This map shows modeled outdoor noise across Healdsburg 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 2,719 Healdsburg residents, or 20.6%, live above that level. By land area, 24.7% of Healdsburg is above 55 dBA.
See how noise in Healdsburg compares to similar-sized cities.
Noise by Part of Healdsburg
Average noise levels for Healdsburg residents, grouped by direction from the center of Healdsburg. The highest population-weighted average is in western Healdsburg; the lowest is in eastern Healdsburg, where just 2% of residents live in blocks above the EPA's 55 dBA threshold, a fifth of the share in the loudest section.
Western Healdsburg
30% of people above 55 dBA
Southern Healdsburg
32% of people above 55 dBA
Central Healdsburg
26% of people above 55 dBA
Northeastern Healdsburg
11% of people above 55 dBA
Eastern Healdsburg
2% of people above 55 dBA
To the human ear, noise in western Healdsburg sounds about 214% louder than in eastern Healdsburg, a 16.5 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 US Hwy 101 do you need to be?
US Hwy 101 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 12% of Healdsburg sits under tree canopy (lighter than most cities) and roughly 38% 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.