Quiet LA

Noise in Greater Valley Glen

Modeled estimates for general information only — not measurements, not a guarantee, and not for legal, medical or real-estate decisions.

Across 69,896 modeled building-façade points in the Greater Valley Glen Neighborhood Council area, the median 24-hour level is 54.0 dB CNEL; one point in ten is below 46.2 dB and one in ten above 67.3 dB. At night (10 pm–7 am) the median is 46.0 dB.

The Greater Valley Glen Neighborhood Council area is one of the City of Los Angeles’ certified Neighborhood Council areas. Its figures use the boundary from the City’s Neighborhood Councils (Certified) map layer.

See Greater Valley Glen on the map

Figures from the map data release of . The live map may show a different release.

Greater Valley Glen and the Los Angeles County reference

Modeled levels at building-façade points: Greater Valley Glen alongside the Los Angeles County reference. The 24-hour CNEL includes aircraft; the Night level does not.
Greater Valley GlenLA County (reference)
24-hour level (CNEL)
Median54.0 dB56.1 dB
1 point in 10 is below46.2 dB45.8 dB
1 point in 10 is above67.3 dB68.0 dB
Points at or above 55 dB45.9%54.8%
Points at or above 60 dB27.0%34.1%
Points at or above 65 dB14.2%17.3%
Night (10 pm–7 am, LAeq)
Median46.0 dB47.5 dB
1 point in 10 is below38.2 dB37.5 dB
1 point in 10 is above59.2 dB59.8 dB
Points at or above 45 dB55.8%62.0%
Points at or above 50 dB34.0%39.6%
Points at or above 55 dB18.6%22.1%

What the model shows as the main source

At 100.0% of the building-façade points in the Greater Valley Glen Neighborhood Council area, road traffic is the largest modeled contribution to the 24-hour level; rail is the largest at under 0.1% and aircraft at under 0.1%.

The rail figures come from the rail layer. Only the San Fernando Valley main lines are modeled (Metrolink’s Ventura County and Antelope Valley lines, Amtrak and Union Pacific freight, with horns at public crossings); light rail, Metro Rail, other Metrolink lines and rail yards are not. Here, the modeled train level alone is 40 dB CNEL or more at 5.2% of the points.

Under 0.1% of the points here lie inside the estimated 55 dB CNEL airport line, the edge of the airport-contour estimate; aircraft below that line are not in the figures.

Helicopters are not mapped. Sirens are an optional map layer (an estimate of LAFD fire and ambulance responses, City of LA only), off by default and not in these figures.

More on each source: freeway and road noise, train and rail noise and LAX and aircraft noise.

Buildings

The model has walls for 13,124 buildings in the Greater Valley Glen Neighborhood Council area. For 37.9% of them the loudest wall is at or above 60 dB CNEL, and for 22.2% at or above 65 dB CNEL. For at least 21.5%, the less-exposed side is 10 dB or more below the loudest wall.

Which side of a building a bedroom or window faces changes the modeled level there: on the decibel scale, a difference of about 10 dB is heard as twice or half as loud. On the map, selecting a building shows its loudest and its least-exposed wall.

About these figures

The points are building façades of all types, 4 m up and 2 m out from the walls of every kind of building, not only homes. Long walls and large buildings have more points, so the figures describe buildings, not people or households.

The model is uncalibrated. At a single spot it is typically about 6 dB off, higher or lower, and compared with measurements it reads about 3.6 to 4.4 dB high on average at measured sites where freeway noise dominates, with a wide spread. An area figure says nothing certain about any one building; look up an address on the map for its own modeled levels.

Partly modeled areas are described by their modeled part only. The figures come from building façades only, so open land does not affect them. On the map, land with no freeway or major road within 3 km has no computed value and shows the lowest color; that is an assumption, not a measurement.

Figures are road, rail and aircraft at building façades; the map’s background “city hum” layer is not included in these figures.

Not in the figures: helicopters (not mapped), sirens (an optional map layer, off by default), construction, events, nightlife, neighbors and sound indoors.

Neighborhood Council areas cover only part of the City of Los Angeles and overlap in places; a point in an overlap counts for each council, so council figures cannot be added up.

Neighborhood Council boundaries: City of Los Angeles, Bureau of Engineering (LA GeoHub, Neighborhood Councils (Certified)), CC BY 4.0.