partially channelized stream

[Tups]

K-Bob: The channeling would have been not only to remove logs and other obstructions but to reshape the channel, making it straighter and steeper, thereby theoretically better at passing high flows. Bed load material would have been removed from the channel and placed in a berm on the side of the stream, in this case, along the left descending bank (the floodplain side). Your ground photo seems to indicate such a berm, though there are trees now growing upon it due to its age (about 45 years old if in response to Agnes).

When you come across such a straight, wide channel, look for the tell-tale berm of cobbles and boulders along the stream, often-times covered with vegetation. It may be immediately adjacent to the channel or some few yards beyond (however far the bucket could reach.) There are a lot of these old berms in NEPA, all of the same age (45 y.o.) It is impossible to over-estimate the amount of stream channelization which occurred in the wake of Agnes.

 

[k-bob]

Very interesting I thought the channeling might be older and from logging.... thanks

 

[Gone4Day]

k-bob wrote:
If the channeling was done as part of logging it might be more than a hundred years old. But it looks quite crisp, at least in some stretches, in the original post lidar image ... that image taken w/in last ten years

Just to be clear, the preview image at PASDA is 1/9 arc-second radar data from satellites. It’s good stuff but doesn’t have near the resolution of LiDAR. Radar goes through clouds, leaves, wood and most other structures though. LiDAR, not so much.

Underlying the preview there’s actual LiDAR data but you have to download to view. Coverage is spotty and you’ll need a program that can read and display the specialized, geo referenced files though.

 

[k-bob]

Thanks, G4D, didnt realize the PASDA preview is radar not laser/lidar.

Any thoughts on maps for finding/using goat roads and studying stream channels appreciated. For ex., if the PASDA preview's radar works well thru vegetation/trees, it may be useful even if lower resolution than lidar. Also, by selecting a bing basemap, the PASDA preview map displays the cursor's GPS coordinates, which allows input of the location of goat roads to a handheld GPS (or phone, I guess). Then you have a map in your hand with unmapped roads on it.

Any thoughts on a better way... for ex., is there higher-res radar than the PASDA preview that isn't too complex in use?

thanks again.

 

[troutbert]

k-bob wrote:
Very interesting I thought the channeling might be older and from logging.... thanks

The two things are not at all mutually exclusive.

Many streams were channelized early and often.

So they were first altered back in the 1800s, but also from then up through modern times to the present.

(And in southern PA there were probably a great many streams highly altered in the 1700s.)

 

[k-bob]

Tb I see your point!

 

[k-bob]

There a few things online about the 1871 PA " act to allow improvements on creeks and rivulets"

http://tinyurl.com/hj89xkz

Some streams that seem quite remote, for ex heberly run in sullivan County (tributary to the east branch of Fishing Creek), seem to have been channeled .... see post 3 and zoom in on heberly.... channeling eventually ends way up high where two tribs meet

freeze heberly video below at 7 seconds where it shows downstream view in flood... pretty smooth channel....

https://www.youtube.com/watch?v=zXgUnvfIzHw

 

[henrydavid]

Hi K-bob, how ya doin? I've fished Heberly Run and it is very rugged terrain. All I know about the area is there was logging done up there.

 

[k-bob]

Hi yeah I am good, still losing fly rods 🙂

 

[henrydavid]

I never got back to that spot we were at, I was upstream and on the other side last year but water was up and there was no way to cross, water up to the banks and nothing but ticky brush on the stream side. It's probably still back there.

 

[Chaz]

That watershed in particular has been repeatedly subject to flooding since Ivan. Last time I fished below the reservoir, I caught nothing. Generally the fishing can be good. I've fished up the reservoir but not above. The watershed is pretty steep.
The channeling we see in the images has likely been repeated from as long ago as the first logging, probably early 1800's, the area was settled by the late 1700's. There was a major stream cleaning effort after one of the big storm, I think it was Ivan. I even heard people talking about removing the islands from the Susquehanna River, they were saying that the islands were causing the flooding.
Can you imagine? I'd like to fish Painter sometime.

 

[Chaz]

Looking at the flood plain on the gray map, I see what may be remnant channels from pre-channelization.