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I'm on the other side of South Park from you.  Not really many good options close & easy.  The Yough is relatively close, and able to get use out of your kayak, fly rod and waders.  Local clubs stock trout in the closer areas of the Yough, but you're most likely to get into smallmouth bass now.  I think most of their trout don't survive the Spring stringers and Summer heat, definitely some hold overs.  A further away from town, towards Ohiopyle, the state stocks with trout, and cooler waters help keep them year round.
 
Chartiers Creek is even closer, but water quality isn't the best.  It's kind of urban/suburban for most of it.  There are nice stretches in USC, that are relatively undeveloped.  Again, mostly warm water species.  Not really big enough for kayak.
 
Slippery Rock Creek is nice, it's used for white water kayakers, so not really advised to fish from kayak, unless you know the creek.  Can wade and catch trout & smallmouth.  Unless you take a vacation day or fish on the weekend, it really isn't an "easy" place to go, if you are looking to get out for an hour or two after work.  Getting there after work would likely take you two hours, an hour during weekend/off traffic hours.
 
Nashannock Creek is less than 1/2 hour past Slippery Rock Creek, and has a nice fly fish only section.
 
Other more local places are Cannonsburg Lake (also kind of nasty, but stocked with trout) and Peter's Township Park which isn't stocked with trout, but much nicer atmosphere (less trash floating around and doesn't have as much sediment smell).  Can take your kayak out and might see 1-2 other fishermen.  Will see 50 joggers or hikers.
 
You always have the Mon too.  A ton of fish, but not very clean. 
 
Personally, I mostly fish Lake Arthur now days.  I boat fish 90% of the time.  Good wading now for largemouth and panfish and definitely a good lake to kayak.  The panfish seem to be more interested in meat right now, but definitely can be had on the right streamers.  I do pretty well on a bluegill fry immitation when they are really active, but quick to spit now.  I fish them under a bobber with spinning gear, since my boat has too many hang up spots for my fly casting skills.  With waders, you have a good bit of room to get the flyrod out.  Just be careful wading back in the cove areas, there are some soft spots that you can drop down knee deep.  Most of the main lake is pretty rocky though and relatively easy to wade.
 
Basically, anything worth while is an hour drive without traffic.  Most places aren't worth even trying to get to after work (especially when getting dark at 7PM).