MTBA Trail Guidelines

Sekt

Sekt

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Hi all,

Interested in some thoughts and discussion on the "Level of Trail Exposure" mandatory criteria that is part of MTBA's Trail Difficulty Rating System (conveniently found in PDF format here).

These are considered the new standard for trail building in Australia, but the exposure criteria feels significantly distant from the reality of mountain bike trails. Understandably they can be viewed as a guideline rather than a prescriptive standard, but that isn't a particularly satisfactory approach from a land manager's risk management perspective. By the standard, a dark blue trail has "exposure to either side of the trail corridor includes downward slopes of up to 25%" (and a green trail is required to be less than 20%). I'd be curious to know how many blue trails trails through any kind of hilly or mountainous terrain actually fit within these guidelines. While I haven't looked closely, I'd suspect that not much of Derby conforms to this, and that's pretty much the flagship trail network in the country.

Has anyone else run into issue with this particular part of the guidelines? Am I being unreasonable in my expectation of a blue trail, and should naything that isn't on gently sloping terrain be considered a black trail? Is that representative of modern mountain biking?

I'd be really interested in hearing your thoughts!

(And just for sake of clarity, a 100% slope is 45 degrees, and 25% is 14 degrees)

Edit: Title to reflect wider trail difficulty discussion
 
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They seem ok, prob more trails need to be blue with BLK outline, when u look even BLK has only 30cm drop, which prob isn't that much in this day , the difficulty prob needs to be set harder imo, 10% grad is a fair bit for climbing and descending..I don't see too many in vic which descend above 10% consistently, the macedon enduro trails vary from 11-18%, I find them some of the steepest around which are non-DH trails..Harcourt pretty much all below 10% grad, yet done of them seem steep/fast. I think the single BLK desc. Is a bit easy, people expect them to be harder in reality.
 
The trail exposure is dealing with the "Firm and level fall zone on either side of the trail corridor", meaning the side-slope of the terrain the trail travels through. So it's not impacted by the gradient of the trail itself.

Which means that you could build a 3m wide trail at a very gentle 2% gradient and if the side-slope exceeded 10% then it would be considered a blue trail (rather than green, as I would expect). That doesn't make much sense to me.
 
Trail ratings are all over the place and I don't think this document captures the reality.

On the trail gradients, A lot of fire roads would fails the trail exposure part. It also doesn't specify for what length. Some green family trails will have a ditch adjacent which would presumably make it a blue. A stupid example but that direct application.

Part of the consideration should be a 'combined' score of risk vs consequence. For example, risk is the difficulty features of the trail (jumps, roots, potholes etc. vs the consequence (what happens when you fall - the gradients adjacent). If the trail features are mild then having a steep fall to the side is not a big deal. If it's an unavoidable jump into some roots then followed by a drop, then yeah the gradient of the sides matter a lot.

Trails are a funny beast and having a prescriptive method is quite hard. You really have to ride it to know. Some considerations it completely misses are:
  • Connection of features. How close are the features stacked together. Blue riders would easily be able to navigate a drop, roots and a jump, but string the lot together and the difficulty increases.
  • Speed. A lot for trails are hard but low speed so if you crash, it's not too bad. Others are easier but very fast- if you crash it's going to be epic. Gradient alone does not account for this variable.
 
Yep, I agree on all those points.

I understand that distilling all the nuances of trail ratings own to an easily digestable and understandable set of criteria is very difficult, and quantifying things like speed and the flow/connection of features is a near impossible task. However, it's problematic when the document that is intended to be the recognised guidelines from a national organisation appears to be so distant from the on-ground reality. I think it's something that needs to be corrected and updated, particulary as they list it as a mandatory criteria.

Discussions amongst co-workers has also highlighted the need for some qualification of how riders should approach an unfamiliar trail, particularly in regards to determining its difficulty in relation to their riding ability. A slow-speed ride through will allow a rider to identify b-lines and rollable features, and so safely ride the trail within their abilities. If the same rider goes full speed on their first run, they may quickly find themselves out of their depth, despite there being no physical change to the trail. We're adopting the bike-park addage of 'Pre-ride. Re-ride. Freeride.' to help push that message.
 
Often it not the gradient that get's you when you go off track but the debris that makes you stop quickly. It's all fun an games charging through the bracken until you find a log or wombat hole and exit the bicycle at speed.
 
Sekt said:
However, it's problematic when the document that is intended to be the recognised guidelines from a national organisation appears to be so distant from the on-ground reality. I think it's something that needs to be corrected and updated, particulary as they list it as a mandatory criteria.
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A good way to deal with that is trail score based on the document with some changes to improve it, but then add some subjective criteria from established trail graders (i.e. folks that build them) establish a panel of some sort.

Trail gradings in Aus are all over the place. There is no way lysterfield comms games black is harder than some of the blues at Harcourt for example.
 
Calvin27 said:
Part of the consideration should be a 'combined' score of risk vs consequence.
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I think this is the best way to go and it also reflects the contemporary approach to management of risk in workplaces (and likely to be familiar to land managers). It sort of allows you to apply a layer of 'common sense' to things, and also lets you have more challenging features (with B lines) on easier trails where the conseqeunce of crashing is less severe. A gap jump just before a rock garden vs a jump with an open grass patch beyond it sort of thing.

If the guidelines get too prescriptive, I'd suggest it becomes harder to get a consensus on what can and can't be built because of subjective interpretation of the guidelines. The exposure criteria looks like an intersting one, as it seems to ignore the flora that might be present that could stop a rider from plummeting down an embankment. Being a 'mandatory' MTBA criteria, it could be better qualified than a simple measure of slope to include the mitigating factors. Or is this wrapped up in the definition of 'level of trail exposure' - a side slope that's going to be hard to avoid if you do come off?
 
I should clarify that I'm approaching this from a land manager's perspective, rather than an outside or advocacy group. So risk analysis is part and parcel of what we do, and is why this quesiton is being raised. The idea behind a standard (or guidelines in this case) should be that they're effectively a pre-developed risk matrix.

Given the lack of a Australian Standard for mountain bike trails, the Trail Guidelines are the next best thing as a nationally recognised document from a national respresentative body.

Calvin27 said:
A good way to deal with that is trail score based on the document with some changes to improve it, but then add some subjective criteria from established trail graders (i.e. folks that build them) establish a panel of some sort.

Trail gradings in Aus are all over the place. There is no way lysterfield comms games black is harder than some of the blues at Harcourt for example.
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My understanding is that the guidleines were developed by a very panel such as this, in order to avoid the issue with gradings being all over the place. So I'm just tring to figure out if their decision on these thresholds for trail exposure are sensible and grounded in real-world situations. Because to me a 25% side-slope on either side of a trail is very mellow, and exceeding that shouldn't immediately change a blue (or green) trail into a black trail.

The perspective of our people involved in our trail projects (experienced builders, riders and project managers) is that the numbers are too low, which becomes a problem when the Trail Guidelines document is kinda meant to be the national benchmark for land managers and trail builders.

Nambra said:
...plummeting down an embankment...
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The problem being that the prescriptive thresholds given for a blue trail are not really anywhere near this risk. In fact they're so mild that they're completely restrictive of the kind of terrain you can build a trail in without it instantly becoming a black trail, regardless of the width, gradient or features.

Appreciate all the thoughts!
 
Sekt said:
Because to me a 25% side-slope on either side of a trail is very mellow, and exceeding that shouldn't immediately change a blue (or green) trail into a black trail.
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Anything adjacent a river would immediately fail lol. (main yarra trail)
 
Great to hear that a land manager thinks the new guidelines are too tame!

The updated MTBA guidelines don’t state whether short sections of trail can have steeper side slopes do they? You can have an unavoidable 600mm wide bridge over a creek 1m below on a blue/black trail, but not 600mm wide singletrack with a 25% side slope - seems a bit inconsistent from a risk POV.

Guidelines are beneficial for builders (and the trail rating system is great for riders), but they shouldn’t prevent an experienced builder from making the most of the available terrain features and creating a unique riding experience.
 
Well, people who work for the organisation who manages the land think they're too tame at least!

We need to find a solution that works from a risk management point of view, and the national guidelines don't allow us to do that without either absolutely restricting where we build, or over-grading everything to a black trail, and thus rendering the concept of trail grades completely irrelevant.
 
The key wording from a land management perspective is "guidelines".
A "guideline" isn't a standard.

MTBA originally set out to create a mountain bike trail standard as per AS2156.1 for walking trails.
It quickly became apparent that MTB trails were much more complex beasts than walking trails and somewhere in the process, there was a direction change.

I was directly involved in some of the discussions relating to this TDRS doc (and the full document that accompanies it) and essentially, as has been pointed out earlier in the thread, it was way too hard to create an easy reference table that was simple.
(I wonder if somewhere, MTBA was supposed to use degrees instead of percentage side slope for fall height - I may send them an email and refer to the IMBA Australia TDRS 2014 which allowed for 30% green, 50% Blue and no limit Black).

Our dept uses a risk matrix in the back end and has a Statewide Trails Officer (might be me) who grades all trails within our tenure for the entire state (this hasn't happened yet, largely due to COVID-19 but also due to time). There is a VISITOR SAFETY FRAMEWORK (VSF) which sits behind the TDRS and guides the levels of inherent risks that visitors can be exposed to.

In our investigations as to whether it was worth adopting this TDRS, we printed off a set of the MTBA icons and placed them out in parks to have a look at whether they worked with the edge colours. It was decided that the thin border was pretty useless and we have modified the icon set to have a diagonal split (below).
This still isn't perfect for those who have difficulty with definitions between Blue and Green but adding thick lines in between made it worse.
(We also don't have any double black diamond trails in our reserves as we manage parks which allow cycling, not MTB parks).

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Thanks for the reply!

We actually decided against adopting the in-between ratings (though I like your solution), as we felt they added an unnecessary level of confusion for anyone who isn't already familiar with the simpler five-rating system. We also wanted to be able to integrate it with our grading for walking and shared use tracks, which means we can use the same symbols for all user groups, and keep our signage a little less cluttered. Educating our various trail users on the system and what it means is an ongoing project, but I think it's an inherently better visual system than the walking track class system and its associated symbols.

Agreed on the guidelines v. standard aspect, but in that respect it seems strange to include trail exposure as a mandatory criteria, which is naturally given a lot more weight within the guidelines. It's a lot easier for us if we can adopt the guidelines as-is and have them as a recognised document to point towards when doing trail audits and risk analysis on new trails. Our solution will be to develop an internal statement about why we've made our own adjustments, but it struck me as strange to have to do that for a mandatory criteria because of such a seemingly large difference in what we perceive as a safe side-slope.

You may be right on the percentage/degrees mix up. We've been bouncing around 55% as the ballpark exposure limit for a blue track, and 25 degrees is close to 45%, which seems a bit more reasonable. We've contacted MTBA to discuss it, so maybe they'll be able to clarify.
 
I agree on the exposure not being very realistic, but I do like the addition of a "Dark" green and blue trails as there are those trails that are borderline the next grading but you don't want to put people off due to the higher rating or on the other hand have people who think that because it's green that means beginner and that I have just started riding a bike so I should be able to ride everything on that trail.
I also like the trail rating that Maydena uses where it is also rated in the type of trail be it Flow, Technical or Free Ride
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In my experience, the current trail ratings are a rough guide at best. There’s no comparison between a double black here in Vic, compared to something like a double black at Maydena.
Maydena seems built around a Canadian standard.
I’ve done very little other mainland interstate racing, so I can’t compare them.
 
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moorey said:
In my experience, the current trail ratings are a rough guide at best. There’s no comparison between a double black here in Vic, compared to something like a double black at Maydena.
Maydena seems built around a Canadian standard.
I’ve done very little other mainland interstate racing, so I can’t compare them.
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Agreed, Maydena seems to have a different scale, one that is probably necessary otherwise most of the hill would be either black or double black, the place is steep!

There is definitely variation between the states from what I have ridden, but even between Derby and Maydena for example, it's probably more about the trail builders as I guess they are the ones that grade the trail at the outset?
 
Sekt said:
https://cyclingbc.net/wp-content/uploads/2014/10/trail_standards_first_edition.pdf
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I like their matrix system for trail compatibility.
One thing that I often find is that Australians don't quite get the fact that Canadian Redwood pine is a hardwood whereas Radiata or similar plantation in Australian Forestry is a softwood and construction requirements/longevity and trail grip differ significantly!
Timber features constructed from softwood are nowhere near as robust.

Another good system I've found is this one from Ireland though they don't use colours
https://www.sportireland.ie/sites/d...4WlcdR41_vYvAKQB27WVmA149dIj45CuE5IkunT5bDyt8

In the UK, they use White - Easiest, Green - Easy, Blue - Intermediate, Red - Advanced, Black - Extreme (and sometimes Orange - Bikepark)

I notice that MTBA have taken their TDRS down and are reviewing it!
 
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