This map shows modeled outdoor noise across Grimsley 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 52 Grimsley residents, or 3.1%, live above that level. By land area, 6.7% of Grimsley is above 55 dBA.
See how noise in Grimsley compares to similar-sized cities.
Noise by Part of Grimsley
Average noise levels for Grimsley residents, grouped by direction from the center of Grimsley. Eastern Grimsley carries the highest population-weighted average; Southern Grimsley carries the lowest. Just 1% of residents in Southern Grimsley live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Eastern Grimsley.
Central Grimsley
1% of people above 55 dBA
Eastern Grimsley
8% of people above 55 dBA
Northern Grimsley
2% of people above 55 dBA
Southern Grimsley
1% of people above 55 dBA
Western Grimsley
2% of people above 55 dBA
Eastern Grimsley sounds about 59% louder than Southern Grimsley to the human ear, a 6.7 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 A254 do you need to be?
A254 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 40% of Grimsley 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.