Consider two northeast Pierce County cities, where quiet has been the norm but now the sounds of modern life are whirring, pinging and clanging.

In Bonney Lake, the sounds of a new nightclub disturb a residential street. In Sumner, it’s a loud heat pump or an all-night trucking business.

Residents in both cities have complained. The city councils have responded with new noise control ordinances. Bonney Lake passed its version last week, and Sumner is expected to do the same July 28.

They have struggled with the central question: How do you tell the difference between a private irritation and a public nuisance?

Enter the machines.

Both cities are planning to use decibel meters to answer that question and have adopted the state table of maximum permissible sound levels for various environments – residential, commercial and industrial.

In a residential neighborhood, for example, the maximum noise level allowed from another property would be 55 decibels. The maximum noise level allowed from a commercial zone into a neighborhood would be 57 decibels; from an industrial zone, 60 decibels.

The standards are reduced by 10 decibels at night.

Neither city would patrol the streets for noise and would respond only to complaints. Enforcement could range from civil infractions to criminal misdemeanors.

In Bonney Lake, after three convictions in a year, a noise control plan would be prepared.

In explaining the decibel table to the Sumner City Council last week, Paul Rogerson, the city’s director of community development, said the idea is to “create measurable and enforceable standards related to noise.”

So how loud is a decibel? In his memo to the council, Rogerson cited a decibel table of common sounds used by the National Institute on Deafness and Other Communication Disorders.

Bonney Lake City Attorney Jim Dionne, however, isn’t so sure the decibel meters are the answer for his city up on the plateau. He opposed their use, arguing unsuccessfully that machines can make enforcement more difficult by setting a noise standard that, even if met, still may not satisfy nearby property owners.

In their noise ordinances, both cities have kept their old standard of a public nuisance noise based on a subjective standard of whether it disturbs the peace of residents.

Dionne said the subjective standard should be sufficient to go after noise scofflaws. Using established decibel levels – and machines to measure them – makes it difficult for a city to go after a nuisance noise if it registers below the decibel standards, he said.

Machines have taken over enforcement of drunken driving laws, he said, and launched an industry of pseudo experts on Breathalyzers. The same could happen with noise control, he said.

Bonney Lake police, however, successfully urged the City Council to adopt a standard instead of leaving officers to determine what is objectionable and what is not. The result has been that officers find themselves caught in the middle.

Most larger cities in the state use decibel levels, usually because they can afford the cost of buying and certifying the meters and training operators, according to the Washington Municipal Research Services Center.

Some Pierce County cities and towns, such as Lakewood and Puyallup, have chosen the “public disturbance” approach.

This spring, Tacoma’s first comprehensive noise ordinance went into effect, largely motivated by complaints from residents who live near the thriving Sixth Avenue restaurant and nightclub corridor.

Tacoma’s ordinance is based on decibels, but instead of adopting the state standards, the city adopted its own permissible sound levels.

Sumner Mayor Dave Enslow said he thinks objective noise standards are needed because they provide guidelines for business owners to meet.

The Sumner City Council tabled a vote on its noise ordinance last week for more discussion. At the meeting, Ben DeGoede, general manager of the Windmill Gardens event center, showed up with his own decibel meter.

Though he thought the decibel levels were lower than needed, he said he wasn’t opposed to a noise control ordinance and was working to reduce the sound from Windmill Gardens events.

Enslow said he took DeGoede’s efforts as a sign that the city’s proposed standards were already doing their job.

Mike Archbold: 253-597-8692

DECIBEL Levels of common sounds

10: Normal breathing

50-65: Normal conversation

Under 60: Comfortable hearing level80: Alarm clock

100: Chain saw

140: Jet engine