Noise Levels in Original Daly City, Daly City, CA | Find Quiet Neighborhoods With Our Sound Map
59 dBA
Average noise across Original Daly City
Normal conversation an arm’s length away
7,425
Residents above the EPA 55 dBA threshold
72% of Original Daly City residents
82 dBA
Loudest residential point
Food blender at arm’s length
This map shows modeled outdoor noise across Original Daly City 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 7,425 Original Daly City residents, or 71.9%, live above that level. By land area, 83.0% of Original Daly City is above 55 dBA.
17.0% below 55 dBA
83.0% above 55 dBA
See how noise in Original Daly City compares to similar-sized neighborhoods.
Noise by Part of Original Daly City
Average noise levels for Original Daly City residents, grouped by direction from the center of Original Daly City. The highest population-weighted average is in southern Original Daly City; the lowest is in northeastern Original Daly City, where just 64% of residents live in blocks above the EPA's 55 dBA threshold, three-quarters of the share in the loudest section.
Southern Original Daly City
67.5 dBA · Loud
Highway traffic 50 ft away
Northwestern Original Daly City
65.4 dBA · Loud
Busy restaurant
Central Original Daly City
65.3 dBA · Loud
Busy restaurant
Northern Original Daly City
62.5 dBA · Loud
Busy restaurant
Northeastern Original Daly City
60.9 dBA · Loud
Normal conversation an arm’s length away
To the human ear, noise in southern Original Daly City sounds about 58% louder than in northeastern Original Daly City, a 6.6 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 Junipero Serra Fwy do you need to be?
Junipero Serra Fwy produces an estimated 79 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 quiet suburban street at night.
At source
79 dBA
City bus interior
165 ft
65 dBA
Busy restaurant
330 ft
57 dBA
Normal conversation an arm’s length away
660 ft
49 dBA
Quiet office
¼ mile
41 dBA
Quiet suburban street at night
½ mile
35 dBA
Soft rainfall
Calculated from the model's calibrated attenuation formula. About 2% of Original Daly City sits under tree canopy (much lighter than most neighborhoods) and roughly 61% 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.
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Rail Noise
Active freight rail runs through parts of Original Daly City. For most blocks the rail-only contribution is small. Combined road-plus-rail noise rarely exceeds road noise on its own. The exceptions are the handful of blocks within roughly a quarter mile of the right-of-way during pass-through hours.
Use the Rail toggle on the map above to isolate rail's contribution from road and aviation.
Airport Noise
San Francisco International (SFO) sits southeast of Original Daly City. The U.S. Department of Transportation measures aviation noise around this airport directly, and the model uses those federal measurements rather than synthetic predictions.
Blocks under the approach and departure paths carry combined road-plus-aviation noise, with some exceeding 45 dBA on the map's Overall layer. Blocks on the opposite side of Original Daly City, particularly to the northwest, show no measurable aviation contribution. Use the Aviation toggle on the map above to isolate the airport's footprint.
How Noise Is Distributed Across Original Daly City
The bar chart below shows the share of Original Daly City residents in each noise band. About 17% of residents live below the EPA's 55 dBA threshold, and roughly 27% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.
How Original Daly City Compares
Original Daly City sits at the quieter end of the spectrum. Below: how Original Daly City's average outdoor noise and share of residents above the EPA threshold compare with St. Francis, Serramonte, Outer Mission, and Castro-Upper Market.
Average noise level (dBA)
Original Daly City's 58.6 dBA pop-weighted average is at the quieter end of the spectrum. California as a whole averages 54.0 dBA and the U.S. averages 52.0 dBA. Both are lower than Original Daly City because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 71.9% of Original Daly City residents live in blocks where outdoor levels exceed the EPA's 55 dBA threshold. That's in the middle of its peer group. Measured by land area instead, 83.0% of Original Daly City's footprint sits above 55 dBA, against a California average of 36.0% and a national average of 28.1%.
What This Means if You're Moving to Original Daly City
- Distance from highways matters more than the neighborhood name. Two homes in the same zip code can differ by 20 dBA if one sits 100 meters from Junipero Serra Fwy and the other 500 meters away. The model captures this at 100-meter resolution, so noise exposure changes block by block.
- Tree canopy can help reduce modeled noise exposure. Roughly 2% of Original Daly City is under tree cover (much lighter than most neighborhoods), and the dominant land cover is medium-intensity developed land. Both are measured from federal USDA Forest Service and USGS satellite imagery at 30-meter resolution. Streets with 60% or higher canopy show 3 to 5 dBA lower noise than comparable streets with bare ground or pavement, which is why the per-place decay rate above already accounts for it.
- Airport noise is directional. San Francisco International's approach paths concentrate aviation noise to the southeast. Neighborhoods to the northwest of downtown show no measurable contribution from the airport.
