When a vacation starts getting past 8 days, I think it starts to make sense to pack only enough clothing for half the trip and plan to spend a few hours at a laundromat.
A few hours in the laundromat is really boring, I admit! But it beats lugging 2 suitcases through the airport.
And it is good to have downtime on a fast-paced sightseeing and hiking vacation. It is a chance to catch up on reading and planning your next day.
In Jasper and Banff townsites, doing laundry is not a problem as there are multiple places to get rid of the dirty laundry stench cloud wafting from your suitcase.
Some of the smaller hubs, like Lake Louise, lack public laundromats. If that happens, another option is your hotel. Some hotels will have a coin-op laundry area.
Another tip is to skip the dryer and hang wrenched wet clothing from hotel room bathroom fixtures and anywhere you can find in the hotel room. This I do often.
If you want to get all Rick Steves, skip the laundromat altogether and wash laundry in the bathroom sink. I’ve tried this a few times. Let’s just say that it works but takes some getting used to. I trust the washing to do a better job.