This map shows modeled outdoor noise across Irwin 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 28 Irwin residents, or 7.6%, live above that level. By land area, 9.3% of Irwin is above 55 dBA.
See how noise in Irwin compares to similar-sized cities.
Noise by Part of Irwin
Average noise levels for Irwin residents, grouped by direction from the center of Irwin. Central Irwin carries the highest population-weighted average; Western Irwin carries the lowest. Just 5% of residents in Western Irwin live in blocks above the EPA's 55 dBA threshold, about two-thirds of the share in Central Irwin.
Central Irwin
9% of people above 55 dBA
Eastern Irwin
22% of people above 55 dBA
Northern Irwin
7% of people above 55 dBA
Southern Irwin
6% of people above 55 dBA
Western Irwin
5% of people above 55 dBA
Central Irwin sounds about 30% louder than Western Irwin to the human ear, a 3.8 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 Mccoy Creek do you need to be?
Mccoy Creek produces an estimated 53 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 7% of Irwin 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.