Noise Levels in Napili-Honokowai, Lahaina, HI | Find Quiet Neighborhoods With Our Sound Map
54 dBA
Average noise across Napili-Honokowai
Quiet office to normal conversation
2,648
Residents above the EPA 55 dBA threshold
34% of Napili-Honokowai residents
67 dBA
Loudest residential point
Highway traffic 50 ft away
This map shows modeled outdoor noise across Napili-Honokowai 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 2,648 Napili-Honokowai residents, or 34.5%, live above that level. By land area, 29.3% of Napili-Honokowai is above 55 dBA.
Average noise levels for Napili-Honokowai residents, grouped by direction from the center of Napili-Honokowai. Southern Napili-Honokowai carries the highest population-weighted average; Eastern Napili-Honokowai carries the lowest. Just 0% of residents in Eastern Napili-Honokowai live in blocks above the EPA's 55 dBA threshold, a fifth of the share in Southern Napili-Honokowai.
Central Napili-Honokowai
51.9 dBA · Moderate
Quiet office to normal conversation
30% of people above 55 dBA
QuietLoud
Eastern Napili-Honokowai
35.4 dBA · Quiet
Soft rainfall
0% of people above 55 dBA
QuietLoud
Northern Napili-Honokowai
55.0 dBA · Moderate-loud
Quiet office to normal conversation
37% of people above 55 dBA
QuietLoud
Southern Napili-Honokowai
55.3 dBA · Moderate-loud
Quiet office to normal conversation
34% of people above 55 dBA
QuietLoud
Western Napili-Honokowai
55.3 dBA · Moderate-loud
Quiet office to normal conversation
42% of people above 55 dBA
QuietLoud
Southern Napili-Honokowai sounds about 297% louder than Eastern Napili-Honokowai to the human ear, a 19.9 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 Honoapiilani Hwy do you need to be?
Honoapiilani Hwy produces an estimated 62 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
62 dBA
Busy restaurant
165 ft
49 dBA
Quiet office
330 ft
41 dBA
Quiet suburban street at night
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 0% of Napili-Honokowai sits under tree canopy (about average for neighborhoods) and roughly 0% 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
Kahului (OGG) sits east of Napili-Honokowai. The U.S. Department of Transportation models aviation noise around this airport from federal traffic data, 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 60 dBA on the map's Overall layer. Blocks on the opposite side of Napili-Honokowai, particularly to the west, show no measurable aviation contribution. Use the Aviation toggle on the map above to isolate the airport's footprint.
How Noise Is Distributed Across Napili-Honokowai
The bar chart below shows the share of Napili-Honokowai residents in each noise band. About 28% 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 Napili-Honokowai Compares
Napili-Honokowai sits the highest among the peer group. Below: how Napili-Honokowai's average outdoor noise and share of residents above the EPA threshold compare with Pukalani, Wailea, kaanapali-lahaina-hi, and waihee-wailuku-hi.
Average noise level (dBA)
Napili-Honokowai's 54.5 dBA pop-weighted average is the highest among the peer group. Hawaii as a whole averages 54.8 dBA and the U.S. averages 52.0 dBA. Both are lower than Napili-Honokowai because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 34.5% of Napili-Honokowai 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, 29.3% of Napili-Honokowai's footprint sits above 55 dBA, against a Hawaii average of 34.4% and a national average of 28.1%.
What This Means if You're Moving to Napili-Honokowai
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 Honoapiilani Hwy 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 0% of Napili-Honokowai is under tree cover (about average for neighborhoods), and the dominant land cover is . 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. Kahului's approach paths concentrate aviation noise to the east. Neighborhoods to the west 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.
