This map shows modeled outdoor noise across Hemlock 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 45 Hemlock residents, or 2.9%, live above that level. By land area, 5.6% of Hemlock is above 55 dBA.
See how noise in Hemlock compares to similar-sized cities.
Noise by Part of Hemlock
Average noise levels for Hemlock residents, grouped by direction from the center of Hemlock. Northern Hemlock carries the highest population-weighted average; Southern Hemlock carries the lowest. Just 3% of residents in Southern Hemlock live in blocks above the EPA's 55 dBA threshold, roughly the same as the share in Northern Hemlock.
Eastern Hemlock
4% of people above 55 dBA
Northern Hemlock
3% of people above 55 dBA
Southern Hemlock
3% of people above 55 dBA
Western Hemlock
2% of people above 55 dBA
Northern Hemlock sounds about 41% louder than Southern Hemlock to the human ear, a 5.0 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 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.
Calculated from the model's calibrated attenuation formula. About 36% of Hemlock sits under tree canopy (about average for 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.