This map shows modeled outdoor noise across 97738 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 617 97738 residents, or 30.6%, live above that level. By land area, 8.7% of 97738 is above 55 dBA.
See how noise in 97738 compares to similar-sized zip codes.
Noise by Part of 97738
Average noise levels for 97738 residents, grouped by direction from the center of 97738. Central 97738 carries the highest population-weighted average; Western 97738 carries the lowest. Just 3% of residents in Western 97738 live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Central 97738.
Central 97738
47% of people above 55 dBA
Eastern 97738
23% of people above 55 dBA
Northern 97738
33% of people above 55 dBA
Southern 97738
16% of people above 55 dBA
Western 97738
3% of people above 55 dBA
Central 97738 sounds about 82% louder than Western 97738 to the human ear, a 8.6 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 20 do you need to be?
US Route 20 produces an estimated 64 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 2% of 97738 sits under tree canopy (much lighter than most zip codes) and roughly 24% 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.