How to pull up front carpet (driver's side)?

Greetings all!

I was changing out the floor mats (carpet to all-weather) and discovered that the carpet in the driver's footwell is wet. When I push down on it in a couple of places I can hear it squish, so I obviously need to pull it up and dry out the area. Does anyone know/have a link for how to do this?

Also, my guess is that this is due to either a blocked A/C drain or the cowl drains -- any other suggestions?

Thanks in advance!