This map shows modeled outdoor noise across San Andreas 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 4,649 San Andreas residents, or 64.1%, live above that level. By land area, 59.1% of San Andreas is above 55 dBA.
See how noise in San Andreas compares to similar-sized neighborhoods.
Noise by Part of San Andreas
Average noise levels for San Andreas residents, grouped by direction from the center of San Andreas. Western San Andreas carries the highest population-weighted average; Southern San Andreas carries the lowest. Just 55% of residents in Southern San Andreas live in blocks above the EPA's 55 dBA threshold, roughly the same as the share in Western San Andreas.
Central San Andreas
52% of people above 55 dBA
Eastern San Andreas
96% of people above 55 dBA
Northern San Andreas
66% of people above 55 dBA
Southern San Andreas
55% of people above 55 dBA
Western San Andreas
64% of people above 55 dBA
Western San Andreas sounds about 107% louder than Southern San Andreas to the human ear, a 10.5 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 State Rte 210 do you need to be?
State Rte 210 produces an estimated 75 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 5% of San Andreas sits under tree canopy (lighter than most neighborhoods) and roughly 50% 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.