Rain and Trail Riding in the San Gabriel Mountains

Brown Mtn saddle gets muddy after a good rain. Tread lightly.
Brown Mtn saddle gets muddy after a good rain. Tread lightly.

Over the last several years of drought in Southern California, you may have forgotten the riding etiquette after a rain.

Or you may be new to mountain biking and didn’t even realize there was an etiquette to riding during or after a rain storm. The answer can get a bit complicated because if you want a precise answer for the particular trail you like to ride, there are many things to take into consideration such as:

  • Soil make-up (clay vs sand/rock ratio)
  • How dry the trail was before it rained
  • How many inches of rain it received
  • Humidity level after the rain
  • Trail location and drainage grading
  • How much sun/shade it receives
  • Etc.

All important factors to consider and if I were a math nerd, I’d whip up an algorithm that would input all this data and spit out how long you should wait, down to the minute. Just kidding. If I were a math nerd, I’d be working for the Mark Zuckerberg, hopefully on my way to becoming a gazillionaire so I can buy more bikes.

trails and rain
BAD!! Plus, how is this fun??

As a general rule of thumb, wait a few days after it rains before riding your local trail.

Especially wait to ride trails with high clay content including a large part of the Santa Monica Mountains, and in Santa Clarita (Viper trail comes to mind). These trails are full of clay, and get super muddy and sticky when wet. If you ride those trails during or immediately after it rains, your tires or shoes will strip off the wet part of the trail and you and your bike will be a gross, muddy, sticky mess. The trail will be significantly damaged, and we will all hate you.

Please wait until the trail dries up. We will thank you, your bike will thank you, your car floor mats will thank you, and your washer will thank you.

For our San Gabriels, the above bulleted points are still factors, HOWEVER, because the San Gabriel Mountains are comprised mainly of decomposed granite and sand, along with a generous heapingful of horse poop, we don’t experience the same kind of trail damage and erosion from riding after it rains.

What does this mean for you? It means you can ride our local trails (San Gabriel Mountains) shortly after a rain. However, don’t be THAT GUY/THAT GIRL.

Watershed trails like El Prieto and Winter Creek in Chantry Flats get very wet after heavy rains and should be avoided for at least a day.

Use your head. Not to break your fall, but use the stuff inside it; employ common sense, people!


If it’s been pouring buckets of rain, wait a few days before riding our trails. They can still sustain damage; our trails are made out of rock, dirt and poop, not steel.

Additionally, exercise caution when riding after a rain or a wind storm. You may know the trail well, but don’t let the dislodged rock, fallen tree or landslide on the trail take you by surprise. Be aware that our trails are constantly shifting and rarely remain the same after a storm.

And lastly, if you see trail damage, WHO YOU GONNA CALL??? That’s right. MWBA!

(well actually, an email is better, [email protected], or a post on our Facebook page www.facebook.com/groups/MWBAorg. you get the idea…)