Noise Levels in Snohomish Cascade, Silver Firs, WA | Find Quiet Neighborhoods With Our Sound Map
52 dBA
Average noise across Snohomish Cascade
Quiet office to normal conversation
849
Residents above the EPA 55 dBA threshold
20% of Snohomish Cascade residents
68 dBA
Loudest residential point
Highway traffic 50 ft away
This map shows modeled outdoor noise across Snohomish Cascade 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 849 Snohomish Cascade residents, or 20.5%, live above that level. By land area, 20.4% of Snohomish Cascade is above 55 dBA.
Average noise levels for Snohomish Cascade residents, grouped by direction from the center of Snohomish Cascade. Eastern Snohomish Cascade carries the highest population-weighted average; Southern Snohomish Cascade carries the lowest. Just 13% of residents in Southern Snohomish Cascade live in blocks above the EPA's 55 dBA threshold, a third of the share in Eastern Snohomish Cascade.
Central Snohomish Cascade
50.7 dBA · Moderate
Quiet office
15% of people above 55 dBA
QuietLoud
Eastern Snohomish Cascade
55.9 dBA · Moderate-loud
Quiet office to normal conversation
43% of people above 55 dBA
QuietLoud
Northern Snohomish Cascade
52.3 dBA · Moderate
Quiet office to normal conversation
27% of people above 55 dBA
QuietLoud
Southern Snohomish Cascade
50.3 dBA · Moderate
Quiet office
13% of people above 55 dBA
QuietLoud
Eastern Snohomish Cascade sounds about 47% louder than Southern Snohomish Cascade to the human ear, a 5.6 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 134TH Pl SE do you need to be?
134TH Pl SE produces an estimated 65 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
65 dBA
Busy restaurant
165 ft
54 dBA
Quiet office to normal conversation
330 ft
47 dBA
Quiet office
660 ft
40 dBA
Soft rainfall
¼ mile
35 dBA
Soft rainfall
½ mile
35 dBA
Soft rainfall
Calculated from the model's calibrated attenuation formula. About 40% of Snohomish Cascade sits under tree canopy (much heavier than most neighborhoods) and roughly 44% 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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Airport Noise
Seattle-Tacoma International (SEA) sits south of Snohomish Cascade. 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 Snohomish Cascade, particularly to the north, show no measurable aviation contribution. Use the Aviation toggle on the map above to isolate the airport's footprint.
How Noise Is Distributed Across Snohomish Cascade
The bar chart below shows the share of Snohomish Cascade residents in each noise band. About 83% 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 Snohomish Cascade Compares
Snohomish Cascade sits the lowest among the peer group. Below: how Snohomish Cascade's average outdoor noise and share of residents above the EPA threshold compare with Filbert-Winesap, Westhill, Downtown Lynnwood, and Canyon Park.
Average noise level (dBA)
Snohomish Cascade's 51.5 dBA pop-weighted average is the lowest among the peer group. Washington as a whole averages 51.3 dBA and the U.S. averages 52.0 dBA. Both are lower than Snohomish Cascade because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 20.5% of Snohomish Cascade residents live in blocks where outdoor levels exceed the EPA's 55 dBA threshold. That's fewer than any of its peer group. Measured by land area instead, 20.4% of Snohomish Cascade's footprint sits above 55 dBA, against a Washington average of 27.7% and a national average of 28.1%.
What This Means if You're Moving to Snohomish Cascade
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 134TH Pl SE 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 40% of Snohomish Cascade is under tree cover (much heavier than most neighborhoods), and the dominant land cover is medium-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. Seattle-Tacoma International's approach paths concentrate aviation noise to the south. Neighborhoods to the north of downtown show no measurable contribution from the airport.
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.
