Re: Makara Peak Trailwork: Death Drain Death

Postby Oli on Fri 17/Dec/10 3:58pm

Owen wrote:
Oli wrote:Who put them there?


They shall remain nameless for the purposes of this thread. Needless to say, the said trail devil/fairy does a heck of allot of other work in the park and has made considerable positive contributions else where. There would not be a much point in lambasting them personally.

Not unauthorised, just not very well thought out.
Fair enough, Owen. Good response, thanks. :)
Oli
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Member for: 14 years 4 months

Re: Makara Peak Trailwork: Death Drain Death

Postby sifter on Fri 17/Dec/10 4:43pm

What is the correct solution to these drains then, just out of interest. Currently, pooled water is being allowed off the tracks by said drains. Is this bad? Should the drains be cut and the cut filled with gravel? Rock? Serious question, since the drains don't bother me nearly as much as puddles do - on the three times per year I ride at Makara Peak... :(
sifter
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Member for: 16 years 1 month

Re: Makara Peak Trailwork: Death Drain Death

Postby Robbie on Fri 17/Dec/10 5:27pm

There are many ways that a track can be drained without cutting a notch into the surface and the edge.

The simplest is a very gentle outslope, so water easily flows off the track. These can be very gradual and basically not noticable. Not fun on corners however, as they make an off camber which steers the front wheel outwards. "camber thrust" on a bike tire is a very significant determinant to where the bike ends up!

Another solution is to place a "roller" (or grade reversal) in the track, where the surface rolls up and down in a gentle wave shape. The low point will then consolidate any water, and be angled to let the water out. The majority of the riding surface can then be built to optimise the riding experience.

A huge advantage of these is that running water will never wash down a track for any distance, so "rivers" will not form on those days when we get 75mm of rain. These rivers wash the soil away. Once this happens it is very very difficult to restore a solid even surface.

Another thing to consider is that if we are able to seperate turns from the low points- we can let the track drain where the turn itself is not compromised by off cambers etc.

Sometimes it is necessary to lift up a whole corner to stop it becoming a bath in the winter. Recently we did just that on Smokin. The alternative is to cut the outer edge of the corner away, which can result in track that is awkward and nasty to ride for beginners and experts alike.

On a track like North Face dozens of these rollers are there to keep speeds relatively even and to allow drainage, and for fun :sly:
Another trick is to ensure that the track drains just before and just after every switchback, to once again reduce the chance of any heavy rain water gaining momentum. Ideally the drains are set away from any useful cambers, so the corner rides nicely and the drains do their job seperately.

We should be able to have SWIGG/Starfish drain properly, the new drains will take longer to make than simple notches, however they should last a long time.

Sometimes it is also a matter of having one proper drain, rather than a few small ones. To make these sometimes only small changes need to be made, with any luck!

A thing to remember is that water always always flows downhill, no matter how small that gradient might be. And that direction might be down up, or across the track.

For those after more techie data, all of these tricks and many more have been documented in the IMBA books and videos, and when taking local clay and rocks into account, work really well. For those who have spent years maintaining existing tracks in wet climates all of this stuff will be very farmiliar !

Me, I am not fussed about being splashed by puddles, however puddles almost always mean the track is getting damaged and being dissolved under the water. This is not good, and time spent repairing that damage is better spent riding, building new tracks, or sitting on the couch!! :lol:
Robbie
Member for: 15 years 3 months

Re: Makara Peak Trailwork: Death Drain Death

Postby sifter on Fri 17/Dec/10 8:55pm

cheers for all that Rob! Though most of it seems to relate better to track design than maintaining existing track. It sounds like the Supporters have a lot of work to coordinate, carefully balancing the tension between enthusiasm for new track and general lack of enthusiasm for maintenance. It might be worth discussing alternative methods with the generous pixies too :thumbsup:
sifter
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Member for: 16 years 1 month

Re: Makara Peak Trailwork: Death Drain Death

Postby Robbie on Fri 17/Dec/10 9:22pm

We have good turn outs for track maintenance, as long as it does not exclusively relate to trimming vegetation.
So often track maintenance is no different to building a new track after it has been cleared and benched: just making sure it will drain well, and that it is packed down and has good solid foundations. If attention is paid to the speed and flow of the track, all these things combine to create sustainability nirvana. :D
We also make it nice to ride whenever we can.
It does all take time.. however we are running more than work party per week these days, and they do run longer than yesteryears, so I am sure we will get there.

:thumbsup:
Robbie
Member for: 15 years 3 months

Re: Makara Peak Trailwork: Death Drain Death

Postby AJK on Sun 19/Dec/10 8:43am

Morning bump.

According to the forecast, this rain is only supposed to be occassional. So you never know, it might be dry up Makara by the time we start (and it's not all that cold and miserable). I'll be there either way, I've got a wedding I need to work off.

SWIGG/Starfish from 10am.
AJK
Member for: 11 years 2 months

Re: Makara Peak Trailwork: Death Drain Death

Postby Robbie on Sun 19/Dec/10 4:30pm

Well that could have been a lot worse :lol:
Robbie
Member for: 15 years 3 months

Re: Makara Peak Trailwork: Death Drain Death

Postby happybaboon on Sun 19/Dec/10 4:40pm

Wasn't too bad. Pretty warm really, just also very wet.

Managed to fit a decent ride in too - Groveled up to the very top. Got super windy, so the wet and windy ride down the first bit of Zacs came with double the meat and extra bacon. Northface was draining very nicely, RLE was a swampy puddly mess. But the white tigers what I gots really thrive in this sort of weather so I didn't lose grip once.

Finished off with a ghetto clothes-on shower with a hose in the carpark :D
happybaboon
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Member for: 17 years 10 months

Re: Makara Peak Trailwork: Death Drain Death

Postby Robbie on Mon 20/Dec/10 3:03pm

Many an evil drain was demolished, reprofiled or moved.
Greenery was tamed.
People got very very wet.
People did not quite get flattened by other people on bikes.
:lol:
Robbie
Member for: 15 years 3 months

Cycling | Lower North Island | Makara Peak | New Zealand | Regions | Trail Building | Wellington | Wellington Region - Latest Posts

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