Fixing a hazardous turn in Pt Mugu State Park

On Sunday April 15, as part of National Volunteer Week, about 40 Amgen volunteers gathered in Pt Mugu State Park to work on the Sin Nombre Trail. Most of them worked on fixing ruts and cutting back overgrowing brush, but 8 of us, all but one mountain bikers, split off to fix up the dangerous corner near the top of the trail at Ranch Center Road.

The problem is at a dip to cross a very small stream, combined with a tight left turn.  After slowing to negotiate the turn at the stream crossing, the rider encounters a short but unexpectedly steep climb out of the stream. Because the trail has been downhill until this point, often people are in too high a gear and stall trying to climb the hill. When they put their foot down, they discover that the trail is also narrower than expected and there is little room for their foot, and they can fall about 6′ down the steep bank to the rocks of the stream. The problem is made worse by a rock near the middle of the trail at the start of the climb out that it high enough to bang your pedal on. Many riders have fallen at this turn; some were taken out by helicopter with serious injuries.

We widened the trail and fortified the outside edge with large rocks. Gaps were filled with smaller rocks, then everything was covered with dirt.

On Sunday, I enlisted a very experienced trailwork volunteer and crew leader for the Santa Monica Mountains Trails Council to figure out what we could do to cut down on the number of accidents on that corner. His solution was to build up the outside edge of the trail with large rocks to make it a little wider, and to remove the protruding rock at the start of the climb out of the dip. So after a lot of digging and relocating really big rocks, the trail is almost a foot wider, all of it on the outside, so there’s more room to put your foot down if you stall out on the climb out. The rocks also armour the outside edge of the trail so it’s less susceptible to errosion and so will last longer.

As we were working, a large number of mountain bikers rode through, the vast majority of them thanked us for fixing up the trail. Some of them told us of stories of having fallen at the corner and injuring themselves. None of them appeared to be beginners.

One fellow fell in and hit his neck. He couldn’t move, being paralyzed in all his limbs and with no feeling in them. That lasted for what must have been for him the longest 10 minutes in his life, before feeling started to come back and he could move again. It turns out he’d sprained his neck. Talk about a close call!

Another rider said he tore his shoulder and broke his collarbone when he fell there.

We believe the trail is safer after our work, but it is still risky to people who are taken by surprise by the steepness of the climb. The trail is wider so it’s easier to put your foot down on the trail, but if you’re riding too close to the edge, you can still go down the bank. So always be careful on this corner, and advise less experienced riders to get off their bikes and walk!

You can see photos of the work on the photo gallery.

4 Responses to “Fixing a hazardous turn in Pt Mugu State Park”

  1. Julian says:

    We appreciate the work done on that turn. The MBU has had more than a few medicals due to that turn. Now we can clean it on our tandem.

    However, much of the rest of the work done on Sin Nombre has turned that section of trail into a freeway. The speed bumps Mother Nature had placed (aka ruts) have been removed and the resulting trail is very, very fast. There have been issues with some MTBers riding that section of trail as if it were a one-way DH trail, and the trailwork only makes this issue worse. If you’re riding north on Sin Nombre, you need to be on a constant, vigilant watch for singles and groups headed downhill at speed.

    Normally this wouldn’t be as much of an issue since a few rains will help bring back speed-reducing features, but rain is pretty much over for the season, so this trail will be fast through summer, at least.

    • Steve Clark says:

      Julian, The work that was done on April 15th did not complete the needs for that trail. You have identified the problem – visibility of approaching trail users, or lack thereof. This past Sunday, as part of the Santa Monica Mountains Trail Days, we trimmed back the bushes next to the trail to improve the visibility. We paid special attention to the bushes on the lower (steeper) section of the trail that were on the inside of curves and blocked the view around the curve. We also did some treadwork to fix a couple of other issues. You can read about it here:

      Also remember that the trails are for all users, not just mountain bikers. While ruts may slow some bikers, they are disliked by hikers because it’s hard on the knees and ankles to walk on a trail where the tread is V-shaped.

      If speeding bikers continues to be a problem, it may be necessary to install pinch points to slow them down, like the ones that have been installed on Tapia Spur Trail in Malibu Creek State Park.

      – Steve

  2. Julian says:

    Steve, thank you for your reply.

    We’ll be sampling the new trailwork done with a ride this afternoon!

    I am totally on board with the idea that the trails are multi-use. However Sin Nombre and Two Foxes are primarily (95%, at least) used by mountain bikers. There’s various reasons for that, but I’m not sure smoothing the trailbed out is going to help bring hikers to the trail, primarily due to the increased speeds.

    If something is done about the increased speeds, I would hope to avoid the issues that the rocks on Tapia have presented for mountain bikers. Particularly because, with a tandem, navigating a pinch point is much more of an issue…and the original incarnation of the Tapia rocks wasn’t rideable by single riders much more advanced than I.

    Thanks again for the work and the reply. Cheers,

    • markmtb says:

      Great discourse, folks! One other point is that trail work and trails in general are dynamic. A newly worked-on trail is always going to look drastically different right after the work, compared to the months or even years it took for the trail to get to the condition it was in prior to the work. Also keep in mind that CORBA does not decide on the work to be done, we only assist. We feel it’s better to give back to the parks through this process than to not work on trails. Thanks again for your support of CORBA and shared use open space trails!

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