This map shows modeled outdoor noise across Horizon City 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 3,059 Horizon City residents, or 24.6%, live above that level. By land area, 25.1% of Horizon City is above 55 dBA.
See how noise in Horizon City compares to similar-sized cities.
Noise by Part of Horizon City
Average noise levels for Horizon City residents, grouped by direction from the center of Horizon City. The highest population-weighted average is in southwestern Horizon City; the lowest is in northeastern Horizon City, where just 1% of residents live in blocks above the EPA's 55 dBA threshold, a fifth of the share in the loudest section.
Southwestern Horizon City
7% of people above 55 dBA
Southeastern Horizon City
48% of people above 55 dBA
Northwestern Horizon City
19% of people above 55 dBA
Eastern Horizon City
20% of people above 55 dBA
Northeastern Horizon City
1% of people above 55 dBA
To the human ear, noise in southwestern Horizon City sounds about 107% louder than in northeastern Horizon City, a 10.5 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 66 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 0% of Horizon City sits under tree canopy (much lighter than most cities) and roughly 38% 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.