Wednesday, September 16, 2009

James River at Arcadia - September 2009, The Power of Water

I chose a cloudy, warm, and humid late-summer afternoon for an hour's paddle on the James River, Virginia, near the Arcadia boat access. You can read more about the Arcadia access here. Parking for about a dozen vehicles and gravel path to the water provide access to a reasonable amount of flatwater in the downstream direction, enough for 45-60 minutes on the water, including poking around time.

Water levels today were much lower than when I visited this location in the spring, and numerous boulders were jutting out of the water along this stretch. It's possible to paddle upstream from the access point, at least for a short while, but I chose to head downstream today along a relatively quiet stretch of flatwater. Besides two people bank fishing, I had the river to myself.

Downstream from the boat access point and around a long meander, I came upon a small creek entering the James.


It's a small creek which flows out of the adjacent mountains and beneath a railroad bridge before emptying into the James. The lack of recent rain has reduced its flow to barely a trickle. Listen to and watch a short (15 second) video clip of water from this creek flowing over some rocks into the James River:

video

The force of the water today was barely enough to move a rock the size of a pebble. What's interesting about this location, however, is the size of the bar immediately downstream from where the creek joins the James River. In the picture below, you can see the creek spilling into the James in the left-center of the photo:


A large bar of boulders extends downstream, formed when the river and creek are in flood, and large boulders are brought down the creek out of the mountains by the force of the water and the creek's steep gradient.


When faced head on, the bar looks like this:


The bar itself is large enough to act like a peninsula, and it's possible to paddle around it to the backside. In late summer, much of the bar is overgrown with vegetation and young trees:


One can image the incredible force of the water necessary to move these large boulders, and the many tens of thousands of years needed to build a bar of this size. And, really, the amount of rainfall needed to create a flash flood sufficient to move large boulders - something we haven't experienced in recent years, given the persistent drought.

View this location in Google Maps by clicking here. Note the bar in the satellite photo, taken when water levels were relatively high and flowing partially over the bar.

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