That’s close to Mill Ck, trib to the Schuylkill, a PFBC stocked stream. This is the second time in a few yrs that I have heard of mid to late summer catches of RT from that general area. Mill is not a cold stream, so it is likely that there is a spring or group of spring seeps out in the river below Hamburg that the RT are able to find as the river warms. The Schuylkill gets very warm in that general stretch and otherwise would not allow trout to survive the summer. In addition to the Mill Ck source, Kaercher Ck enters the river in Hamburg and would be an avenue for escaped RT from PFBC stocked Kaercher Ck Dam to reach the Schuylkill in the area that you describe.
Likewise, mid to late simmer reports of RT from SMB anglers in the Schuylkill at and just below Reading are somewhat common. There you have the localized cooling influences of Wyomissing and Angelica Cks as well as possibly some springs in the river channel associated with the limestone geology. Those fish probably come from the Tully DH area and other stocked section. Upstream from there by about 7 mi or so is a spring near Cross Keys that also attracts RT to the river’s edge where there is a crack in the riparian limestone formation.
Finally, in the past 5 yrs or so, adult RT have become somewhat common in reports from Blue Marsh Lk as well as an occasional one seen in trap nets set for muskellunge. These fish have silvery coloration like lake fish and perfect or near perfect fins. This is suggestive of some holdover in Blue Marsh with fish originating from its numerous stocked tribs. The problem in interpreting what is occurring there , however, is that Blue Marsh has been around since 1979, stocking has diminished in numbers since that time, but this phenomenon is fairly recent. Yes, trout were seen in the past in the lake, but based on color, timing, and fin wear they were always recently stocked fish except for the occasional wild tiger trout fingerling from Northkill Ck, a Blue Marsh trib.
