Noise Levels in Helena West Side, MT | Find Quiet Neighborhoods With Our Sound Map
54 dBA
Average noise across Helena West Side
Quiet office to normal conversation
1,018
Residents above the EPA 55 dBA threshold
45% of Helena West Side residents
69 dBA
Loudest residential point
Highway traffic 50 ft away
This map shows modeled outdoor noise across Helena West Side 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.
Overall
Road
Rail
Aviation
Click the map to explore
35 dBa55 dBa (EPA limit)90+ dBa
3545557090
Quietest (dBA)Loudest
Colorblind friendlyoff
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 1,018 Helena West Side residents, or 45.2%, live above that level. By land area, 44.4% of Helena West Side is above 55 dBA.
Average noise levels for Helena West Side residents, grouped by direction from the center of Helena West Side. Eastern Helena West Side carries the highest population-weighted average; Southern Helena West Side carries the lowest. Just 20% of residents in Southern Helena West Side live in blocks above the EPA's 55 dBA threshold, a third of the share in Eastern Helena West Side.
Central Helena West Side
55.6 dBA · Moderate-loud
Quiet office to normal conversation
54% of people above 55 dBA
QuietLoud
Eastern Helena West Side
58.1 dBA · Loud
Normal conversation an arm’s length away
84% of people above 55 dBA
QuietLoud
Northern Helena West Side
54.5 dBA · Moderate-loud
Quiet office to normal conversation
33% of people above 55 dBA
QuietLoud
Southern Helena West Side
48.1 dBA · Mostly quiet
Quiet office
20% of people above 55 dBA
QuietLoud
Western Helena West Side
51.0 dBA · Moderate
Quiet office
15% of people above 55 dBA
QuietLoud
Eastern Helena West Side sounds about 100% louder than Southern Helena West Side to the human ear, a 10.0 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 Le Grande Cannon Blvd do you need to be?
Le Grande Cannon Blvd produces an estimated 56 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.
At source
56 dBA
Quiet office to normal conversation
165 ft
43 dBA
Quiet suburban street at night
330 ft
35 dBA
Soft rainfall
660 ft
35 dBA
Soft rainfall
¼ mile
35 dBA
Soft rainfall
½ mile
35 dBA
Soft rainfall
Calculated from the model's calibrated attenuation formula. About 10% of Helena West Side sits under tree canopy (lighter than most cities) and roughly 30% 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 Helena West Side. 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 Helena West Side
The bar chart below shows the share of Helena West Side residents in each noise band. About 54% of residents live below the EPA's 55 dBA threshold, and roughly 4% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.
How Helena West Side Compares
Helena West Side sits the highest among the peer group. Below: how Helena West Side's average outdoor noise and share of residents above the EPA threshold compare with Clancy, Montana City, Helena Valley Northeast, and Fort Harrison.
Average noise level (dBA)
Helena West Side's 53.8 dBA pop-weighted average is the highest among the peer group. Montana as a whole averages 49.0 dBA and the U.S. averages 52.0 dBA. Both are lower than Helena West Side because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 45.2% of Helena West Side residents live in blocks where outdoor levels exceed the EPA's 55 dBA threshold. That's more than any of its peer group. Measured by land area instead, 44.4% of Helena West Side's footprint sits above 55 dBA, against a Montana average of 16.9% and a national average of 28.1%.
What This Means if You're Moving to Helena West Side
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 Le Grande Cannon Blvd 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 10% of Helena West Side is under tree cover (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
The BestNeighborhood noise model is calibrated against nearly one million federal ground-truth measurements across four states. Road noise is computed from segment-level federal traffic data and propagated outward using physics-based acoustic decay, with attenuation rates that depend on the surrounding land cover.
All inputs are published federal datasets. Block-level noise is computed by combining road, rail, and aviation sound sources in the energy domain, the same physics used in professional environmental noise assessments. Read the full methodology.
