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  1. #1
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    Trail seasoning, drainage etc. for PNW year round trails

    Hello. This is my first post so excuse me if this has already been explored/answered (just send me a link to the relevant thread.)

    I have been building trails in western Oregon for several years now. Mostly solo but in coordination with the Forest Service on occasion.

    My problem is drainage. I build bench cut, sloped trails and try to put in enough drainage paths and grade changes. Nonetheless I still get a fair bit of rutting and erosion from wet weather riders. I could certainly do better, dig more, make more places for water to escape, create even more grade changes etc. but before I go crazy turning what I call "good" into "perfect" I wanted to know if it is likely to work.

    I recently learned about the "seasoning" of trails and this makes sense to me. The soil I work with is largely organic, the clay is just too deep to reliably use or get to. There is not a great amount of rock either and bringing it in is not an option. So, I can do some armoring but not a tremendous amount.

    My question is twofold:
      • Can anyone comment generally on big picture approches to such conditions, including the use of seasoning (in particular for berms and other built up elements) and drainage structures/regimes (ie. Is there a best place to prioritize use of limited rock)?
    • Is it realistic/feasible for a one man show (without rock and gravel to bring in) to build a trail that will hold up to Oregon winter riding without building ladders over the more vulnerable spots?

    Thanks for any help with this.

  2. #2
    humber river advocate
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    you can use a composite geotextile system with grid in it. it stabilizes the ground and facilitates drainage. i've also invented a special sub grade drainage layer that stabilizes the ground over very soft areas and drains extremely well... though the down side is that this all costs a bit of cash.
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  3. #3
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    Thanks for the response. I would love to learn more about these systems. It might give me a better sense of how to think about drainage generally. That said, I couldn't use such systems on the trail I am currently concerned with. I don't have much real budget beyond the tools and some nails/screws.

    As I have studied the trails more while building I think I am learning that there is (and what it is) threshold for what kind of grade this environment can handle during winter riding (if at all.) It seems like there is a tipping point at which a very conservative grade (lets say 5%) that appears to hold up becomes unsustainable (maybe 7%). A very subtle, just noticeable grade change early in the spectrum. even short sections (less than 12 feet) seem to lose their substance if they are built at or above this grade. makes me think I would need a significant amount of ladders to shore up what I thought were well designed grade sections already completed and change the remaining trail to a much more conservative layout.

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