancouver Sun.  Since the report’s focus was to asses peer-reviewed science, its authors did not incorporate any reference to the experiences or changes in sleep patterns or health of real-life neighbors of wind farms who have reported negative impacts since the turbines began turning. It is no real surprise that the sound levels near wind farms aren’t loud enough to directly cause physiological damage or effects, though it seems clear that annoyance and sleep disruption may well contribute to health effects in some people; the report acknowledges the likelihood of some annoyance, and notes too that while low-frequency sound is below generally perceptible levels, and generally no louder than naturally-occuring low-frequency sound sources, some people who hear these frequencies better than most may be bothered.  While the report itself is brief and lacks the detail of the recent industry-funded AWEA/CanWEA report, which reached similar conclusions in addressing the same narrowly-focused questions, King’s report frames the results with two crucial but under-reported observations:

• By way of introduction, the report explicitly states a simple fact that is rarely acknowledged: “Little information is available on actual measurements of sound levels generated from wind turbines and other environmental sources. Since there is no widely accepted protocol for the measurement of noise from wind turbines, current regulatory requirements are based on modelling.”  Indeed, sound models are used to determine what distance a turbine needs to be from nearby homes in order to meet local statutory noise limits (which stand at 40dB in Ontario).
• And in its final words, the report stresses the corollary to this observation: “The review also identified that sound measurements at residential areas around wind turbines and comparisons with sound levels around other rural and urban areas, to assess actual ambient noise levels prevalent in Ontario, is a key data gap that could be addressed. An assessment of noise levels around wind power developments and other residential environments, including monitoring for sound level compliance, is an important prerequisite to making an informed decision on whether epidemiological studies looking at health outcomes will be useful.”

Actual rural ambient noise levels are often very low, so that wind farm noise becomes bothersome at lower levels than industrial or transportation noises prevalent in urban and suburban areas; and, as noted in the body of the report, most of the case studies and other reports of health effects lack any clear information on how loud the turbine sounds are in the homes of those being affected.  So while this report is in large part another seemingly definitive, yet stubbornly partial, assessment of the health effects reported near wind farms, it also lays the groundwork for much-needed on the ground assessment of noise patterns around wind farms. (See this more recent post, regarding a section on community health and disruption that was omitted in the final draft of this report.  And see this critique of the CMOH report, written by several doctors from Canada, the UK, and the US who have been advocating for closer study of these issues)

On a similar note, Ontario Ministry of Environment officials confirmed this week that they do not have the capability to record or assess the noise near wind farms where noise complaints arise.  According to the Windsor Star, “Although hundreds of wind turbines have already been built in Ontario, Michael Parker, district manager for the environment ministry, said staff have not yet been given noise-monitoring equipment. The ministry is responsible for ensuring that wind turbine noise reaching a residence doesn’t exceed 40 decibels, he said.  If a complaint about turbine noise is made to the ministry, two environment officers are sent to the area to listen for the noise and contact the turbine owner, Parker said, noting that the ministry could still intercede with turbine owners even without hard data on the noise levels. In some cases, turbine speeds have been scaled back or the turbine shut down completely.”  In January, the Ministry of Environment issued two Requests for Proposals seeking advice and technical standards to use in assessing wind farm noise. The RFPs said that “The Ministry requires a consultant to assist in the development of a measurement procedure to assess noise compliance of existing wind farms with the applicable sound level limits,” noting that “Unlike typical industrial noise sources, measurement of audible noise from wind turbines in general raises technical challenges.” At that time, the Ministry acknowledged that its “Noise Guidelines for Wind Farms…do not contain a measurement method for assessing the actual noise impact.”

The Morrow County Planning Board ruled this week that the Willow Creek Energy Center, an 80-turbine wind farm, is producing noise levels that violate Oregon’s noise limits, and gave Invenergy, the wind farm’s owner, six months to get the turbines into compliance.  The wind farm began operating in January 2009, and by March, several neighbors within a half mile had raised serious concerns about the noise (see this article for details), including regularly having difficulty sleeping. Noise monitoring then took place, and in January of this year, the Planning Board received the results, which showed that noise levels at four homes sometimes exceeded the limit of 37dB.

There was some contention at that meeting, as neighbors had hired independent noise monitoring consultants, whose records showed more consistent violations than those of the Invenergy-hired consultant; the differences were pegged to the fact that the Invenergy consultant did not record in high wind speeds, contending that the noise gets no louder above wind speeds of 9m/s.  It is unclear from initial news reports whether the wind farm will be required to comply with the noise limits based on the Invenergy sound monitoring protocol, which found excess noise just 10% of the time at one house, and less frequent slight violations at three others, or whether they’ll use the more comprehensive techniques used by the local citizens, which found violations more consistently at two homes (one just over the limit, the other often over 40dB), with one home experiencing excess noise on 22 out of 37 nights.

Carla McLane, Planning Director for Morrow County, noted that while the commission did rule the wind farm was violating state regulations, it found the turbines only crossed the noise threshold at certain times of day and under certain conditions. “Some would want to view it in black and white and if it’s a violation then you have to shut them down,” McLane said.  “Others would want to view it in terms of shade of gray and say it’s not an ongoing and continuous violation. It’s an intermittent violation.”

”I’m not sure how someone can say this is an unusual, infrequent event,” said Kerrie Standlee, one of the neighbors’ noise consultants. “To me, 59 percent (of nights with excess noise) is not occasional or unusual.” Standlee’s noise study also went beyond Invenergy’s in that he gave the residents a sheet of paper to log their experiences with time and date. He then overlaid those comments on the data and showed that when the residents reported high noise, the wind was blowing from a particular direction or at a particular speed.  This last bit of information may offer Invenergy some direction about when they might shut down turbines if they want to avoid the worst of the noise issues, during the six months they have to get into compliance.

The Planning Board struggled with the conflicting approaches, according the the East Oregonian (article archived here). “I have a very hard time coming to a concrete conclusion on which study I feel is accurate,” Commissioner Pamela Schmidt said. “I’m not a licensed engineer in acoustics myself and there’s been so much information I can’t make a decision.”  Invenergy claimed that the background ambient noise varies, so that in higher wind periods, it should be allowed to exceed 36dB; yet, in its permit, it used the 26dB ambient standard, which is the state’s default if measurements are not made ahead of time. Complicating matters more is the fact that, as the East Oregonian noted, “the rule does not direct agencies on how to administer the rule or decide conflicts such as the one between Invenergy and its neighbors. The agency that originally enforced the rule, the Oregon Department of Environmental Quality, has since defunded and destaffed its noise program.”

It’s worth noting that the noise issues seem to be quite pronounced even at sound levels of 40dB.  Oregon’s 36dB limit is among the most conservative in the country; it’s based on being 10dB above average night time ambient noise levels, which have been measured at 26dB.  It appears that noise issues may well be present even when the measured sound levels are at or very near 36dB; this is in synch with reports from elsewhere, which suggest that people accustomed to quiet rural night time soundscapes are quite easily disturbed when turbine noise becomes one of the loudest local sounds, even when absolute noise levels are not extreme. In general, acousticians consider a sound to become readily audible when it is 5dB above ambient, with disturbance considered likely when it reaches 10dB above ambient.

UPDATE, June 2011: The state Land Use Board of Appeals issued a ruling that questioned the county’s interpretation of the 36dB noise limit. In its ruling, LUBA sided with the wind developer, which had said that the state laws allow wind farms to produce up to 10dB more than ambient sound levels; the county had been suggesting that if the developer doesn’t conduct ambient noise studies before construction, they must assume ambient of 26dB (typical night time ambient).  The LUBA decision said that this requirement to choose whether or not to do an ambient study prior to construction did not appear in the state rules, leaving room for companies to show later that measurements of turbine noise levels exceeding 36dB were  made when the ambient was above 26dB.

A private landowner in Clifton, Maine, is hoping to erect four commercial wind turbines on a small ridge known as Pisgah Mountain, and sell the energy to the local utility, Bangor Hydro.  Hearing of negative experiences in other Maine towns, including Mars Hill and Vinalhaven, some local residents are concerned about noise impacts and effects on wildlife.  The town of Clifton has drafted a new ordinance that sets 4000 feet as the minimum distance between a turbine and a neighboring house; this ordinance will go before voters on June 8.  In both other towns, affected families live within 3500 feet of the local turbines.

“What we have on this site is setbacks to the closest residence of a little over 4,300 feet,” says Paul Fuller, who owns the 240 acres where the turbines would be built. “I think we could boast that that is the farthest setback of any wind farm in the state of Maine at this point.”  Several other homes are within a mile to mile and a half of the location.

If this project moves ahead, it would be one of the first to do so with regulatory setbacks of over 1500-1700 feet, which are commonly used in Maine and elsewhere in the US, as developers aim to reach a 45dB limit at homes.  The ordinance allows sound levels of up to 50dB during the day and 40dB at night; past experience would suggest that at this distance, these sound levels are unlikely to be reached, though it is entirely possible that the turbines will be somewhat audible up to a mile or so away at times (night time noise levels in rural areas can be as low as 20-25db).  Some community advocates urge setbacks of a mile or mile and a quarter, to more surely eliminate audible noise issues; this project would be a valuable “guinea pig” for the helping answer the crucial question of where the proper balance lies between wind development and respecting the rural soundscape of small towns.

Read more and see a news clip at WLBZ2.com

If you’re within easy reach of the Bay Area, here’s an annual event that is always fun, intimate, and rewarding:

Excite your ears—explore nature sound recording and natural quiet at the Nature Sounds Society’s 26th annual field recording workshop

The workshop will be June 25-27 at San Francisco State University’s Yuba Pass Field Station, in the beautiful Sierra Nevada Mountains. This year’s theme is “Vision of Sound.”

Featured speakers at this year’s workshop are “The Sound Tracker,” Gordon Hempton, Emmy award-winning nature recordist and author of One Square Inch of Silence and the subject of a new documentary film, Soundtracker, by Nick Sherman. Hempton and Sherman will present the film at the workshop. The program also includes John Muir Laws, illustrator, naturalist and teacher, author of The Field Guide to the Sierra Nevada and the new Laws Pocket Guide; director Gina Farr of Farr Visions and the creator of Wild Sound Stories; and Dan Dugan, renowned sound designer. Each guest has a unique point of view of the natural world and vividly expresses him or herself through art, environmental activism and education. As an additional option, participants may choose to take an overnight backpack on Sunday June 27th to a recording location free from mechanical sound, organized by Steve Sergeant of the Sierra Club.

The “early bird” (prior to June 1) cost of the workshop is $175 for NSS members, $200 for non-members, and includes a one-year NSS membership. After June 1, the cost is $200 for NSS members and $225 for non-members. Lodging in tent cabins and meals are included. The optional Sunday night backpacking expedition will be an additional cost.

For more information, contact the Nature Sounds Society at (415) 821-9776 or e-mail Dan Dugan

Nature Sounds Society: http://www.naturesounds.org

The Spring 2010 issue of Currents, the quarterly magazine published by N45, the Navy’s environmental readiness division, features a long article on recent research by Ted Cranford of San Diego State University, which is revealing new details about the anatomy of beaked whales.  Cranford has developed an innovative technique to use x-ray CAT scanners designed to scan rocket motors, and with the data garnered there, is working with an expert in Finite Element Modeling (FEM) to model the ways that sound moves through and around the jaws of beaked whales before reaching their ears.

The results are not all that surprising, in a big-picture way: indications are that the whales’ auditory system filters sounds so that frequencies used in communication and echolocation are accentuated, with other frequencies dampened.  The frequencies used by mid-frequency active sonar, which are near the low end of beaked whales’ auditory range, are filtered by the sound transmission path, so that they impinge on the ear at levels 6dB or more lower than they arrived at the whale’s jaw.

The article doesn’t specify the sound levels used in the tests, to help us compare these results to what animals experience at sea. However, the captions and text repeatedly frame the results to mean that mid-frequency sonar is “largely filtered out before reaching the ear.”  The implication that a 6dB, or even greater, dampening largely removes the signal seems quite misleading; rather, only near the very faintest received levels that would be heard will the dampening render them inaudible.  It’s unsurprising that these frequencies are not of inherent interest to the whales, and it’s reassuring that their anatomy may help protect them from direct physiological damage by such sounds.  But clear behavioral responses to mid-frequency active sonar signals tell us that they clearly hear them, and respond more dramatically than most others to these sounds.  Perhaps these test results could also suggest that beaked whales are especially sensitive to sound in general, or to these sounds at the low end of their audible frequency range; for example, harbor porpoises are well-known to react to quieter sounds than many other species, and recent research has shown that they experience temporary hearing loss (TTS) at lower levels as well.  We may be simply learning that when beaked whales are exposed to, say, 160dB sonar signals, their bodies reduce the sound levels to 150dB by the time it reaches their ear–but they still react, even to this reduced sound.

While the new research is fascinating in its own right (and will be even more compelling if ongoing current research validates the modeling being used), it seems that the Navy needs to be careful in how they present the implications.  To imply that beaked whales are “largely filtering out” sonar sounds is no more helpful in fostering informed public and scientific dialogue than the perception that mid-frequency sonar is a “death-ray” for whales.

Currents is well worth following.  Each issue has a column by the Director or Assistant Director of N45, and about twice a year they run extensive features on various ocean noise topics:
Currents main web site
Spring 2010 feature on Ted Cranford’s research
Winter 2010 feature on Dave Moretti and the Navy’s Marine Mammal Monitoring program, including various tagging programs (Dave raised the “death ray” perception in his interview)
Winter 2009 feature on the Navy’s Marine Mammal Science program

England’s primary environmental agency, the Department for Environment, Food, and Rural Affairs (DEFRA), has commissioned a study to improve techniques for assessing wind farm noise.  “There is a possibility that local authorities are not currently investigating complaints about noise from wind farms due to the absence of any formal technical guidance,” an internal document reads. “Defra wishes to let a contract to provide local authorities with a methodology by which to investigate noise from wind farms, to support local authority enforcement of statutory nuisance legislation.”  According to the Telegraph, the report is due out later this year, and should make it easier for local councils to respond to noise complaints.  A recent survey suggests that about one in seven UK wind farms have spurred noise complaints; noise campaigners contend that many people who are bothered do not file formal complaints, since they are rarely acted upon.

(UPDATE, 8/2/10): Apparently, the news report cited above was about a call for proposals, or plans to let the contract; in August, Energy Minister Charles Hendry announced that the consulting firm Hayes McKenzie had been hired to conduct this review of noise assessment techniques.  The firm will begin work in September and is expected to complete its report by the end of the year.

Meanwhile, also in the UK, the Bradford Planning Inspector upheld a ruling by the city Council to deny a permit for building a single large turbine at a factory in town.  The applicant had appealed the denial, since its noise studies showed that that the turbine would be in compliance with the federal noise code ETSU-R-97, which is the only code named in the statutes.  However, the investigating Bradford Council Environmental Health officer used several other noise level methodologies when he visited a similar turbine in Norfolk. Using World Health Organisation and British Standard guidelines and codes of practice, as well as ETSU-R-97, he came to the conclusion that the Princes Soft Drinks turbine would cause a noise nuisance for nearby residents. The Planning ruling noted that even according to the company’s modeling, “for some dwellings under certain conditions, the emitted turbine noise is likely to lead to complaints. Furthermore, according to WHO standards, there would be times when this noise could result in sleep disturbance, or prove to be a serious annoyance to residents. I find this to be unacceptable.”

Councillor John Ruding said: “I am delighted that the inspector agreed with the local community and their voices have been heard. “These proposals were an experiment on people’s lives which was not acceptable.”  Earlier, at the time that the company appealed the initial denial, another Councillor, James Cairns, had noted, “The Council has done its best. Its officers didn’t believe it was feasible in the area. Bradford is not against wind turbines – if you go up onto the moors, you will see them. But turbines of this size have not been tried and tested in urban areas.”

The Center for Biological Diversity has filed a 60-day notice of intent to sue the Department of Interior, claiming that the Minerals Management Service (MMS) has been approving oil and gas exploration and development for years without making the companies obtain the “incidental harassment permits” required by the Marine Mammal Protection Act and Endangered Species Act.  While the CBD’s press release focuses on the 100 seismic surveys and 300 drilling operations approved since the Obama administration came into office (and uses some pretty inflammatory language aimed at Secretary of Interior Ken Salazar), the Gulf has been one of the world’s most industrialized ocean regions for many decades, and the practices described are long-standing.  According to the CBD press release, the primary impact that has not been addressed is the effects of industry noise on whales and other sea life; CBD point out that some of the sounds are loud enough to damage whale hearing (though fails to note that this occurs only at very close range) as well as disrupt important behaviors (which can occur many miles away). The North Sea is the only other ocean region that’s been so widely impacted for so long by oil and gas development, with West Africa, Brazil, Indonesia, and the South China Sea all working hard to join the party in recent years.

The CBD stresses that the many oil and gas activities in the Gulf must be more thoroughly examined, especially since in some conditions noise can reverberate and become nearly continuous.  While the National Marine Fisheries Service was consulted by the MMS, with NMFS issuing a Biological Opinion that included the assessment that whales would be affected, no harassment  or  permits were issued or required by MMS. (Ed. note: I haven’t read the Biological Opinion, but there’s a good chance that NMFS considered the effects to be negligible; this is a common bottom line in agency consideration of noise impacts, and is the grounds used to issue the harassment permits.  It is likely that while CBD’s suit is based on the procedural question of missing permits, the root of their challenge is a disagreement that the effects are negligible.) The notice of intent concludes by saying: “An appropriate remedy that would prevent litigation would be for the Secretary to initiate the process to authorize the take of marine mammals in the Gulf of Mexico pursuant to Section 101(a)(5) of the MMPA by a date certain. Meanwhile, the Secretary must stop approving lease sales, exploration and development plans, and seismic exploration permits in the Gulf of Mexico until and unless it obtains the required authorizations under the MMPA and ESA.”

UPDATE: According to a Reuters report, the Interior Department and the White House Council on Environmental Quality (CEQ) announced on Friday the 15th that they would initiate a review of MMS’s NEPA procedures, especially their obligations under the MMPA and ESA.  Earlier in the week, Secretary Salazar had announced a plan to split the MMS into two parts, one of which would collect royalties, with the other overseeing regulatory enforcement.

When the town-owned wind turbine began operating at the Falmouth, MA wastewater treatment facility in March, most townspeople saw it as the most striking example of the town’s far-reaching commitment to sustainability.  Since then, it’s generated about a third of the town’s electricity needs, and a second turbine is being readied for installation nearby this summer.  As noted at a forum on the town’s many energy-savings initiatives, in discussing the second turbine: “The special thing about the site is it’s remote. The nearest home is about 1/3 mile away, which is important in terms of noise and appearance.” (This is just under 1800 feet, or 600 yards.)

But over the few weeks since the first turbine began operating, residents are finding the noise much more disruptive than they’d imagined.  According to the Cape Cod Times, some neighbors who live in the sparsely populated, wooded area around the treatment facility were horrified when they heard the noise. “It’s destroyed our capacity to enjoy our homes,” Kathy Elder said. Elder said the noise surrounds her residence, alternating between a jet’s whine, thunder and a thumping that sometimes can be felt.

The town has received formal complaints from six residents, one of whome, Annie Hart Cool, has gathered over 40 names of people within a mile or so who say they are affected.  She notes that her husband enjoys working in their yard after work, “but when he comes back inside and his head is hurting, you know something’s wrong.”

Assistant Town Manager Heather Harper says that the town has asked Vestas, the turbine manufacturer, to come check whether there are any mechanical issues that may be causing elevated noise levels, and is asking residents to compile records of when the sound is worst, to help the town figure out how to respond. “This has been a community project from the beginning,” Harper said. “We’re genuinely concerned and we take the complaints very seriously.”  At the same time, Harper noted that “We didn’t expect no sound, but it should meet all governmental standards.”  This is, indeed, often the issue: governmental noise standards, which tend to range from 40-50dB, are not always sufficient to avoid negative impacts on the nearest neighbors.

UPDATE: Another local newspaper covers the brewing controversy.

An excellent 3-part series on wind farm development ran this week in the Bismark Tribune. It has a good balance of the excitement and economic benefits that attract farmers to the industry, and well-stated concerns from those who want larger setbacks in order to protect neighbors from noise.  The grey area around health impacts is navigated quite well, with a well-grounded emphasis on sleep disruption; and most strikingly, the piece includes acknowledgement that there is individual variability in how easily people can adapt to a new and potentially intrusive noise source.

Interestingly, there are repeated indications that in this community, as in others, a half mile setback was seen as the “sweet spot” that could accommodate both industry and neighbors; in initial community meetings, there was significant support for a one-mile setback, while a general consensus emerged that a half mile would be tolerable to most people.  Nonetheless, the county decided to go with a third of a mile (1750-foot) setback, which has some community members concerned that the turbines will be audible enough to be disruptive at times.