Noise Report by C. Vidich Assoc.

Noise Issues Associated with Mega-Warehouses

Prepared for Attorney John Parks

MARCH 31, 2023

CHARLES VIDICH ASSOCIATES Ashford, CT 06278

Contents

Lack of Noise Regulations and Standards ............................................................................................... 2 

Noise Standards for Warehouses ............................................................................................................ 2 

Noise Impacts from Truck Traffic..............................................................................................................2 

Noise Attenuation with Distance .............................................................................................................. 3 

Carrying on Normal Conversations ........................................................................................................... 5 

Noise and the Mountain Laurel Sanctuary ............................................................................................... 5 

Noise and Disease ..................................................................................................................................... 6 Conclusion................................................................................................................................................. 6 

Appendix 1: Intruding Noises Found in Residential Outdoor Noise Environment ................................... 8 

Appendix 2: Nomogram for Calculating Truck Noise Based on Daily Truck Volumes .............................. 9

The proposal to modify the Ashford Zoning regulations to allow a wide range of warehouses and distribution centers raises a wide range of noise considerations that have not been addressed by the applicant. Specifically the noise issues generated by these propose uses fall into two categories; those associated with activities on the 113.7 acre site (note: the Ashford Motel parcel is not included in the applicant’s zoning text change request but is part of the project area) and those associated with off-site noise impacts associated with increased truck and employee traffic.

Lack of Noise Regulations and Standards

Neither the Ashford Zoning Regulations nor any of the municipal ordinances establish noise standards. This creates a vulnerable situation for Ashford residents when there are no standards to determine what are acceptable or unacceptable levels of noise. With the passage of Public Act 22-143, Ashford is authorized to establish noise regulations without the approval of the Connecticut Department of Energy and Environmental Protection (CTDEP). Sixty six municipalities in Connecticut have adopted noise ordinances and these could serve as models for the Ashford Planning and Zoning Commission.

Noise Standards for Warehouses

The CTDEEP requires industrial uses to not exceed 61 dB(A) during the daytime hours and 51 dB(A) in the nighttime. These measurements are to be taken at the property line to ensure noise standards are achieved. Given the lack of noise standards in Ashford, we have a case of putting the cart before the horse. Ashford is not prepared, from a regulatory standpoint, to address mega-scale industrial development. It has neither noise regulations nor the expertise to administer them at this point in time. Truck noise, especially diesel engine tractor trailers, creates some of the highest noise levels found in the urban, suburban or rural environment with decibel levels as high as 90 dB(A) (see Appendix 1).

Noise Impacts from Truck Traffic

The estimated truck and vehicular traffic that will be using Route 89 to travel to points to the south and southeast will range from 129 to 167 truck trips a day and 352 to 903 employee trips a day (see previous memo from Attorney Parks). Noise dosimetry calculations conducted on March 31, 2023 at various distances from Interstate 84 determined that tractor trailer traffic can far exceed acceptable noise levels established by the U.S. Department of Housing and Urban Development for residential developments. HUD’s Noise Assessment Guidelines recommend building setbacks of 105 feet from roads when there are 1,500 average daily trips (ADT). Connecticut Department of Transportation traffic count data for 2017 (the pre-Covid era) found a 1,500 ADT on Route 89. The addition of 903 more automobiles and 167 trucks represents a 71% increase in total traffic and an infinite increase in truck traffic – mainly because Route 89 is rarely used as a truck through road.

The added traffic also means acceptable noise levels will not be possible within the front yards of residential lots fronting on Route 89 – a loss of noise free residential property for every Ashford residence on Route 89. More traffic means more noise and more noise means less enjoyment of front and side lawns for many Route 89 homeowners. However, automobile noise is the least of the problems associated with warehouse truck traffic. Based on HUD Noise Assessment Guidelines and the ITE Trip Generation Manual locations along Route 89 will experience much higher noise from the 167 truck trips that will pass south on Route 89 on a daily basis. Because trucks generate noise levels as high as 90 decibels on the A weighted scale (the scale that simulates human hearing), the impacts to residential neighborhoods will be significant. Using HUD assessment procedures, in order to meet an average Day/Night noise level standard of 55 decibels, homeowners would need to be at least 290 feet from Route 89 to experience acceptable outdoor noise levels (see Appendix 2). For the average 3 acre lot in Ashford that would mean 50% of the depth of the lot area would not have acceptable noise levels.1 In effect, truck traffic would force families to keep their activities to the rear of their lot or stay inside.

Noise Attenuation with Distance

Noise dosimetry conducted on March 31, 2023 confirmed what we all generally understand; truck and automobile noise attenuates with distance. The most important point revealed by the data in table 1 is that noise levels at 57 feet from Interstate 84 still far exceeded residential noise standards established by the U.S. Department of Housing and Urban Development (i.e., 74.2 dB(A) at 57 feet versus the 55 dB(A) day/night noise standard established for residences). 

Numerous factors affect the actual noise levels in any given location including vegetative buffers, travel speeds, bad mufflers, diesel engines, speed bumps, traffic signals, road grades, etc. However, all things being equal, since noise levels attenuate in accordance with the inverse square law noise levels identified through the noise dosimetrystudy confirm the same findings achieved through the use of HUD’s nomogram methodology (see Appendix 2).