Periodic Spring - Afton
(0 Ratings)
RATING: Easy hiking, well suited to most.
LENGTH: 1-2 hours / 1.5 miles round trip.
MAPS: Red Top Mountain, WY
SEASON: Spring through fall, though fall is best.
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WAYPOINTS:
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| Trailhead | 12T 511504mE 4733007mN | |
| Bridge | 12T 512380mE 4732683mN | |
| Spring | 12T 512392mE 4732423mN | |
Hype
Periodic Spring is a very unique geological feature. It is a cold water geyser, that in low flow times of the year (such as late fall and winter) will flow, then cease to flow for 10-20 minutes, then flow again.How does this work? The theory is an underground lake is continuously being fed by springs. The lake has a passage out to the entrance of the Periodic Spring, but is convoluted in such a way as to create a siphon. In high flow periods, the lake is overflowing strongly enough the spring runs continuously. In drier times, however, the flow stops while the lake fills enough to force water through the passage. This creates a siphon effect, and drains the lake to a level to low for the siphon to pull water, and the refill/purge/refill cycle begins again.
This fascinating oddity is only known to occur in handful of other places in the world, with Periodic Spring being by far the largest of them. It provides a short, family friendly hike if you are in the area. Even if the spring is flowing continuously it is a lovely hike.
Trailhead
From downtown Afton, go east on 2nd Ave. Follow this road for 5.1 miles to it's end. After about a mile it turns to dirt, with a campground on the right. From here on, it parallels Swift Creek. The dirt section is generally passable by any vehicle. En route you will pass Swanee Falls on the right, and Swift Creek Tower on the left. (The obvious tower a few hundred yards from the road.)The road ends in a large parking area with a pit toilet. This is the trailhead.
Route
From the parking area, follow the now gated road as it parallels the stream. It is a short walk (10-15 minutes) to a large concrete water processing area. Periodic Spring is the waterfall coming down the gully on the right, and visible from the concrete tank. Just up from the concrete tank a bridge crosses the stream and there is a picnic table. Follow the trail as it goes up the edge of the gully to the spring proper.It goes without saying, but never try to enter the spring. Even if it is not flowing, it will start soon and the potential for drowning is high!
Photos (click on photo for more detail)
Maps
