Noise Levels in St. Johns, AZ | 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 669 St. Johns residents, or 18.0%, live above that level. By land area, 9.3% of St. Johns is above 55 dBA.

See how noise in St. Johns compares to similar-sized cities.

Noise by Part of St. Johns

Average noise levels for St. Johns residents, grouped by direction from the center of St. Johns. Central St. Johns carries the highest population-weighted average; Southern St. Johns carries the lowest. Just 5% of residents in Southern St. Johns live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Central St. Johns.

Central St. Johns sounds about 111% louder than Southern St. Johns to the human ear, a 10.8 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.

Loudest Road Corridors

The model evaluates every road in St. Johns using federal traffic counts, posted speeds, heavy-truck ratios, and pavement type. The source level shown is the modeled noise at the road centerline, where it is loudest. Noise drops with distance, faster in vegetated areas and slower over open pavement.

Rail Noise

Active freight rail runs through parts of St. Johns. 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 St. Johns

The bar chart below shows the share of St. Johns residents in each noise band. About 87% of residents live below the EPA's 55 dBA threshold, and roughly 0% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.

How St. Johns Compares

St. Johns sits at the quieter end of the spectrum. Below: how St. Johns's average outdoor noise and share of residents above the EPA threshold compare with Eagar, Concho, Pinetop-Lakeside, and Taylor.

Average noise level (dBA)

St. Johns's 49.4 dBA pop-weighted average is at the quieter end of the spectrum. Arizona as a whole averages 53.0 dBA and the U.S. averages 52.0 dBA. Both are lower than St. Johns because most of either area is rural land away from major roads.

Share of residents above 55 dBA

About 18.0% of St. Johns 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, 9.3% of St. Johns's footprint sits above 55 dBA, against a Arizona average of 28.3% and a national average of 28.1%.

What This Means if You're Moving to St. Johns

• 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 ~~s~061~~~~~~~~~~~~~~~~~~~~~~~~~ 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 St. Johns is under tree cover (much lighter than most cities), 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.

Sources & Methodology