A big weekend with Pebbles and Bam Bam

Sunday, 30-Mar 2014 @ 9:54pm

After starting work on a section of Happy Valley last week and not completing the job, 150mm of rain this week, including 100mm from Friday to 8AM Saturday only added to our concern to finish it off this weekend.  However, that 100mm fall on Friday offered us the first chance in a year to stabilise the wettest sections of Pete's Extension and a bit of Casuarina with the gravel QPWS supplied last Winter, so that's where we went on Saturday.  It was the start of a perfect groin rash of a weekend:  really humid, hot and dirty.

So here's how Saturday went, starting from the top of Pete's Extension.  The lowest part of Pete's original trail was looking great only a few hours after the rain ceased

Our log skinny was looking good from above, but things had changed from below.  It looks kinda cool, but this is a pretty dodgy construction and represents one of our issues with QPWS standards.  If they cannot give us the go-ahead to build skinny features, then someone else will and not to the standard they or we want 

In this case an endangered species of micro-koala has had its habitat built over.  Poor little bugger

Regardless, this skinny was meant to end with a drop.  It was designed for challenge and now it has had that taken away by someone who contributed nothing to building the trail with us.  Thanks for that.  We love it when people break the golden rule of trailwork:  Do not change what you did not make!  Help with clearing drains, cleaning up fallen timber, trimming sight lines etc are appreciated, but if you have time to construct, then you have time to help with authorised trailwork!  How about we turn up at your house and change your garden and driveway to suit ourselves.............

Anyway, the log skinny still allows for multiple options, so we left the additions with just a bit of trimming and shoring-up.  Fun is important and until this becomes just a pile of rubbish, people will have fun with it and we are prepared to see things from alternate points of view to our own

Most of Pete's Extension was a lot better than we thought after the rain, so only minor maintenance was needed to drains down to the old Downhill Trail.  Riders will like new line options through the rocky first U turn.

The next pics show what happens when someone thinks a drain drains better when it is dammed with rocks!  Guess what, it becomes a dam, not only failing to drain water from a vulnerable trail surface, but backing it up for even more soddenness!  Let us say this again:  There is no such thing as a rock drain.  There is either rock armouring (of many kinds) or an outsloped drain capable of draining with the help of gravity.  So out went the rocks and the refreshed drain spawned along the outsloped original trail for better effect

The next spot remains a concern.  It was really boggy immediately after the trail was opened (prematurely in our opinion) and riders en-masse chose to ride massive wheel ruts (15cm deep) below the sodden trail, creating a bigger bog during the massive rains of last Summer.  A lovely flowing corner was turned into a boring straight line we still have to fix - also thanks.  Quite a number of those ruts were made by people who tore down and rode over substantial fluoro safety fencing we installed attempting to prevent this happening - double thanks. 

However, we were totally surprised by how stable the trails were after our first big rain for a year.  In places where we planned to embed gravel into mush, the tread was not wet enough to do so effectively and this was one of those places.  An alternative plan to enhance the outslope into a wide drain and add new corrals was considered and rejected

It would work, but increased cornering speed through this section would impact on work started on the next corner where we did embed gravel.  When you embed gravel or stone into soft tread, the tread gets mushier as you tamp it in and stays that way for a while.  To overcome the mush in the short term, you have to add more gravel and it becomes both a slippery and vulnerable surface for a while.  Best to leave the straight line entry into this corner for a while longer

After working with Pebbles and heading farther down trail, it was time for Bam Bam!  On narrow singletrack, durability depends on how riders deal with minor surface features and the lines those options create.  Where outslope is limited by a gentle gradient and weak soil, it makes sense to periodically smash protruding stones back into the tread to allow riders a clean palette, so that's what we did, with a sledge hammer.  The direct sun and humdity were a killer but it came out well

At the next U turn we removed 2 rocks only.  They will not be missed

Below that we did basic drain enhancement until the next rock garden.  No, we didn't flatten the rock garden, because that's what it is, stable rocks everywhere with all sorts of riding lines.  We did change the boggy dip after it though, by adding gravel to the bog


This allows better flow through to the next tight turn

A little more drainage enhancement and we were on Casuarina

This section of Casuarina has never been quite right despite ambitious drains being added during the heavy rains of last year.  A mixture of drain enhancement and embedded gravel was needed.  It will require review soon as the gravel will not stop wheel ruts forming until most of the current water drains away.  Adding gravel is always a multi-stage operation

So that was Saturday.  Sunday was for completion of the work we started on Happy Valley last weekend.  We expected the worst after such heavy rain on work in it's infancy, but we were surprised again.  While you can see runnels where water was flowing off flat terrain near the trail, the trail itself is coping well.  Yippee

This is what we found this morning from top down.  The drains are working well and we hope the organic matter in and over the reclaimed, old trail line will revegetate the area quickly

It's nice looking at what you did, but it does not get what you need to get done, done.  This was our objective today; a deep trench that concentrates both wheel and water erosion down the falline into an inadequate drain.  Previous quick fixes have failed and the march of rubber and time has taken a toll.  It has become a sad place on a fun trail

The first task was to make a wide and gentle drain above the area to make sure water no longer runs along the trail.  This drain lines up with one farther up the trail to carry all water off the trail.  

The rocks collected and placed in the old erosion gully were not meant to be covered over.  That was just an unavoidable consequence of building the new trail line.  They will probably show their face again after more rain and become a visible, armoured drain below the tread.  Most of our diggings and excavated vegetation were loosely piled off the trail to enhance the drain, but some became a water bar designed to cut off the old trail line.  We hope to see all of it sprout new plants soon

This is how it ended up.  Due to poor light (it was raining), you cannot see the subtle grade changes that we hope will get all water off the trail or into the now massive, lower drain without damaging the new tread.  It is still a bit of a lottery as the soil through here is deep organic black on clay.  A bad combination in the short term, but it has great potential in the long run and we will be back to sort out cupping and other issues that come along in the next few weeks

Before we left an animal trail complete with fresh kangaroo poo led us down to this spot.  Animals have some nice places to hang out in the park

Here's to great riding and good groin balm!

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