This map shows modeled outdoor noise across Gillespie County 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 1,899 Gillespie County residents, or 9.2%, live above that level. By land area, 10.6% of Gillespie County is above 55 dBA.
See how noise in Gillespie County compares to similar-sized counties.
Noise by Part of Gillespie County
Average noise levels for Gillespie County residents, grouped by direction from the center of Gillespie County. The highest population-weighted average is in the Fredericksburg area (eastern Gillespie County); the lowest is in northern Gillespie County, where just 0% of residents live in blocks above the EPA's 55 dBA threshold, a fifth of the share in the loudest section.
Fredericksburg
9% of people above 55 dBA
Southwestern Gillespie County
1% of people above 55 dBA
Southeastern Gillespie County
2% of people above 55 dBA
Western Gillespie County
0% of people above 55 dBA
Northern Gillespie County
0% of people above 55 dBA
To the human ear, noise in the Fredericksburg area (eastern Gillespie County) sounds about 68% louder than in northern Gillespie County, a 7.5 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 I-10 do you need to be?
I-10 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 6% of Gillespie County sits under tree canopy (lighter than most counties) and roughly 14% 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.