AB, B.C and Mt. in early September

My wife and I had been scheduled to fly in Calgary on June 29th to ride a modified TD route down to WhiteFish Mt. A few weeks back, she took a mis-step and had a non detached fracture of the lower fibula. So... no riding for several weeks. That caused us to cancel flights, hotel reservations and scrap the trip.

I fly somewhat regularly and never get insurance. Sure enough, the tickets that I booked were non refundable. But, in the case of injuries and illnesses, they are covered on a case by case basis. They can be rebooked though; however, there is a $200.00 per ticket fee applied unless it was due to an injury or illness.

So...

I am working with the airline to rebook for the last week of August and be in the mountains late August and early September.
In years prior, I've been up there in early to mid June right after the grand depart. Water was plentiful as was the mud.
Last year, I rode with my son and a coworker in mid July. It was hot, dusty and snow melt runoff was a little more hit and miss.

What is water like out in the mountains in September? I'd assume that snow melt is mostly gone by then. The areas where I could see the biggest issue is from Fernie down the Wigwam road to Galton pass and possibly heading over Whitefish Divide.