I was going to try for somenative brook and wild brown trout fishing in Sullivan Co. PA but I'm wondering if there is enough water in these area streams for decent fishing? Any help would be great.

should be....just focus on the pockets of deep water and you should do fine!

I'm not from PA but anybrook that has cold water springs in them that will keep the water fairly cold will support brook trout. Up here the fast water rips are still doing good. If you have pools thathave three or four feet of
water will keep trout around as long as it stays cool. These trout were
caught in a foot and a half of water in the rips.