Noise Levels in Discovery Bay, CA | Find Quiet Neighborhoods With Our Sound Map
49 dBA
Average noise across Discovery Bay
Quiet office
2,407
Residents above the EPA 55 dBA threshold
22% of Discovery Bay residents
88 dBA
Loudest residential point
Lawnmower at 1 m
This map shows modeled outdoor noise across Discovery Bay 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 2,407 Discovery Bay residents, or 21.9%, live above that level. By land area, 15.0% of Discovery Bay is above 55 dBA.
85.0% below 55 dBA
15.0% above 55 dBA
See how noise in Discovery Bay compares to similar-sized cities.
Noise by Part of Discovery Bay
Average noise levels for Discovery Bay residents, grouped by direction from the center of Discovery Bay. The highest population-weighted average is in northern Discovery Bay; the lowest is in eastern Discovery Bay, where just 4% of residents live in blocks above the EPA's 55 dBA threshold, roughly the same as the share in the loudest section.
Northern Discovery Bay
62.0 dBA · Loud
Busy restaurant
Southwestern Discovery Bay
54.7 dBA · Moderate-loud
Quiet office to normal conversation
Western Discovery Bay
51.3 dBA · Moderate
Quiet office to normal conversation
Southeastern Discovery Bay
47.3 dBA · Mostly quiet
Quiet office
Eastern Discovery Bay
46.4 dBA · Mostly quiet
Quiet office
To the human ear, noise in northern Discovery Bay sounds about 195% louder than in eastern Discovery Bay, a 15.6 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 do you need to be?
produces an estimated 88 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 office.
At source
88 dBA
Lawnmower at 1 m
165 ft
73 dBA
City bus interior
330 ft
65 dBA
Busy restaurant
660 ft
56 dBA
Normal conversation an arm’s length away
¼ mile
48 dBA
Quiet office
½ mile
39 dBA
Soft rainfall
Calculated from the model's calibrated attenuation formula. About 2% of Discovery Bay sits under tree canopy (much lighter than most cities) 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.
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Rail Noise
Active freight rail runs through parts of Discovery Bay. 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.
How Noise Is Distributed Across Discovery Bay
The bar chart below shows the share of Discovery Bay residents in each noise band. About 80% of residents live below the EPA's 55 dBA threshold, and roughly 5% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.
How Discovery Bay Compares
Discovery Bay sits the lowest among the peer group. Below: how Discovery Bay's average outdoor noise and share of residents above the EPA threshold compare with Country Club, Banta, Garden Acres, and Clayton.
Average noise level (dBA)
Discovery Bay's 48.7 dBA pop-weighted average is the lowest among the peer group. California as a whole averages 54.0 dBA and the U.S. averages 52.0 dBA. Both are lower than Discovery Bay because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 21.9% of Discovery Bay 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, 15.0% of Discovery Bay'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 Discovery Bay
- 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 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 Discovery Bay is under tree cover (much lighter than most cities), 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.
