Yesterday I went for my first run on Goldstream Creek this winter and noted a very smooth descending line on the elevation diagram from my Garmin watch while I was on the creek. There was a significant overflow event on November 29th, and with the cold temperatures since then, the water on the surface froze solid.

Here’s the plot of creek height and temperature for the last seven days. You can see the overflow event on November 29th, and a sudden drop starting yesterday afternoon.

Usually when there are overflow events like this they are fairly restricted, overflowing in one place for a thousand feet or so, freezing, then overflowing somewhere else. But this event was large enough that I was running on clean ice for almost the entire time I was down on the Creek. In winter, I run with Black Diamond Distance Spikes, and barely slip at all, even on smooth ice.

Here’s the map of my run.

And the elevation diagram. You can clearly see where I dropped down onto the Creek at the end of Miller Hill/Miller Hill Extension at a quarter mile, and then came back up at the Murkowski cabin near mile 2¼. The orange line shows a fitted line to the elevation points while I was down on the Creek.

When I dropped down on the Creek at the end of Miller Hill and Miller Hill Extension, the elevation of the Creek was 562 feet, and 1.9 miles downstream it was down twelve feet to 550. The slope of the line is -5.876, indicating that the Creek drops almost six feet per mile along the course I ran.

Something happened to the ice overnight, at least at our house, so it’ll be interesting to check it out on my run today. The overflow on November 29th was around 4 inches deep, and last night it dropped almost the same amount. Since the surface is frozen, there must have been a layer of air under the ice that was filled with water earlier in the week, but after the water overflowed (and froze), that layer emptied and the ice on the surface dropped back down.