No Thorald Creek-specific exception appears in the Region 4 tributary review, so regional stream defaults apply: closed Apr 1 to Jun 14, trout and char catch-and-release Nov 1 to Mar 31, and single barbless hook required year-round. Confirm the current synopsis before you fish.

The creek's mouth sits at 50.35030, -116.11657. It runs stream order 4 (mid-range on a scale that runs from 1 for a headwater trickle up to 6 or more for a full river) across a 32-segment channel network, feeding into Brewer Creek before that water reaches Dutch Creek and the Columbia. Brewer Creek itself carries a short but real record, four bull trout, two Dolly Varden and one westslope cutthroat trout, and that is the best available signal for what Thorald Creek might hold, not a confirmed count of its own.

With no direct fish records, there is nothing here to book a day around. If you scout it, the honest expectation is small, cold, steep-gradient water that could hold the same bull trout, Dolly Varden and westslope cutthroat family found immediately downstream on Brewer Creek, but that is an inference from the neighboring water, not a confirmed record for Thorald Creek itself.

Should coldwater fish turn up, a small-stream box covers the likely food base: caddis, mayflies, stoneflies and summer terrestrials. Start with a small Adams or Royal Wulff, move to an Elk Hair Caddis or Stimulator, and fish a Hare's Ear or Pheasant Tail underneath.

No confirmed trailhead, parking area or road-legal access point has turned up for Thorald Creek. Treat it as scout water within the Dutch Creek drainage: check current Forest Service Road status and land tenure on the ground, and expect a walk-in approach typical of small upper Columbia Valley tributaries.