During the winter I have such a different relationship with the Batten Kill. I am not in and out of it every other day or so, and the activities of fish and other wildlife that go on in the cold water and under the ice is closed off from me.
However, I can still learn a lot about river dynamics in the winter by looking at the formation of ice. In very cold weather the ice will form wherever the water is moving more slowly. The areas of the river without ice tend to be where the river is flowing quickly. Sometimes that is where the deepest and strongest current is, sometimes it is a shallow area of rapids. But the ice patterns always tell me something about the river currents that I can use to understand what the dynamics are when they are not as easy to read.
I have a selection of slides to illustrate what I mean. Most are views from bridges since there is a good perspective, and many involve areas where the Alliance and its partners have installed structures to both improve river dynamics and provide cover and shelter for trout. The desired improvements in river dynamics tend to involve creating a curving concentrated flow with alterations of slow and fast water, and alterations of shallow and deep. It is not good when there is just a wide shallow straight channel. The river wants curves and variation.
The slideshow starts looking downstream from the Eagleville Covered Bridge in Shushan, NY - there the current has just made a big curve under the bridge and then comes back across the channel. Note the useful large woody debris further downstream.
Then there is a picture of a rock vane put in by Carl Schwartz of USFWS just upstream of the bridge at the river access -- you can see that it is doing its job of focussing the current into the center, and the water upstream of the vane is quiet and frozen. This indicates quiet water that accumulates sediment deposits.
Then there are two pictures looking downstream from the Rte 313 near Hickory Hill Road in Shushan -- to the right you see a stretch of ice indicating quiet water. This is where we put in a series of rock and log vanes last September -- again they are functioning to concentrate the floo of the river into the center and accumulate sediment deposits.
Next there is a view looking downstream from the Hawley Bridge on River Road off Rte 313 in Arlington, VT. Pretty clear where it is slow water and where it is fast water.
Next is a picture looking upstream off River Road above the Benedict Crossing Bridge -- note split current, and also note very large Irene wood far upstream. Then there are pictures looking downstream and upstream of the confluence of the Batten Kill and Benedict Brook. In the first downstream picture you can see the series of log and rock vanes installed along this reach in 2010 doing their work of focussing the river's flow and improving dynamics.
Finally there are two depictions of the upstream view from the West Mountain or Rochester Bridge on River Road. The island to the right has formed as the water slowed to pass under the bridge. The deep fast current is curving to the left, but there is quiet water at the far left. This is where we put in some large wood structures this past September, in order to create cover and shelter and to protect the bank from more erosion for the landowner. The ice seems to say that both goals may be accomplished.
BKWA Executive Director