This map shows modeled outdoor noise across Main Middle at 100-meter resolution, combining road, aviation, and rail sources. Green areas measure below 45 dBA. Orange and red exceed the EPA's 55 dBA outdoor threshold linked to long-term health effects. Use the layer toggles to view each source on its own or all together.
What the numbers sound like
- 30 dBAWhisper
- 40 dBASoft rainfall
- 45 dBAQuiet suburban street at night
- 50 dBAQuiet office
- 55 dBAEPA outdoor threshold: light traffic 100 ft away
- 60 dBANormal conversation an arm's length away
- 65 dBABusy restaurant
- 70 dBAHighway traffic 50 ft away
- 80 dBACity bus interior
Population Above the EPA Outdoor Threshold
The EPA's 55 dBA outdoor reference level is a common benchmark for residential noise exposure, especially for activity interference, annoyance, and long-term community noise concerns. About 5,385 Main Middle residents, or 62.8%, live above that level. By land area, 64.5% of Main Middle is above 55 dBA.
See how noise in Main Middle compares to similar-sized neighborhoods.
Noise by Part of Main Middle
Average noise levels for Main Middle residents, grouped by direction from the center of Main Middle. The highest population-weighted average is in eastern Main Middle; the lowest is in southwestern Main Middle, where just 59% of residents live in blocks above the EPA's 55 dBA threshold, three-quarters of the share in the loudest section.
Eastern Main Middle
88% of people above 55 dBA
Western Main Middle
67% of people above 55 dBA
Central Main Middle
61% of people above 55 dBA
Northeastern Main Middle
69% of people above 55 dBA
Southwestern Main Middle
59% of people above 55 dBA
To the human ear, noise in eastern Main Middle sounds about 33% louder than in southwestern Main Middle, a 4.1 dBA gap. Every 10 dBA roughly doubles perceived loudness. Within any of these directions, two homes a quarter mile apart can still differ by 10 or more dBA depending on how close they sit to a major highway.
How Noise Is Distributed Across Main Middle
The bar chart below shows the share of Main Middle residents in each noise band. About 37% of residents live below the EPA's 55 dBA threshold, and roughly 14% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.
How Main Middle Compares
Main Middle sits the highest among the peer group. Below: how Main Middle's average outdoor noise and share of residents above the EPA threshold compare with Tatnuck, Broadmeadow Brook, Forest Grove, and University Park.
Average noise level (dBA)
Main Middle's 56.6 dBA pop-weighted average is the highest among the peer group. Massachusetts as a whole averages 54.3 dBA and the U.S. averages 52.0 dBA. Both are lower than Main Middle because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 62.8% of Main Middle residents live in blocks where outdoor levels exceed the EPA's 55 dBA threshold. That's more than any of its peer group. Measured by land area instead, 64.5% of Main Middle's footprint sits above 55 dBA, against a Massachusetts average of 40.0% and a national average of 28.1%.
What This Means if You're Moving to Main Middle
- Distance from highways matters more than the neighborhood name. Two homes in the same zip code can differ by 20 dBA if one sits 100 meters from and the other 500 meters away. The model captures this at 100-meter resolution, so noise exposure changes block by block.
- Tree canopy can help reduce modeled noise exposure. Roughly 20% of Main Middle is under tree cover (heavier than most neighborhoods), and the dominant land cover is medium-intensity developed land. Both are measured from federal USDA Forest Service and USGS satellite imagery at 30-meter resolution. Streets with 60% or higher canopy show 3 to 5 dBA lower noise than comparable streets with bare ground or pavement, which is why the per-place decay rate above already accounts for it.
Sources & Methodology
The BestNeighborhood noise model is calibrated against nearly one million federal ground-truth measurements across four states. Road noise is computed from segment-level federal traffic data and propagated outward using physics-based acoustic decay, with attenuation rates that depend on the surrounding land cover.
Federal datasets used:
FHWA Highway Performance Monitoring System: road geometry, traffic counts, lane configuration
U.S. DoT Bureau of Transportation Statistics National Transportation Noise Map: aviation and rail noise, road calibration ground truth
USGS / MRLC National Land Cover Database: land cover and impervious surface coverage
USDA Forest Service Tree Canopy Cover: vegetation density for sound propagation
U.S. Census Bureau TIGER/Line: block-level geography and population
U.S. EPA Levels Document: 55 dBA outdoor reference level
All inputs are published federal datasets. Block-level noise is computed by combining road, rail, and aviation sound sources in the energy domain, the same physics used in professional environmental noise assessments. Read the full methodology.