The 2018 Dirty Dash, scheduled for September 8th in Missoula, has been cancelled due to low ticket sales.

Dirty Dash on Facebook

I have to wonder if the lack of participation is due to marketing issues. The event came to my attention once at the start of 2018 and I haven't seen, nor heard, anything about it since. Perhaps if more people knew about the event, they would have purchased tickets? Just my thought, other comments on the post indicate that the ticket price was too high. Either way, the muddy run is a no-go for this year. As you can see in their post, refunds will be direct deposited within 10 business days from today.