Data Centers generate continuous 24/7 low-frequency noise from rooftop HVAC cooling systems. Additionally, industrial grade diesel generators also produce a lot of noise and must be run for maintenance (up to 2 hours a day) and during the duration of power outages (day or night). On June 26, Prince William voted against a data center citing noise on schools.
Low frequency noise passes through barriers and travels farther.
Continuous noise above 35 decibels affects our school children.
Low frequency noise negatively impacts health and quality of life.
No recourse for residents/businesses when noise is exceeded after final construction.
Continuous noise, even at low decibels, is also detrimental to wildlife.
Additive affects of noise not being taken into account.
Hot weather increases data center noise.
Low frequency noise passes through barriers and travels farther. The data center HVACs emit a low-frequency noise that is not absorbed well, meaning it is able to pass through barriers and travel farther. It is a constant low-level hum that our brains can’t tune out. The noise ordinance is insufficient because it only takes into account decibels and not the level of frequency (Hz). See No Noise is Good Noise on how locals, whose homes are nearly the same distance from where the data center will be to Pleasant Valley, are responding. And studies are emerging urging that data centers not be placed near schools. According to the Industrial Noise & Vibration Centre, "low-frequency tones (< c 300Hz) cannot be reduced effectively using conventional silencers or barriers and don't contribute much to dB(A)" and therefore must be analyzed differently. A data center completed in 2023 in Leesburg using the latest equipment and measured noise under 55 dBA still evoked complaints from residents up to 3 miles away.
NYC changed their measuring scale away from dB(A) to dB(C) for low-frequency noise and limits air conditioning systems (including industrial rooftop systems) to “42 decibels"..."at an open door or window of a nearby residence”. https://www.nyc.gov/assets/dep/downloads/pdf/air/noise/noise-code-guide-summary.pdf. Chantilly Premier’s Noise Study demonstrates “40 - 42 dBA at the residential area” can be achieved and can be below the Ambient Noise Level (especially at night).
Continuous noise above 35 decibels affects our school children. The World Health Organization recommends noise levels do not exceed 35 decibels in classrooms for optimal teaching and learning conditions. The American National Standards Institute, which provides design criteria and guidelines for learning spaces, confirms that limit as essential for creating the best acoustic environment for learning. Excessive noise is detrimental to concentration, auditory discrimination and speech perception, leading to reduced academic performance. The effects are magnified for hearing-impaired students, and students who are not being taught in their first language. Data Centers near schools in industrial districts will be allowed to produced 24/7 noise up to 72 dBA. Affected schools: Rachel Carson Middle School, Floris Elementary School, Nysmith Private School, and King Abdullah Academy.
Low frequency noise negatively impacts health and quality of life. Citing studies from around the globe these studies “reinforced the fact that low-frequency noise is a powerful stressor. The most cited effects on human health refer to emotional changes such as annoyance [19,20], agitation, and distraction [2,21,22], in addition to the association of low-frequency noise with cognitive alterations [23], the development of cardiovascular diseases [24,25], sleep disorders [26], and high blood pressure [27], and, more recently, the effects of industrial low-frequency noise on dental wear [28,29].”
No recourse for residents/businesses when noise is exceeded after final construction. The noise ordinance allows for up to two hours a day for generator maintenance but unlimited for emergency operations, and there is nothing to prevent the 2 hour maintenance duration from being exceeded. And as a data center builds out and adds more servers, it needs more HVACs and generators yet there are no requirements to continue to monitor noise after initial construction is complete. Any violation would have to be proved and would result in a minimal fine. Chandler, AZ has implemented common sense changes such as requiring continuous noise monitoring and publishing generator testing schedules. PDCREF2 Chantilly Premier, proffer 29d, commits to noise monitoring after each addition of noise generating equipment.
Continuous noise, even at low decibels, is also detrimental to wildlife. Decades of research documenting the effects of noise on wildlife and plant life (including National Park Service, the National Science Foundation, the Federal Highway Administration and internationally) concludes that continuous noise affects wildlife communication, reproduction and survival, forces many to abandon the area, which then leads to deforestation and alteration of the biodiversity of the area. Research shows that “wildlife responses begin at noise levels of approximately 40 dBA”. Yet the impact on wildlife in the adjacent Resource Protection Area, which will far exceed 40 dBA, is being ignored.
Additive affects of noise not being taken into account. The County does not take into account the cumulative effects of multiple data centers. Route 50 area, west of Route 28, is quickly becoming the County's "Data Center Alley" but there are no mechanisms in place to monitor and mitigate the cumulative effects on Pleasant Valley and the Meadows of Chantilly Mobile Home Park.
Hot weather increases data center noise. During periods of hot weather, the generators require more maintenance periods and increased rooftop cooling fan speeds, exacerbating the noise.
Data Centers generate continuous 24/7 low-frequency noise from rooftop HVAC cooling systems. Additionally, industrial grade diesel generators also produce a lot of noise and must be run for maintenance (up to 2 hours a day) and during the duration of power outages (day or night).
Low frequency noise passes through barriers and travels farther.
Low frequency noise negatively impacts health and quality of life.
The County is relying on incomplete, applicant-provided Noise Study for the data center.
No recourse for residents/businesses when noise is exceeded after final construction.
Post-construction noise proffer only to a single point in the Pleasant Valley residential neighborhood.
Continuous noise, even at low decibels, is also detrimental to wildlife.
Additive affects of noise not being taken into account.
The missing traffic noise study for the warehouse violates the Comprehensive Plan.
Hot weather increases data center noise.
Low frequency noise passes through barriers and travels farther. The data center HVACs emit a low-frequency noise that is not absorbed well, meaning it is able to pass through barriers and travel farther. It is a constant low-level hum that our brains can’t tune out. The noise ordinance is insufficient because it only takes into account decibels and not the level of frequency (Hz). See No Noise is Good Noise on how locals, whose homes are nearly the same distance from where the data center will be to Pleasant Valley, are responding. And studies are emerging urging that data centers not be placed near schools. According to the Industrial Noise & Vibration Centre, "low-frequency tones (< c 300Hz) cannot be reduced effectively using conventional silencers or barriers and don't contribute much to dB(A)" and therefore must be analyzed differently.
Low frequency noise negatively impacts health and quality of life. Citing studies from around the globe these studies “reinforced the fact that low-frequency noise is a powerful stressor. The most cited effects on human health refer to emotional changes such as annoyance [19,20], agitation, and distraction [2,21,22], in addition to the association of low-frequency noise with cognitive alterations [23], the development of cardiovascular diseases [24,25], sleep disorders [26], and high blood pressure [27], and, more recently, the effects of industrial low-frequency noise on dental wear [28,29].”
The County is relying on incomplete, applicant-provided Noise Study for the data center. The applicant provided 3 noise studies after citizen's noted inaccurate or missing information. Each study is different and none take into account the frequency octave band which would more accurately represent the 24/7 noise emitted from the rooftop HVACs and diesel generators. A data center completed in 2023 in Leesburg using the latest equipment and measured noise under 55 dBA still evoked complaints from residents up to 3 miles away. The applicant noise studies concludes that normal operation will result in decibel levels that are within the noise ordinance (which does not consider frequency), yet an independent review of the applicant provided noise study estimates that the noise during normal operations (i.e. without the generators running) will be louder. For example, at “the house at the northeastern end of General Stevens Court that will be closest to the estimated centroid of the data center building to be 55.6 dB(A) from the data center when it is operating normally.”, which is over 10 decibels higher than the applicant noise study for the residential boundary.
No recourse for residents/businesses when noise is exceeded after final construction. The applicant has agreed to perform a pre- and post- construction noise analysis for the data center but there are no requirements to monitor the noise after it is built. The only recourse to residents and businesses after construction, if they can prove it, is a “fine of not more than $1000” – a simple budget item for any large company. Generator maintenance is recommended more frequently in warmer temperatures. The noise ordinance allows for up to two hours a day for generator maintenance but unlimited for emergency operations, and there is nothing to prevent the 2 hour maintenance duration from being exceeded. What recourse is the county providing to protect the residents / businesses when the duration is exceeded? Greater Oaks Homeowners Association in Prince William county has been monitoring the noise from a data center near them and contends that it exceeds the noise ordinance 60% of the time. The Comprehensive Plan, Appendix 12, states “Noise, light and other environmental impacts should be examined to ensure that surrounding uses are not negatively impacted by this higher intensity.” therefore a more complete noise study should be required now, before rezoning and construction.
Post-construction noise proffer only to a single point in the Pleasant Valley residential neighborhood. Question: In regards to the residential boundary, shouldn't the proffer read "at any point within the boundaries of the residential community"? There are elevation changes that may result in residents experiencing different decibels of noise throughout the community, so proffering to just the boundary seems insufficient. Answer: We picked the point closest to the data center noise sources as we have to pick some defined measuring point, so that’s the point we are proffering to. We did not test from every point in the neighborhood.
Continuous noise, even at low decibels, is also detrimental to wildlife. Decades of research documenting the effects of noise on wildlife and plant life (including National Park Service, the National Science Foundation, the Federal Highway Administration and internationally) concludes that continuous noise affects wildlife communication, reproduction and survival, forces many to abandon the area, which then leads to deforestation and alteration of the biodiversity of the area. Research shows that “wildlife responses begin at noise levels of approximately 40 dBA”. Yet the impact on wildlife in the adjacent Resource Protection Area, which will far exceed 40 dBA, is being ignored.
Additive affects of noise not being taken into account. The data center noise study does not take into account the cumulative affects of multiple data centers which there are currently 3 in construction on Rt 50 between Avion Parkway and Stonecroft Boulevard, across the street from this parcel. Why are studies not being performed regarding the cumulative affects of noise from multiple data center within close proximity to each other?
The missing traffic noise study for the warehouse violates the Comprehensive Plan. The County’s Development Review Branch (DRB) “continues to request that a noise study be performed as part of this entitlement phase to identify the anticipated transportation noise levels”, yet this request has been ignored. The applicant has estimated 695 daily trips for the High Cub Parcel Warehouse. This type of warehouse not only stores goods long-term but distributes them throughout the country/world. Think Amazon. 2016 ITE Trip Analysis estimates 62.7% are cars leaving 37.7% as trucks (262 daily – day and night – that’s 1 truck every 3 minutes for a 12-hour period). The warehouse’s hundreds of semi-trucks being routed through Lafayette Business park and within 300 yards of Pleasant Valley homes, all contribute to noise pollution. By ignoring the the DRB, the County is violating the Comprehensive Plan, Appendix 12, “Noise, light and other environmental impacts should be examined to ensure that surrounding uses are not negatively impacted by this higher intensity.”
Hot weather increases data center noise. During periods of hot weather, the generators require more maintenance periods and increased rooftop cooling fan speeds, exacerbating the noise.