The numerous wildfires currently active in interior Alaska have made it a pretty miserable last day of the holiday weekend (Independence Day was Thursday in the US). The Fairbanks area is blanketed in smoke so badly that there’s a dense smoke advisory in effect and the local hospital has set up a smoke respite room for people with respiratory issues.
Most eyes are on the Shovel Creek fire NW of Fairbanks, which is burning very close to residential neighborhoods in mature black spruce forest, which naturally burns every ~100 years or so (plus/minus a large interval). It is managed by a Type 1 team – these are nationally managed in the US, and have the largest amount of experience and resources. There have been regular public information meetings, and the fire even has its own YouTube channel.
I live about 30 miles east of town, and over here, even though smoke these days comes from any of multiple fires in the wider area, the one we’re most concerned with is the Nugget Creek fire. It’s roughly the same order of magnitude as the Shovel Creek fire (a little smaller – 7000 acres / 2800 ha as of today, and growing – but unlike its companion, has not received any suppression activity at all, even though it’s only about 10 miles (16 km) from a residential area.
Why? This has to do with how decisions about fire management are made in Alaska. All of Alaska is divided into one of four fire management options. If you follow the link you’ll see that most of the remote areas are in the “limited” option. Here, fire is by default allowed to fulfill its natural ecological function, though known cabins and infrastructure is being protected by firefighters on the ground and from planes. Also, reconnaissance flights are being carried out, and fires are monitored. On the other extreme is the “critical” management option, where all fires are immediately suppressed. Towns and villages are covered by these. In-between, there are two intermediate options, “full” (covering the major road corridors, mining areas etc.) and “modified”. (These options are used for prioritization – there is no mechanical
The Nugget Creek fire started in the Chena River State Recreation Area, in a location that is in the “limited management option. Here’s a map of the fire and how it is just nestled into the green, “limited” area. The fire is in red on the right, with the spots indicating where active fire was detected by satellite imagery. The fire has been pretty active on nearly its entire perimeter.
But it is still nearly entirely in the area that belongs to the limited management option. To the north, the full option starts at the Chena River and/or Chena Hot Springs Road, approximately. To the west, the modified option starts at the south fork of the Chena River (the confluence is where green, brown and blue areas meet). There are some fire service staff assigned to the fire, who have been continuously monitoring where the fire is relative to river/road in the north, and also have set up sprinklers to protect a public use cabin on the south fork of the Chena River (Nugget Creek cabin).
I’m pretty sure that we’ll see some drops of water or retardant if the fire service thinks it may jump over the river or road in the north. There are more reasons to think it won’t spread too far west or east: not only is the western side quite swampy and full of sloughs (and of course a small river), but there are also recent fire scars in the area, which would slow down a fire. The blue area is already within the scar left by the 2013 Stuart Creek 2 fire, and the area east of the fire burned in 2009 or 2000:
So what do I expect will happen? My guess is that the fire will burn out a good part of the triangle between rivers and old fire scars. It’ll be several days before we can expect rain, so smoke will stay terrible for a while.
In any event, Nugget Creek will be an interesting case study for testing models of how fire spreads: It’s one of the few fires that will be relatively easily accessible on foot (once it is completely out of course!), as it has reached Mastodon Creek Trail in the east and is visible from two bridges over the Chena River. And it will have been essentially unsuppressed, ie left ti its natural progression, at least until now.
Boreal Perspectives 