By Tracy Record

West Seattle Blog editor

A late-night round of sleuthing may help settle the question of what’s behind “The Hum,” which returned Monday night after two-plus weeks – at least, the latest version of it.

If you’ve heard it – listen to see if this is what you are hearing, and note the ship stack visible as we zoom in toward the end:

We shot that video (most useful for audio purposes) from West Marginal Way SW last night, not far south of Highland Park Way, after a late-night round of sleuthing involving Highland Park community advocates plus managers/staffers from a different company – NOT where the video/audio came from – who were trying to determine for once or for all if their operations were to blame.

Quick recap, if you’re just joining us:

Tales of “The Hum” have percolated around West Seattle for years. We mentioned it here in the WSB news section in 2009. It has sparked multiple WSB Forums discussions in the meantime.

But nothing like the sudden explosion of reports around Labor Day Weekend. For a while, we pointed people to the Forums – but the reports kept coming in, and it seemed obvious that this was news.

So we published this story, which went somewhat “viral,” leading to regional-media attention, and then even international notice, particularly when the fish theory briefly surfaced – since debunked, by the way.

The city Department of Planning and Development has jurisdiction over noise, so it investigated.

Then things calmed down and we didn’t hear it, or hear about it … until this past Monday night.

Whatever had caused it before – or at least one distinct form of it – was back, and we wrote this story after reports came in via e-mail, Facebook, Twitter, text, phone, that people were hearing it again.

As had happened back around Labor Day weekend, some commenters speculated the Lafarge plant on West Marginal Way might be a factor. We went down to listen on Monday night (video/audio included in our story), and from what we had heard of “The Hum” – a distinctly rising and falling, oscillating sort of sound – the ongoing sound of Lafarge equipment did NOT resemble that type of sound.

We were contacted yesterday afternoon by Lafarge plant manager Jonathan Hall, who said he would do whatever it took to figure out for once and for all if his plant was responsible. He already had talked with some Highland Park community members, including HP Action Committee co-chairs Billy and Carolyn Stauffer, and was hoping to set up an experiment if it happened again Tuesday night: Verify the sound from Highland Park, then have someone at the plant shut down their equipment (with on-site verification too), and see if that changed anything.

When “The Hum” started up again at mid-evening yesterday, the plan was put into place. We got a call and went over to Lafarge to see, and hear, what would transpire.

Meeting at the plant entrance, we learned that manager Hall had arranged to go uphill with HP resident Kay Kirkpatrick, rendezvousing with Carolyn Stauffer; WSB co-publisher Patrick Sand went along. I stayed at the plant with Billy Stauffer and other Lafarge employees awaiting a radio message/phone call as a signal to shut down the equipment if the sound was still audible in HP.

Of course, as Murphy’s Law would have it, it wasn’t.

Everybody waited for 45-plus minutes. I was in the plant control room with some genial gentlemen who even made us coffee. Nothing changed at Lafarge – but what was audible there, as we recorded, was the same steady sound I’d heard and recorded the night before from across West Marginal Way (featured in our Monday night story). Here’s what it sounded like last night, standing right on the grounds of the plant:

The Stauffers had already checked out the ship to the south – which they say is the CalPortland terminal – and voiced their belief it sounded like the culprit. (It should be noted, the ship suspicion also was mentioned in a comment during the early-September coverage.) So when we left Lafarge, we went down the road to see what we could hear.

That’s when we recorded the video/audio, above. We didn’t trespass – just pulled over alongside the east side of West Marginal Way and aimed the camera toward the ship whose stack was visible down a long entry drive.

The sound was not audible a short time later from Riverview Playfield, we should note, where we had heard it the night before. The Stauffers kept monitoring into the night, though, and say they matched it around 12:30 am.

The ship, as identified in this comment yesterday and verified via MarineTraffic.com, is the Silver Lake. As of this writing at midmorning Wednesday, it is still there – you can see on this MarineTraffic.com page that its stack has the “B” you see toward the end of our first clip.

Lafarge says the Silver Lake was not making a delivery for their facility but they use the same type of ship, and since they have empty dock space, this one is due to dock with them after it’s done offloading further south. Their last delivery from any ship, plant manager Hall says, was August 25th. But a ship like Silver Lake, he says, was also on the Duwamish around Labor Day.

So now what?

Zeroing in on a likely source is just part of the puzzle. Questions include whether the sound of the offloading operation is breaking city rules. That’s up to the city to determine – and they continue to collect complaints. (They had checked out Lafarge previously, by the way, per the response added to our story yesterday, and found nothing.) If you have been disturbed by the sound, they ask again that you report it directly to them – contact info is at the right side of this page.

The HPAC co-chairs are continuing to investigate via the terminal where the ship is docked. We will hear more from them later, including at tonight’s meeting (7 pm, Highland Park Improvement Club at 12th/Holden). We also have an inquiry out – and any new information during the day will be added to this story.

ADDED 7:46 PM: We’re at the HPAC meeting, where the first half-hour or so was spent on The Hum. The Stauffers said that they had just received a statement from the CalPortland manager with whom they had spoken earlier, and he had sent this statement:

We learned for the first time today that our operation is a suspected source of the West Seattle Hum. We have begun investigating the situation to confirm these suspicions. We will cooperate with the community and local agencies to take appropriate steps to address the community’s concerns.

More in a separate story on the HPAC meeting, after it’s over.