Cul-vert Ops

[Swattie87]

Made it out today to catch my first few fish with the 2016 license. I usually try to do an afternoon of "culvert hopping" on this group of small streams once every Winter. I've found that fishing these types of spots in Winter is often a fairly reliable way to catch a few fish when the weather, and conditions are otherwise less than ideal. In my experience, small stream freestone Trout seem to congregate in deep, slow water holes in the colder months. Culvert holes usually tend to be a good spot to fish regardless of the time of year, but in Winter they have the added bonus of usually being fairly easy to get to and if you have a cluster of them close to one another you can skip around to them in the relative comfort of your vehicle, while not having to walk (in the cold) the less productive Winter water in between.

I fished a total of 7 culvert holes on 3 different streams today, and caught at least one fish in 6 of the 7. In the one I didn't catch a fish in, I spent about 5 minutes busting through brush and thorns to get into a proper casting position from downstream of the pool, only to have a gentleman and his dog cross the culvert on the walking trail right as I was lining up my first cast. Very possible that one was spooked before my line hit the water. Didn't turn up any true "pool bosses" today, but got the 2016 skunk taken care of and caught a few decent Brookies.

 

[sarce]

That looks like a blast. The third pic down looks really familiar but I don't recognize anything else, so I guess it is my imagination.

I've always wanted to do drive-by culvert fishing: have one person drive, while the other person leans out the passenger window and does a bow and arrow cast into the pool. I think it can be done.

 

[dc410]

Nice! Looks like a great way to start off the new year, Matt. Those are some pretty sweet looking cul-verts.

 

[troutbert]

There's a big culvert replacement movement going on. How that will impact the types of pools shown in the photos is a question worth asking.

The purpose of the culvert replacement movement is to improve fish passage. But in some cases they may get gains in fish passage, while losing pool habitat.

The ideal would a structure that provides both fish passage and pool habitat. And that is probably possible, but it's a design challenge. Anyone have any ideas?

 

[bjb27_99]

Very nice Matt. I use that approach quite frequently when I'm visiting the in-laws in Vermont. Up there, there are lots of real, real small streams not really worth the effort that have big culvert pools that are worth the effort. Makes me wonder how many culvert pools I could hit in one day if I only fished the pools...

 

[Swattie87]

troutbert wrote:
There's a big culvert replacement movement going on. How that will impact the types of pools shown in the photos is a question worth asking.

The purpose of the culvert replacement movement is to improve fish passage. But in some cases they may get gains in fish passage, while losing pool habitat.

The ideal would a structure that provides both fish passage and pool habitat. And that is probably possible, but it's a design challenge. Anyone have any ideas?

Bingo tb. The 6th picture down is essentially of a brand new culvert. It replaced an older style culvert that washed out in the 2011 floods. I thought I had pictures of the old culvert, but I don’t. IIRC, the old culvert had a small plunge, and it definitely produced a deeper, and slower hole below it. The new culvert (as pictured) eases fish passage as there is no plunge and essentially a natural stream bottom within the culvert, but in doing so it turns the hole into more of a slowish run on the right, with an eddy on the left. Nearly all of the flow comes through the right opening. Coincidentally this is the one spot I did not catch a fish yesterday…again could have just been spooked by the gentleman walking with his dog however though too. The existing deep spot from where the former plunge used to be is still there, but I suspect that over time the constant current on the right without a plunge will slowly fill that in and shallow it out.

Cool YT vid discussing culvert theory in respect to fish migration in Appalachian Virginia. This one might have been posted on PAFF before, can’t remember. They basically suggest a mild plunge is ok (and perhaps even desirable in terms of habitat) as long as the pool provides sufficient depth and distance to allow the fish to get a bit of a running start to jump it. From there it’s a function of gradient, length, and surface structure of the culvert itself…Less steep, shorter, and with a more natural stream bottom like surface being the desirable traits to ease fish passage.

https://www.youtube.com/watch?v=i25Gv0gptMw