Noise Levels in South Westport, MA | Find Quiet Neighborhoods With Our Sound Map

43 dBA
Average noise across South Westport
Quiet suburban street at night
8
Residents above the EPA 55 dBA threshold
2% of South Westport residents
63 dBA
Loudest residential point
Busy restaurant

This map shows modeled outdoor noise across South Westport 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.

Overall
Road
Rail
Aviation
South Westport, MA Map of Noise Levels in South Westport
Click the map to explore
35 45 55 70 90
Quietest (dBA) Loudest
Colorblind friendly off

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 8 South Westport residents, or 2.2%, live above that level. By land area, 1.8% of South Westport is above 55 dBA.

See how noise in South Westport compares to similar-sized cities.

Noise by Part of South Westport

Average noise levels for South Westport residents, grouped by direction from the center of South Westport. Western South Westport carries the highest population-weighted average; Northern South Westport carries the lowest. Just 0% of residents in Northern South Westport live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Western South Westport.

Northern South Westport

39.2 dBA · Quiet
Soft rainfall

0% of people above 55 dBA

QuietLoud

Southern South Westport

42.9 dBA · Quiet
Quiet suburban street at night

2% of people above 55 dBA

QuietLoud

Western South Westport

48.3 dBA · Mostly quiet
Quiet office

8% of people above 55 dBA

QuietLoud

Western South Westport sounds about 88% louder than Northern South Westport to the human ear, a 9.1 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 far back from do you need to be?

produces an estimated 63 dBA at its loudest centerline points. Noise drops logarithmically with distance, with the exact rate depending on what's between you and the road. Tree cover, walls, terrain, and pavement type all matter. At roughly a quarter mile back, traffic fades into the noise level of a soft rainfall.

At source
63 dBA
Busy restaurant
165 ft
49 dBA
Quiet office
330 ft
41 dBA
Soft rainfall
660 ft
35 dBA
Soft rainfall
¼ mile
35 dBA
Soft rainfall
½ mile
35 dBA
Soft rainfall

Calculated from the model's calibrated attenuation formula. About 76% of South Westport sits under tree canopy (much heavier than most cities) and roughly 0% is impervious surface like pavement and rooftops. Both are folded into the per-place decay rate above. Heavier canopy pulls noise down faster with distance; impervious surfaces slow the drop.

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How Noise Is Distributed Across South Westport

The bar chart below shows the share of South Westport residents in each noise band. About 100% of residents live below the EPA's 55 dBA threshold, and roughly 0% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.

How South Westport Compares

South Westport sits at the quieter end of the spectrum. Below: how South Westport's average outdoor noise and share of residents above the EPA threshold compare with Westport Point, Dartmouth, Chartley, and Assonet Bay Shores.

Average noise level (dBA)

South Westport's 42.6 dBA pop-weighted average is at the quieter end of the spectrum. Massachusetts as a whole averages 54.3 dBA and the U.S. averages 52.0 dBA. Both are lower than South Westport because most of either area is rural land away from major roads.

Share of residents above 55 dBA

About 2.2% of South Westport residents live in blocks where outdoor levels exceed the EPA's 55 dBA threshold. That's in the middle of its peer group. Measured by land area instead, 1.8% of South Westport'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 South Westport

  • 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 76% of South Westport is under tree cover (much heavier than most cities), and the dominant land cover is deciduous forest. 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.