In the process of fixing up a local DH track. What was once an enjoyable beginner friendly track that had nearly 100 racers has become a rutted, rocky horrible mess that no-one wants to ride.
One of the major priorities is to first fix the drainage. Being quickly constructed in the beginning the track does not use the slope well and often follows fall lines causing water to pool.
Will post pics of progress as it goes. However happy to take some feedback and advice on how to fix each section up as pictures are posted. Firstly what's the best approach to fixing the following drainage issues as you can see the below result after around 16mm of rain over 3-4 days. Being a DH track the berms and braking ruts are filling with water.
View attachment 241150The water is running along the trail, eroding between the rocks and probably pooling in the berm. Slope is right to left. First make a drain before the berm diagonally from the uphill right side to downhill left side of the trail. Make it wide and shallow enough (a reverse grade rather than a drain) and far enough from the point riders will reach maximum lean that it is a fun entry into the berm rather than a threat. It must get all water coming down the trail off even in a deluge. You have huge rocks. With luck the drain/reverse grade can be started by removing a line of them and then shallowing everything out. In the pic you can see a few in the immediate foreground that fit the bill. They are probably too close to the berm to use though. Consider a drain that is narrower on the upslope and wider as it gets more downslope. It's easier to keep it shallow and even. After we shape the soil in the drain we add 5-20cm stones, lots of them and hammer them into the ground. Going back after the next rain and adding more helps. You will be able to harvest them on and near the trail. We use a sledgehammer and a major league tamping tool called Richter that weighs 8kg+ to achieve an armoured surface in the drain. Excellent grip for tyres and water sheets over the surface easily.
Next dig out the inside of the berm and save all the rocks. Be generous and dig fairly deep and wide so that you make a new berm out of solid base. Use the excavated rocks and soil to rebuild the rim of the new berm by adding fill over the existing large rocks. This will end up higher than the riding line, but you need that for riders to feel secure. It will shrink a lot so be generous and tamp a lot as well. Try to save all the grasses so they can grow through the back of the new berm and help stabilise it more (this little berm is not the best example of saving vegetation). Also try to harvest out stones the size you can use for that drain (so doing this bit "next" is relative). What you want is a new deeper berm using base - same radius, just a little more uphill. Yes they'll say it will pool more water, but that's wrong if your pre-berm drain works, you make sure the berm continues to go downhill and you also make water drain off immediately after the berm ends via another drain as above. Riders will exit the new berm upslope of the old one allowing you to make that drain away from the new riding line.
View attachment 241151Right to left slope. You have a serious rock garden in the midground. Try to make 2 lines through it. Faster line to lookers left and beginner line to lookers right. The beginner line can be smoothed with smaller rocks and maybe some soil. Aim to exit both lines to the upslope (lookers right). Outslope the entire area from the rock garden to the foreground. When you expose rocks doing this, do not remove them, but hammer them back into the base. It will harden the trail and should always be the preferred way to manage exposed stones including in berms. Removing stones where tyres and water flow always leads to more exposed stones and ruts. Armouring the surface with stone as above, especially on the upslope side of the trail will provide more durability. Water should sheet off with riders being upslope of the current line and a new rut should not form. Trim back the vegetation to encourage riders to see the new line: eg the thin stuff up to 2m wide of the trail in the right foreground of the pic as well as the stuff upslope before the rock garden. That will change the trail from a straight line to right left right swerves with the rights being drainages and the left being a rock garden highpoint. You can choose to save the big downslope edge rocks in the foreground as visual clues too. Uptrail of the rock garden you could use an anti-IMBA technique and place a large log lookers left of the trail and fill small stone in to the log to create an elevated trail. If you can maintain a gentle outslope it definitely will accumulate water and silt. Sounds bad, but it will harden over time, add a visual clue to the line into the rock garden if placed well and as it leads to a high point, after it hardens water will flow along the log back to the nearest dip in the grade (ie before the log). Never use this technique over soft ground like in the next pic. It only works on rocky tread.
View attachment 241152Right to left slope. Create a long and gentle reverse grade right through this section with significant outslope. Widen the trail a little to encourage a slightly upslope line and again armour the surface with small hammered-in stone as above. You may have to create a more seriously armoured drain in the middle where it looks like surface water flows fast. Here the trail changes from a right left right swerve to a longer gentle right bend with a gentle reverse grade in it.
View attachment 241154Right to left slope. Not an easy pic to interpret. Start by creating a big diagonal reverse grade drain in the wettest area near all the stones before the stringybark gums in the midground and severely tamp the "berm" so water can flow past it and drain off lookers left before the jump where you will probably have to make a new reverse grade drain. After that watch and see what happens. This bit looks like it is coping OK.
View attachment 241153Slam the left surface down to create a long right to left outslope and get the water off the trail by sheeting it before it reaches the jump. I'll post a pic of Richter at the end.
View attachment 241155I am guessing you have to turn this into an armoured berm, but the radius is all over the place and the sapling and general vegetation makes that line hard to see from the pic.
This is a separate challenging section it's a steep straight run down some rock slabs into a slight right turn. There's a huge rock in the middle meaning the water and riders are forced left or right. Easiest option is to take the low side which has created a stall point. Idea is to pretty much remove all the rocks bench it out into a small rolling crown style turn or maybe a small hip berm. Will see what happens when we start smoothing. Photo's don't do them justice but the rocks are around 50+ kgs each.
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