Freeze/Thaw Guidelines for Winter Single-Track MTB & Hiking
by George Pastorino, EBC MTB Coordinator | MTB@ElmhurstBicycling.org | Last updated: 12/15/2023
It's Winter and that means Freeze/Thaw rules go into effect on dirt trails. We all want to ride but we all have to act like adults and be patient and wait until the conditions are right. Once there is a hard freeze, this phenomenon happens: As the temperature drops, moisture in the soil freezes and It's like when when you leave a water-bottle in the freezer, the water expands as it freezes and can crack the bottle. During freezing, soil particles are forced apart by expanding ice crystals which de-compacts the trail bed. When these ice crystals melt as the temperature rises the resulting spaces fill with water and form slushy mud. Trails in this condition have little structural strength to support the weight of riders, hikers or runners.. Waterlogged dirt with of a very thick consistency results. Also, remember that dirt thaws out much quicker than snow or ice as darker objects absorb heat much better than light colored objects.
Rule 1
There is only one rule and that is if you leave a tire, foot or hoof print, stay off the single track. There are no exceptions to this rule and no one is so special that they can ride/run/hike on dirt trails whenever they want, no matter the conditions. Doing that is just plain selfish. It doesn't matter if it took you an hour to get to the trails. If the trails are wet or soft, stay off. Today’s ride is not as important as being responsible and not damaging the trails..
Tip #1
If the weather is going be above 25F degrees/sunny or 28 degrees/Overcast for the time frame of your ride, stay home or ride limestone or pavement
Tip #2
If the weather is going down to around 20F the night before your ride, get out early. If you get on the trails by 7AM or so, you should be able to get in a good ride before the sun heats things up. Once the sun hits the trails everything will begin to soften up. Always be off the trail by 10AM at the latest.
Tip #3
The best Winter single track riding & hiking occur when the high temp is below 25 and it is overcast. Ideally the colder night time temperatures will have frozen the trail solid and the lack of direct sunlight will allow you to ride until 10AM. Of course if it's zero degrees, you can ride later. Park on the North side trails, then ride over to ride the South facing trails first and finish back on the North Side. The sun thaws South facing trails first and North facing trails generally have a good 30-60 minutes of additional time for riding/hiking/running time before the thaw.
Tip #4
Alternative places to ride - Limestone multi track trails are open year round for the most part, shed the water better than dirt surface trails and are not as easily damaged. The multi track at Swallow Cliff and Cap Sauer has some good hills that will make things interesting. You can string together a pretty long route with more hill climbing than you find at Palos. Waterfall Glen is another option, though not as fun nor as hilly as Swallow Cliff. If it is really wet, then pavement is your best choice.