MTB Trailcare

A bit late, but losing internet for a few days is a small price after last weekend's disasterous weather.  Best wishes for those doing less well.

Yes, there was trailwork over the weekend.  Let's be clear, being out in the bush in wild weather is not recommended and as you would have heard many times this week, putting yourself at risk inconveniences and may endanger others obliged to help.  Ashley and I did not do what we did lightly.  After many years spending wet days working to save trails, we planned our actions to avoid the worst weather, to be sheltered from high winds by the lay of the land and there was never a time when our eyes were not scanning above for potential danger.  

Trailcare is not a fair weather activity.  If you don't see what happens in the rain, then you cannot make appropriate trailcare decisions.  In case you forgot over the last 9 months, it usually rains plenty here.  While a lot of riders on the coast couldn't give a rat's about their influence on the trails, the effects of single tyre ruts, the accentuation of runnels and damage to new trailworks, someone has to. Ashley posted his opinion about riding in the wet on mtbdirt and I cross-posted it to rotorburn today, but if you are reading this you probably already get it.  

Our aims were to assess recent trailworks and to attend to a trail emergency.  More of that soon.  On Sunday morning, before the wind peaked, we did a trail inspection of recent work on Casuarina and Pete's.  We were pretty happy with what we saw, but knowing the 50-60mm or so that had fallen was on dust (or freshly turned dust and rock), we had and have concerns about the ability of all trails to survive what just happened.  There has been a lot of wind damage; we know that, but have yet to check most trails.

Sorry about the raindrops on the lens.  I used an umbrella over the camera (trail-dork alert), but it was pretty windy and wet.

Starting on Casuarina from the North Street Fire Road side, here are some pics.  First a section below the new intersection with Pete's.  This was all renovated recently as covered in previous posts.  Water was sheeting and draining well, the new berm and exit to the older trail were sound

Casuarina Loop has so many isues, but some can be sorted as shown above.  Some of it though, is beyond help.  After many years of salvage work, the fact is that parts of Casuarina will never be good trail.  The first bit next to the velodrome is worth saving - as a drain!!   It was flowing like a river and the best you can say of it is that it stops some water getting from the fire road to the bush nearby.  Thank you to Aaron, who was out in the rain trying to save this bit of trail by constructing little water bars on the trail and trying to divert fire road drains away from the trail.  We would like to hear from you.  You have a good heart, but without a bulldozer or time to close and re-route it, you cannot save that bit of trail.  We can help you learn how to work on trails and keep Nerang intact.

QPWS expects us to build trail to a standard and if we do not do it, there will be issues.  While we care a lot what QPWS thinks, we care even more that a failure to build sound trail penalises riders and trailcare workers .  

Here's a new section of Pete's Trail, starting with a bit that should never have been built, even if it looked like a good idea at the time  

Killing trail flow to put in a bog-hole complete with a semi-concealed rock on the downhill entrance, ignoring all rules of trailbuilding by just kicking stones to the downslope edge (at least they weren't sticks!), rather than putting in the effort to appropriately route and drain the trail is not acceptable.  Now we have two options:  go back every time it rains, find and compress stones into the mud until it becomes an armoured high point, or rip it apart and find a better trail line - like that is possible now on an open trail with all alternate line options removed in the original design.  Not happy Jan....

Here's a pic from the same bit of trail.  It's not hard to get it right in the first place and doing so saves endless, unnecessary hours of volunteer repair work

A few mm of puddle held back by leaves will over flow and flush with heavier rain.  We can live with that

We were keen to assess the bit of Pete's yet to open.  It will be a few more days before any tamping can be done here, but all was looking good apart from wind damage and some of our old (failed) trail closure debris

You can see water sheeting gently over the trail in previous pics.  In the next you cannot see the water running through the stones on the inside of this turn, but it was.  After time the stones will silt over, but remain an inslope drain leading to an exit for the water

Even the last bit of trail to be built was coping with the water, but looking bad from our closure debris.  Compared to the fire road, drainage was good.  You should have seen the fire roads when the heavy rain was falling!

Over the road we checked recent changes and were happy with them up till the really big rains and wind stared.  Then we took off for a safer side of the hill

It's not all about new trailwork.  We keep asking people if they would like to take stewardship over a trail they love, after it is restored to QPWS standard.  People are scared it means endless hours in the bush, not riding.  The next two pics show what normal trailcare usually means.  

We believe a 2km section of trail would require about a half-day of trimming and preening every three months, allowing for weather catastrophes requiring the help of other volunteers.  And yes, the gumboot scratch removed all water in this puddle blocked by organic debris.  No puddle = dries faster = less damage caused by riders out before the trails dry enough to be ridden.....  The other gumboot pic is a simple test of the stability of the trail edge after recent work

It is nice to see water sheeting off the trail, or flowing along inslope drains and then sheeting to drains

In the next pic the puddle in the background is due to runoff from the fire road, just out of view.  It is fixable with a reverse grade closer to the fire road

Drainage solutions are usually pretty simple.  People site sections of trail they love and don't want changed, but they fail to see trail cupping and are not there to see what happens in the wet.  A couple of rolling grade dips would solve what you see in the next pic and make the riding more fun as well

The next pics are of work done in the last few weeks.  Falline erosion was remedied with drains before and after a couple of turns.  Those turns now subtly bermed with water running on the inslope and the riding line away from it.  It was all solid

We don't know if the rut in the next pic was made by MTB riders, a moto, or just someone doing their year's-worth of trailcare, but it did show that, despite all logic, the best drain from this berm is on the uphill end.  Ash dug out the end-of-berm roller and all the water drained "uphill" into the foreground drain.  We will probably change this drain a little more soon, by increasing the depth and using the stone to embed and armour the puddle area

Now some pics of the latest work on Pete's upper trail.  At the rangers' request, we re-routed this as per recent trail news.  While there is substantial water on the old trail line, it is either puddled, or moving slowly through closure debris and soil bars.  On the new trail, things were solid and draining well

After the inspection we went back to work on Barney's Trail.  In recent communications with QPWS, we asked permission to attend to trail "emergencies" out of order of the trail priority list and they said yes.  Weather issues were the main concern.  It was pretty obvious we were in for a drowning over the Oz Day weekend and that it could be the end of the big berm at the top of Barney's.

The berm has been great fun to ride, but after considerable pleasure, at last four other 200mm rainfalls and the better part of 9 months of drought, the surface has been scoured away from rocks in the wall and the huge, stone drain has clogged with many cubic metres of eroded dust.  As new, it looked like this

I don't have any pics of it flooded, mainly because it used to drain immediately. When it did start to block, it was very temporary and the rain required to overflow it was too heavy for pics.  This weekend, working on it was the priority, but there is photographic bath-ring evidence from a previous rainfall

When the drain first started to block with sediment, it was just a matter of lifting the top stones and it would pour out like a whirlpool.  Alas, as time went on, the drainage was more sluggish and overflow was damaging the integrity of the lower wall.  In addition, all the dirt that blocked it had been removed from the wall by tyre erosion and the riding line was becoming less comfortable.

What was needed was better drainage and refurbishment of the riding surface.  First we closed the trail with signs at the entrances and tape

If you are going to dig a new drain, then why get rid of the fill.  We separated the clay from the rest and backfilled the wall of the berm.  Looking at the top entrance to the berm, the large, exposed rocks would have to wait until after the drain was completed

We excavated the trail past the berm and lowered the exit from the berm , as well as wideing the exit line.  This allowed us space to build a substantial rolling grade dip (really an enhanced reverse grade) almost level with the original exit of the berm, improve inslope drainage, construct a wider and more reassuring line out of the berm and lots of fill was left over for the berm wall and resurfacing the riding line.  Here are some pics from Saturday

and some from Sunday after we removed or re-embedded rock on the riding surface, further modified the drainage and re-surfaced it with clay.  

Despite the very heavy rain, eveything was bone dry a couple of cm below the surface of the trail and berm and we had to collect water to damp things down before hand compacting a mix of pre-worked clay and soil into the gaps to prevent it all peeling off.  We know some did not survive the torrential rain and wind of late Sunday and Monday, but the surface was still good this afternoon when Ashley went in to check after work.

It looks really muddy and nasty, but that was coming from what we plastered on, the effect of lots of gumboot action on the inslope and the fact it was fair-dinkum pi$$ing it down with rain all day.  It was a good job we think and had we not done it, the back wall of the berm would have washed away and the whole thing collapsed.  Not what Barney wanted for Australia Day.  Best thing is it will ride better and still has that weird thrill of climbing up to the creek crosing after the berm. 

Don't even think of riding there for another week unless you want to destroy it and break our hearts.