This map shows modeled outdoor noise across Otter Rock 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 Otter Rock residents, or 13.1%, live above that level. By land area, 11.7% of Otter Rock is above 55 dBA.
See how noise in Otter Rock compares to similar-sized cities.
Noise by Part of Otter Rock
Average noise levels for Otter Rock residents, grouped by direction from the center of Otter Rock. Southern Otter Rock carries the highest population-weighted average; Eastern Otter Rock carries the lowest. Just 4% of residents in Eastern Otter Rock live in blocks above the EPA's 55 dBA threshold, a third of the share in Southern Otter Rock.
Central Otter Rock
13% of people above 55 dBA
Eastern Otter Rock
4% of people above 55 dBA
Northern Otter Rock
12% of people above 55 dBA
Southern Otter Rock
16% of people above 55 dBA
Southern Otter Rock sounds about 47% louder than Eastern Otter Rock to the human ear, a 5.6 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 US Route 101 do you need to be?
US Route 101 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 63% of Otter Rock sits under tree canopy (much heavier than most cities) and roughly 12% 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.