Noise Levels in Western Hills, San Mateo, CA | Find Quiet Neighborhoods With Our Sound Map

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 1,552 Western Hills residents, or 51.8%, live above that level. By land area, 53.3% of Western Hills is above 55 dBA.

See how noise in Western Hills compares to similar-sized neighborhoods.

Noise by Part of Western Hills

Average noise levels for Western Hills residents, grouped by direction from the center of Western Hills. The highest population-weighted average is in southwestern Western Hills; the lowest is in northern Western Hills, where just 13% of residents live in blocks above the EPA's 55 dBA threshold, a third of the share in the loudest section.

To the human ear, noise in southwestern Western Hills sounds about 246% louder than in northern Western Hills, a 17.9 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.

Airport Noise

San Francisco International (SFO) sits north of Western Hills. 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 75 dBA on the map's Overall layer. Blocks on the opposite side of Western Hills, particularly to the south, show no measurable aviation contribution. Use the Aviation toggle on the map above to isolate the airport's footprint.

How Noise Is Distributed Across Western Hills

The bar chart below shows the share of Western Hills residents in each noise band. About 40% of residents live below the EPA's 55 dBA threshold, and roughly 37% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.

How Western Hills Compares

Western Hills sits the highest among the peer group. Below: how Western Hills's average outdoor noise and share of residents above the EPA threshold compare with Downtown Burlingame, Mills Estates, West Atherton, and Redwood Village.

Average noise level (dBA)

Western Hills's 56.4 dBA pop-weighted average is the highest among the peer group. California as a whole averages 54.0 dBA and the U.S. averages 52.0 dBA. Both are lower than Western Hills because most of either area is rural land away from major roads.

Share of residents above 55 dBA

About 51.8% of Western Hills 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, 53.3% of Western Hills'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 Western Hills

• 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 J Arthur Younger 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 14% of Western Hills is under tree cover (about average for neighborhoods), and the dominant land cover is low-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 north. Neighborhoods to the south of downtown show no measurable contribution from the airport.

Sources & Methodology