This map shows modeled outdoor noise across Westwood-San Francisco 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 2,764 Westwood-San Francisco residents, or 41.3%, live above that level. By land area, 33.8% of Westwood-San Francisco is above 55 dBA.
See how noise in Westwood-San Francisco compares to similar-sized neighborhoods.
Noise by Part of Westwood-San Francisco
Average noise levels for Westwood-San Francisco residents, grouped by direction from the center of Westwood-San Francisco. Eastern Westwood-San Francisco carries the highest population-weighted average; Western Westwood-San Francisco carries the lowest. Just 3% of residents in Western Westwood-San Francisco live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Eastern Westwood-San Francisco.
Central Westwood-San Francisco
44% of people above 55 dBA
Eastern Westwood-San Francisco
93% of people above 55 dBA
Northern Westwood-San Francisco
51% of people above 55 dBA
Southern Westwood-San Francisco
22% of people above 55 dBA
Western Westwood-San Francisco
3% of people above 55 dBA
Eastern Westwood-San Francisco sounds about 466% louder than Western Westwood-San Francisco to the human ear, a 25.0 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 Hwy 29 do you need to be?
State Hwy 29 produces an estimated 76 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 13% of Westwood-San Francisco sits under tree canopy (about average for neighborhoods) and roughly 48% 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.