Airport Noise Reduction Hasn’t Stopped the Clamor : Dispute: Burbank Airport officials say statistics show that the noise ‘footprint’ and complaints are both diminishing. Nearby homeowners contend that the real issue is the number of takeoffs and landings, which have doubled since 1978.
In an unfriendly minuet that has been repeated many times in recent years, Burbank Airport has released statistics showing that it is generating less noise, only to have homeowner group leaders scoff at the data and counter that the noise is actually worse.
It’s the same give-and-take that has raged intermittently since 1978, when the cities of Burbank, Glendale and Pasadena bought the aging facility from Lockheed Corp. and promised that the airport would become a good neighbor.
Airport officials, saying they have kept that promise, this month marshaled pages of computer-generated statistics and several noise “footprint” maps to prove their case.
The information had been routinely published by the Burbank-Glendale-Pasadena Airport Authority in quarterly reports to its governing board, but was never before assembled to cover the entire span of the airport’s public ownership, spokesman Victor Gill said.
“What the chart showed remarkably to us, and what we wanted to point out to the commissioners, was just how far they really have come,” Gill said.
“Noise is down, and complaints are down,” said Robert Garcin, president of the nine-member airport commission. “We are in harmony with the neighborhood, except for a handful who continue to complain.”
“Nothing but a big lie,” said Tom Paterson of North Hollywood, chairman of the East Valley Airport Communities Coalition, an anti-noise group formed by nine homeowner groups.
“The airport is close to twice as noisy as it was in 1978,” said Richard Close, president of the Sherman Oaks Homeowners Assn., who has been attacking airport noise since the mid-1970s. “They have broken every promise.”
As before, the latest dispute centers on a little-known method of noise measurement known as the CNEL--the Community Noise Equivalent Level.
Airport officials call the CNEL a valuable tool for measuring the noise burden around the airport, but noise protesters call it a “public relations tool” and “totally irrelevant” to what residents experience under the flight paths.
All airports are mandated by the state Legislature to produce CNEL measurements, which are based on decibel readings of noise. Burbank Airport records noise at 15 listening stations around the airport.
The readings are added together and averaged over a 24-hour period under a formula that gives a greater weight to evening and night noise than to daytime noise on the theory that jet roar at night is a greater nuisance.
Periodically, the daily averages are added and averaged, and the resulting averages are used to draw imaginary lines around the airport on a map. These lines define noise contours, called “footprints.”
The 65 CNEL footprint, for instance, encloses the area in which all the average readings are 65 decibels or higher.
When the authority bought the airport 12 years ago, airports in California were prohibited from generating noise above 70 CNEL in areas containing homes and schools.
In 1986, the standard was tightened to 65 CNEL. Like most airports, Burbank has never met either standard.
But the state’s bite is nothing like its bark; the state Department of Transportation regularly gives airports waivers to continue operating after conducting lengthy hearings to determine if a good-faith effort is being made to meet the noise standard.
And the CNEL maps indicate that the authority is indeed doing something about noise.
Garcin noted that the size of the area containing residences and schools in which 70 CNEL is not met has dropped from 407 acres in 1978 to 22 acres this spring.
And telephoned complaints to the authority have also “dropped dramatically,” Garcin said, from 2,200 calls in 1985 to 318 calls in 1989.
“We are not saying that the airport does not generate noise,” he said. “But things have improved.”
Airport staff members say the shrinking of the noise contour results chiefly from the introduction of quieter Stage Three jets, a process that was completed three years ago.
Burbank was the first airport in the nation to ban aircraft not built or retrofitted to meet Stage Three criteria, the toughest standards now available.
The shrinkage of the 65 CNEL area has been steady but substantially slower than the 70 CNEL area cited by Garcin, according to an authority report.
Close, however, contends that CNEL maps are “totally irrelevant. They make sense only to a computer. The real issue is the number of interruptions.”
Close noted that next month, when USAir is scheduled to add seven flights at the airport, the number of daily flights--each accounting for one landing and one takeoff--interrupting neighborhoods north, south and west of the airport will be double the number in 1978.
In the intervening years, planes have become somewhat quieter as a result of prodding by the Federal Aviation Administration, Close said.
“But the fact that each plane is slightly less noisy is unimportant compared to a doubling of the number of flights,” he said.
“Every commercial jet disturbs residents in a wide section of the Valley.”
In response to the authority’s oft-repeated challenge to suggest a better measure of noise than the CNEL, Close and others say they want to limit the airport to a maximum number of flights each day that generate noise above a yet-to-be-determined level.
As for the drop in telephoned complaints, Close said, “Everyone has finally come to the conclusion that it’s a waste of time to complain.
“The airport authority does not listen to local congressmen, to the L. A. City Council, to state legislators,” he said, listing some of the officials who have battled to lower noise from the airport. “So why would they listen to a resident?”
In rebuttal to what he termed “the authority’s latest public relations barrage about lowering noise,” Paterson has studied the latest noise report and issued a counter-report.
Noise contour maps issued by the authority show that the average noise level at a station near Burbank Boulevard, 1 1/2 miles south of the airport, is less than at a station on Pacific Avenue, one-quarter of a mile south of the runway, Paterson noted.
But Paterson found numerous instances in the authority’s data when the same jet generated a higher decibel level--usually in the 95- to 100-decibel range--at Burbank Boulevard than at Pacific Avenue.
“These instances we have found show that the CNEL method masks rather than illuminates the intensity of a single takeoff,” he said.
Airport officials admit that noise readings will yield such anomalies, but insist that the CNEL is the best method of taking into account the variety of factors affecting noise impact on the ground, including wind and slight variations in flight pattern.
“It’s not perfect, and I know it creates confusion,” Garcin said. “But over the years, I have yet to hear anything suggested that is better.”
“From the airport’s point of view, the CNEL is a wondrous thing,” Close said. “It allows them to simultaneously increase the number of flights while claiming to reduce noise.”
BURBANK AIRPORT’S NOISE ‘FOOTPRINT’ Area (in acres) of excessive airport noise
1978 1986 1990 Residential Residential Residential & Schools Total & Schools Total & Schools Total 65 CNEL* N/A 3,300 437 1,533 294 1,201 70 CNEL 407 1,470 84 680 22 526
* The Community Noise Equivalent Level (CNEL), derived by averaging noise readings, is the state-mandated measure of airport noise. In January, 1986, the state tightened the CNEL standard for acceptable community noise from 70 decibels to 65 decibels. The 65 CNEL zone encloses the area in which all the average readings are 65 decibels or higher.
Source: Burbank-Glendale-Pasadena Airport Authority
