An Early Season Hike up West Fork of Oak Creek

It’s only the second week in April and that is still early in the season for hiking up West Fork of Oak Creek. There are numerous water crossings along the 3.3 mile maintained trail; these are usually easily crossed on stepping stones or small logs placed across the stream. Beyond the maintained trail, however, there are several water crossings that are simply too large for stones or logs and one must wade through the water. This early in the season the water is still chilly—and there was even some residual snow in the shadier parts of the canyon.

West Fork Oak Creek ("The Subway")
West Fork Oak Creek (“The Subway”)

We were especially interested in learning how the canyon had fared during the heavy rain events that occurred in January and February. Flagstaff, for example, received three times its normal precipitation (6.51 inches vs 2.16) in the month of February. And there were other periods of above normal flows in Oak Creek; e.g., mid January, early February, mid February, and an extended period in March that corresponded to snow melt at higher elevations.

USGS gauge data for Oak Creek showing several high flow periods this winter.
USGS gauge data for Oak Creek showing several high flow periods this winter.

Our interest ties back to the Slide Fire that occurred in this area in May 2014. In the aftermath of the burn, heavy loads of silt and ash flowed from the higher elevations and into the canyon. This turned a beautiful canyon with deep pools in the sandstone into a ash-blackened, silt-filled creek. For those who have long cherished the beauty of this canyon the results of the fire were heartbreaking.

Silt and ash have been flushed from this swimming hole in West Fork Oak Creek.
Silt and ash have been flushed from this swimming hole in West Fork Oak Creek.

But we knew that, in time, rain would scour out the ash and silt and return the canyon to its former pristine self. But normal rains were simply not enough to accomplish this. This would require sustained above-normal amounts of water. We traveled up the canyon in early January but, even then, most of the silt from 2014 was still there. But the heavy rains were about to start.

Another narrow section of West Fork Oak Creek that has been cleansed of silt and ash.
Another narrow section of West Fork Oak Creek that has been cleansed of silt and ash.
This large pool was filled with silt after the fire. Now it is finally clear again.
This large pool was filled with silt after the fire. Now it is finally clear again.

We were very happy to find that the heavy rains and runoff had finally cleared the canyon of silt and ash. Black, muddy shores and beaches were cleansed and replaced with deep, light-colored sand. Silt-laden pools were scoured out back to the sandstone bottoms and filled with beautifully clear water.

Large pool in West Fork Oak Creek.
Large pool in West Fork Oak Creek.

The canyon had finally recovered from the aftermath of the Slide Fire.

A visit to West Fork Oak Creek after the Slide Fire

The Slide Fire started on May 20, 2014, and was fully contained 16 days later. In the aftermath of the fire, Coconino National Forest closed much of Oak Creek Canyon for safety reasons. Four months later, on October 1, the restrictions were lifted and recreational activities resumed.

We wondered how much—or how little—of West Fork Oak Creek (WFOC) had burned. There had been some information during and just after the fire indicating that in the lower section of the canyon there was only light to moderate burn severity and only over a small percentage of the canyon. (Detailed map from InciWeb.) Farther up in the headwaters there had been widespread low intensity burns.

Typical burn scar seen in the lower reaches of West Fork.
Typical burn scar seen in the lower reaches of West Fork.

So, finally, we hiked up WFOC to see for ourselves. The information was essentially correct and only small portions had burned and at low intensity. The canyon had survived. But there was still significant damage. Because of the burned areas farther up canyon, heavy rains this summer caused a lot of soil and ash to wash into the creek and flow downstream.

The creek channel was filled with silt and black ash. Where once the creek bottom had been smooth sandstone it now had several feet of silt and ash with deep channels carved through the silt.

This will slowly evolve back to its original state as winter rains and summer thunderstorms over the coming years flush out the silt and ash.

On a brighter note, we did see a late crop of ripening berries along the creek. Tasty!

A late season crop of ripening blackberries along West Fork.
A late season crop of ripening blackberries along West Fork.

One of the most significant changes occurred at the end of the West Fork Trail. The trail ends around 3.3 miles from the trail head where the canyon narrows and deep water is found from edge to edge. To travel farther upstream requires wading through water that is thigh deep in places. Most hikers turn back at this point; a few hardy hikers accept the challenge of water and no trail and continue upstream for many miles.

End of West Fork Trail in 2012 with water-filled channel.
End of West Fork Trail in 2012 with water-filled channel.
End of West Fork Trail in 2008 with water-filled channel.
End of West Fork Trail in 2008 with water-filled channel.
End of West Fork Trail in 2014 with silt-filled channel.
End of West Fork Trail in 2014 with silt-filled channel.

That has changed now as silt fills the slot canyon and a firm trail now exists where it once was only water.

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