The lead contractor on the Interstate 70 expansion project through northeast Denver will press its case Thursday to raise noise limits for extensive overnight work — and to lift them altogether at some points.

But before deciding on the request, which would run for more than four years, a city public health board will hear impassioned pleas about the effects of planned bridge demolitions and other nighttime work on hundreds of households within earshot.

Some already have asked in written comments to the city for an outright denial of Kiewit Infrastructure Co.’s request for a noise variance. Others want Denver to clamp on more restrictions and accommodations for affected neighbors.

“Our community is already being forced to be exposed to noise pollution all day, we should at least get a break at night,” wrote Vanessa Keitzer, who lives less than two blocks from the freeway on St. Paul Street. “The noise variance would lead to sleep disturbances and sleep deprivation. The neighborhoods closest to the I-70 expansion already experience a disproportionate number of health issues.”

This week, a consortium of groups that includes the Elyria and Swansea Neighborhood Association urged the city to require more extensive sound barriers and continual noise monitoring while allowing shorter durations for any major work that exceeds noise limits. Represented by Earthjustice, an environmental law firm, the groups suggested granting a renewable, one-year term for the noise variance, as a way to hold the contractor’s feet to the fire.

Kiewit is part of the Central 70 contracting team of Kiewit-Meridiam Partners, and its noise request is standard on such a huge project. But it’s been 17 years since Denver last considered one of this scope.

Back then, the same main contractor, Kiewit, weathered a fight with neighboring communities to win a noise variance for the Interstate 25 overhaul through southeast Denver and the suburbs.

This week, City Councilman Albus Brooks and others on a new advisory committee got an initial dose of the sounds that could rock them awake. Outside Swansea Elementary, where Kiewit already has erected a sound wall, equipment operators moved large rocks Tuesday night, Brooks said.

When the group stood behind the sound wall, it dampened the noise, he said. But plenty made it through — bringing home for Brooks, who also lives near I-70, that “it’s a major impact for four years. … Imagine an alarm clock going off all night long,” he added.

That’s about what 80 decibels sounds like, and it’s within the range that both Kiewit and the city’s Department of Public Health and Environment have endorsed for a heightened overnight noise limit for general construction work.

The city’s standard nighttime noise limit at nearby residential property lines is 50 decibels, which sounds like a refrigerator. But Denver typically allows 75 to 86 decibels in nighttime variances for construction projects.

How extensive will overnight work be?

In its variance request, Kiewit says “regular construction activity is anticipated during nighttime hours five days a week.”

But the city’s recommendation would allow Kiewit to exceed those heightened limits during major structural work, for up to three consecutive nights at each location. Kiewit is planning more sound barriers, and it would have to put up nearby residents in hotels and provide meal vouchers or allowances.

Brooks, who said he planned to push Thursday for more constraints on Kiewit, estimates there are 270 homes in what he considers the immediate impact zone, or within a few blocks of the aging 1.8-mile viaduct that will be torn down in Elyria-Swansea.

Overall, the $1.2 billion I-70 project, which officially kicked off preparation work last month, is part of a larger public-private partnership overseen by the Colorado Department of Transportation. It calls for the partial reconstruction and full widening of I-70 for nearly 10 miles between I-25 and Chambers Road.

Kiewit has said the overnight noise variance is needed to meet the projected completion date in 2022, since the noisiest work will require partial or full highway closures. During the day, CDOT is requiring Kiewit to keep three lanes open in each direction.

The contractor initially filed its noise variance request for a July hearing, but it quickly pulled back to retool the proposal after neighborhood advocates and officials took it to task for a lack of public outreach. In a statement Wednesday, Kiewit said the revised request reflected its effort to put together “a comprehensive plan … that will protect the community’s interests.”

Decision is up to public health board

The public health board will consider Kiewit’s request during a public hearing at 5:30 p.m. Thursday in Room 389 of the City and County Building.

I-70 meeting intrigue, con't:

3) The board will have a quorum with 5 of 9 members present, so the hearing on the I-70 noise request can go on.

4) By its bylaws, the board can take action with majority vote of the members *present*. This means *3* members can approve or deny. — Jon Murray (@JonMurray) September 6, 2018

The nine-member board, appointed by the mayor and confirmed by the council, could deny the request or add new restrictions beyond what the public health department has recommended.

Already, the city has heard an earful.

Through Wednesday morning, about 30 emails had been received, running more than 3-to-1 in opposition to Kiewit’s request. The handful in support typically cited a hope that overnight work would result in completion sooner.

“I have concluded that, for me personally, the benefits of having this project completed swiftly vastly outweigh the downside of having additional construction noise at night,” wrote Graham Alexander-Thomson, who lives about a block from I-70 on Williams Street.

Document: Recommendation by Denver Department of Public Health and Environment