This map shows modeled outdoor noise across Bellarthur 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 39 Bellarthur residents, or 7.2%, live above that level. By land area, 14.7% of Bellarthur is above 55 dBA.
See how noise in Bellarthur compares to similar-sized cities.
Noise by Part of Bellarthur
Average noise levels for Bellarthur residents, grouped by direction from the center of Bellarthur. Western Bellarthur carries the highest population-weighted average; Eastern Bellarthur carries the lowest. Just 3% of residents in Eastern Bellarthur live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Western Bellarthur.
Central Bellarthur
7% of people above 55 dBA
Eastern Bellarthur
3% of people above 55 dBA
Northern Bellarthur
15% of people above 55 dBA
Southern Bellarthur
4% of people above 55 dBA
Western Bellarthur
37% of people above 55 dBA
Western Bellarthur sounds about 359% louder than Eastern Bellarthur to the human ear, a 22.0 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 SR-1217 do you need to be?
SR-1217 produces an estimated 55 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.
Calculated from the model's calibrated attenuation formula. About 16% of Bellarthur sits under tree canopy (lighter than most cities) and roughly 4% 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.