It’s been an interesting 12 hours: seismic activity in Interior Alaska has really ramped up, causing a multitude of small quakes, and three large enough that we felt and heard them. Last night there was a magnitude 3.5 earthquake around 9 miles from our house, and this morning there have been two more (a 3.2 about 11 miles away and a 2.9 that was only 6 miles away). None caused any damage, but they do shake the house and make enough noise that the dogs perk up. Experiencing tectonic forces so large and powerful is a sobering (and exciting) experience.
There’s a general perception in the lower 48 that California is the most seismically active place around, but the huge subduction zone that stretches from the Aleutian Islands all the way to the west coast of North America causes earthquakes and volcanic activity all over Alaska. The 1964 Good Friday quake (pictured in the photo) was the largest ever recorded in North America, and the 2002 Denali earthquake (which we rode through at the Bird Observatory) was an order of magnitude larger than the 1989 Loma Prieta earthquake that ripped up the Bay Area during the World Series. Most of the major earthquakes are south of the Alaska Range where the plates are moving against each other closer to the surface, but all the pressure creates fault lines up here in Fairbanks and can trigger some fairly large events.
Our house is less than ten years old, but knowing it went through the Denali quake without incident allows us the luxury of appreciating the power of the geologic processes at work without worrying they’ll destroy our house.
Update: 31-May-2009, 21:35. Magnitude 3.8, eight miles away.
Yesterday afternoon while I was brewing beer (more on that later), I took Nika out for our usual walk. We go across the bridge, walk along the north side of the Creek until we get to the confluence of the Creek and the Slough (the “stick throwing spot”), then drop down onto the Creek and walk back. Typically we’ll walk under the bridge and come back up onto land near the red cabin. Yesterday we kept going another few hundred feet until we came across some overflow. It was only a few inches deep and didn’t seem to be advancing.
Last year we got some overflow early in the winter, but by January it seemed to have stopped and we didn’t get anymore until the Creek broke up at the end of April. This year it’s been lightly overflowing in spots around our house pretty much all winter. With all the late season snow, it’s been a good thing because it keeps the depth of the snow on the Creek lower than it would be. I did use snowshoes a couple times because the snow had gotten deep enough that it wasn’t fun to wade through, and Nika had a hard time swimming through it.
In the evening, I got up to get myself a Silver Gulch Hefeweizen, and was surprised to see running water over the whole length of the Creek. I went outside to investigate and take some photos. The water flowing over the ice was about 10 inches deep (you can see it in the photo of my boot on the right). The photo on the left (assuming you’re reading this on my blog and not in an aggregator…) shows what it looked like when I initially got out there.
I walked downstream through the overflow and came to the end of it near the stick throwing spot. It was pretty wild walking through almost a foot of water on top of the ice, and as I neared the bend at the slough, it started getting shallower and shallower. Eventually, I walked up onto the snow and took a few photos as the water advanced.
This morning the water level on top of the ice is up to 14 inches. The low temperature last night was -14°F (and it’s still -10°F as I type this), so the margins of the overflow are already frozen to around ½ an inch, and there’s steam rising from the flowing center. It’s great to hear flowing water again, but that much water suddenly appearing does make me a little nervous. We’re not in any present danger as the low point in the dog yard is easily three feet higher than the current level of the slough, but when a foot of water can suddenly appear over the frozen ice, who knows?
The top of the slough now has some water in it too, but I haven’t walked out on the trail to see how far the water has advanced. Depending on how much more water there is and the average temperature for the upcoming weeks, it looks like our walks on the Creek might be over for this winter. I’m curious to see how all the water will affect the breakup date this year. The weather service is predicting lows in the 20s and highs near 40 all week in Fairbanks, but that probably means lows near zero and highs barely above freezing here in the Valley, so breakup probably isn’t happening this week.
Last winter our vent pipe froze solid and I spent a couple hours in the attic with a heat gun melting the blockage. A couple days ago I noticed that flushing the toilet was pulling water out of the traps in the sink and bathtub, so I knew the vent was getting plugged again. My attempt at a fix over the summer was to put a larger pipe over the vent on the roof so the condensation might happen in the outer pipe, which could be easily removed and cleaned out. Unfortunately, when I got up on the roof today, not only was it impossible to get the outer pipe free, but the growing constriction wasn’t in the outer pipe anyway. Mid-summer my neighbor suggested replacing the section of the vent in the attic with a much larger diameter pipe (6” was his suggestion) and then insulating it. I never got around to it; almost frozen vent pipe; a priori.
The total freezing degree days to this point in the winter season has been 2,258,† which ought to give me a pretty good way of estimating when I’ll have another problem. Thus far we’ve had 74 days with an average daily temperature below freezing, and the average temperature for those days was 1.4°F. That’s below normal for the year: nine of the last eleven weeks have been below average. But the heart of the winter is approaching, so it’ll take many fewer than 74 days to double our freezing degree days for the season.
My first attempt to fix the clog was to insert a heat gun into the clean out and let the warm air from the heat gun melt it (shown in the photo). I don’t think this had any real effect. I kept it going for a little over an hour, monitoring the backside of the pipe to make sure the heat gun wasn’t melting it. But it was around -10°F this morning, so I’ll bet the hot air was pretty cold by the time it rose to the ice. The second attempt was using a pipe snake from up on the roof, but it couldn’t go past the constriction, and even if it had, I’m not sure it really would have cleared out much ice. Finally, I dragged a five gallon bucket filled with hot water up onto the roof. I got about three gallons into the vent before it was filled to the top. At first I was nervous that this wasn’t going to work and I’d have three gallons of water turning to ice in the vent, but the water started dropping slowly, and after a minute, the blockage gave way and hot water came plunging down the pipe. I poured the final gallon or two through the pipe, and came down off the roof.
Tomorrow I’ll put some 2” fiberglass insulation around the part of the pipe that’s exposed in the attic, which should help. And I’ll be keeping my eye on the total freezing degree days for the rest of the winter. Once it gets up to 4,000, I may want to go back up on the roof with another bucket of hot water.†SQL query from my weather database: SELECT sum(32.0 - t_avg::double precision) FROM daily;
Today I brewed my 80th batch of beer, One-eyed Squirrel (named after a one-eyed squirrel that showed up at our feeders this fall). I decided to brew beer earlier in the week and last night I got the brewing water from Water Wagon (a coin-operated water depot where many people in Fairbanks go to get their drinking water). It’s more convenient to brew out by the red cabin than near the house, so I haul a 55 gallon drum of water out there. The water is normally around 40°F when it goes into the drum, and that’s a perfect temperature for the cold water supply used in my plate chiller which quickly chills boiling hot wort down to yeast pitching temperatures; around 68°F. When we went to bed last night it was a balmy 2°F outside, so I wasn’t worried about leaving the water out on the red cabin’s deck.
This morning, as you can see in the image on the left, it was -20°F, and the temperature of the water in the 55 gallon drum had dropped to 32°F. As soon as I started pumping it into the pot for the mash it froze in the lines to the pump. I wound up using a heat gun to keep the pipes and lines thawed while I pumped the water into a drum inside the red cabin where it’s warm. Six hours later when I was using the water to chill the wort, the water temperature was still 32°F. There’s a lot of energy between 32°F water that’s frozen and 32°F water that’s about to be 33 degrees, and I had 50 gallons of water somewhere between those two states all day today.
The brew went well. I double-ground the grains last night, and it paid off, giving me an 82% mash efficiency. Hopefully the yeast will take off later tonight or tomorrow and the beer will be good. It’s the first time I’ve used Cascade hops in several years and I’m hoping they don’t disappoint. In the past I’ve found the flavor to be somewhat soapy, but with the worldwide hop shortage, there’s limited selection when it comes to whole leaf hops. I’ll take what I can get.
This is my first batch using our old refrigerator as a fermentation chamber instead of the chamber I built several years ago. We keep the red cabin pretty cold in the winter, so the fridge is set up with an enclosed light bulb as a heater (just like the old fermentation chamber), but using a fridge allows for the possibility of cooling it down if the fermentation heats up the interior too much (a problem I’ve had in the past with the old fermentation chamber). I’ll also use it to brew lagers at some point. After 80 beers, maybe it’s time to give a lager a try.
We’ve been keeping track of all the animals we’ve seen in our yard, but now that it’s winter, seeing something new is rare. Last month we saw our first great horned owl of the fall season, and today the pine grosbeaks showed up. The males are a bright magenta color (like the three in the photo on the right) and the females are a light olive green color. Not only are they very colorful birds, they have a really delicate song that’s not at all what I expect to hear.
I took the picture through the sliding glass door to the deck, so there’s some glare on the window. Click on the photo for a larger version where you can really see them.