Howitzer Avalanche Control on Mount Snoqualmie

[andyrew]

I'm reposting this from turns-all-year since I don't see it posted here anywhere. I have no relation to Gib or the Alpental Pro patrol, so you'll have to direct questions to them.

 

 

As of today, Tuesday Nov 13th, it looks like we will do live fire targeting this week. Most like it will be Thursday based on the weather forecast and we appear to be getting lucky with the amount of recent snowfall. There should be just enough on the ground to make hiking or climbing very undesirable on the phantom side of the mountain, and also skiing or riding clearly not yet on anyones mind. We'll be updating the snow phone and putting out signs to capture those who show up that morning. We will also have staff at the Snow Lake trailhead for the duration of activities. Snow Lake trail will be left open open for winter walkers, no hazard from above yet with the marginal foot or so of snow on the ground, but we want to make sure everyone in the area knows what's going on. This is good practice for the public info portion of these events, we will not get every target done this time around so there will likely be another session mid-winter. Thanks for the support - G

 

 

Original thread reproduced below:

Hi again from the Alpental Patrol and Snow Safety perspective. We have a few things coming up this fall so I thought it would be best to give as early a notice as possible. Those who pay attention to avalanche work around Snoqualmie Pass will remember the days of artillery being used for Snoqualmie Mountain. Back in the day we would use a 75 mm recoilless rifle when those epic storms threatened to end with a warm up and the bigger paths could potentially threaten the valley floor. If anyone has any photos from 1990 when the Phantom path trashed the shop lot and all the equipment parked there I would love to see them. Several seasons ago we transitioned to a 105 recoilless but did not ever get to fire it at the slopes. We have done the rare helicopter blasting (2008) and also managed the hazard via full closure (2008, 2011) but did not actually use the gun itself. The ARMY is mandating that all programs discontinue the use of recoilless rifles for avalanche control. They no longer test that very, very old ammunition and will not certify it to be actively used. All of the U.S. programs will transition into one type of artillery, which is the M101-A1 Howitzer. It’s a big investment for any snow safety program and with the local WSDOT Avalanche teams also needing to eventually transition from the M60 Battle Tank, it made sense to work together. Since this is a completely different weapon system we have had to do some groundwork to pull it off. We will have to fire from the valley floor rather than up on the Alpental slope-side gun tower so it means some target acquisition work, and establishing indirect co-ordinate capabilities. It’s probably obvious that just when you need to fire, the weather is generally bad. That is the same reason that the helicopter control is not a very good option. Waiting for visibility can just take too long. The bottom line is that we will need to do a targeting live-fire mission at least once in the next couple months. A new sign will be going up soon in the main Alpental parking lot, and both an informational website and a phone info line will provide current control plans and advisories. 425 434 6793

The phone line has actually been in service for a couple years but the message has been consistently the same, “No Avalanche Control Operations are Scheduled at This Time”. Almost everyone is carrying a phone these days so the hot line seems like an appropriate means for instantly available info. We hope to pull off the live firing at a time when there is just enough snow cover to see shot placement effectively but not enough on the ground to make ski touring very desirable. We are thinking early November but we will have to let the actual weather dictate some of that. Right now it’s anyone’s guess, but commonly these early snows don’t stick around and it will still be a little while longer.

I’ll update this posting as we get a little closer to the actual event, and also advise when it’s time to begin the winter uphill touring restrictions in the ski area. Thanks as always -Gib