This map shows modeled outdoor noise across Greater South 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.
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 5,235 Greater South Side residents, or 62.3%, live above that level. By land area, 69.2% of Greater South Side is above 55 dBA.
See how noise in Greater South Side compares to similar-sized neighborhoods.
Noise by Part of Greater South Side
Average noise levels for Greater South Side residents, grouped by direction from the center of Greater South Side. Western Greater South Side carries the highest population-weighted average; Central Greater South Side carries the lowest. Just 44% of residents in Central Greater South Side live in blocks above the EPA's 55 dBA threshold, roughly the same as the share in Western Greater South Side.
Central Greater South Side
44% of people above 55 dBA
Eastern Greater South Side
65% of people above 55 dBA
Northern Greater South Side
68% of people above 55 dBA
Southern Greater South Side
68% of people above 55 dBA
Western Greater South Side
35% of people above 55 dBA
Western Greater South Side sounds about 80% louder than Central Greater South Side to the human ear, a 8.5 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.
Loudest Road Corridors
The model evaluates every road in Greater South Side 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.
How far back from Fleur Drive, N do you need to be?
Fleur Drive, N produces an estimated 71 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 29% of Greater South Side sits under tree canopy (heavier than most neighborhoods) 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.
Airport Noise
Des Moines International (DSM) sits southwest of Greater South Side. 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 55 dBA on the map's Overall layer. Blocks on the opposite side of Greater South Side, particularly to the northeast, show no measurable aviation contribution. Use the Aviation toggle on the map above to isolate the airport's footprint.
How Noise Is Distributed Across Greater South Side
The bar chart below shows the share of Greater South Side residents in each noise band. About 22% of residents live below the EPA's 55 dBA threshold, and roughly 30% live in blocks above 60 dBA. Long-term exposure in that range is linked to elevated stress hormones and cardiovascular risk.
How Greater South Side Compares
Greater South Side sits at the louder end of the spectrum. Below: how Greater South Side's average outdoor noise and share of residents above the EPA threshold compare with Bloomfield-Allen, Beaverdale, Highland Park, and Drake.
Average noise level (dBA)
Greater South Side's 58.4 dBA pop-weighted average is at the louder end of the spectrum. Iowa as a whole averages 52.2 dBA and the U.S. averages 52.0 dBA. Both are lower than Greater South Side because most of either area is rural land away from major roads.
Share of residents above 55 dBA
About 62.3% of Greater South Side 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, 69.2% of Greater South Side's footprint sits above 55 dBA, against a Iowa average of 23.6% and a national average of 28.1%.
What This Means if You're Moving to Greater South 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 Fleur Drive, N 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 29% of Greater South Side is under tree cover (heavier than most neighborhoods), 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.
- Airport noise is directional. Des Moines International's approach paths concentrate aviation noise to the southwest. Neighborhoods to the northeast 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.
Federal datasets used:
FHWA Highway Performance Monitoring System: road geometry, traffic counts, lane configuration
U.S. DoT Bureau of Transportation Statistics National Transportation Noise Map: aviation and rail noise, road calibration ground truth
USGS / MRLC National Land Cover Database: land cover and impervious surface coverage
USDA Forest Service Tree Canopy Cover: vegetation density for sound propagation
U.S. Census Bureau TIGER/Line: block-level geography and population
U.S. EPA Levels Document: 55 dBA outdoor reference level
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.