In this report
28 CFS: Still Small-Water Responsive, But Watch the Afternoon Squeeze
The South Platte above Spinney is running 28 CFS right now—solidly above the natural low-water baseline of around 15 that defines this headwater’s normal operating range. That’s good news for wading access and water temperature stability in a week when early-summer afternoon heat can start to squeeze a freestone stream. But don’t mistake the number for a big-water ideal. This is still a small, open-meadow creek where every cubic foot matters in terms of fish visibility and behavior. At 28, you’ve got enough current to cover ground and keep the water cool enough that trout aren’t retreating into the deepest slots by 2 p.m.—but you’re not swimming in it either. This is the flow window where the Badger Basin and Tomahawk meadows actually work as trout water, provided you fish smart.
Pale Morning Duns Are the Story—and the Challenge
The marquee hatch right now is the Pale Morning Dun emergence, the #16–18 mayfly that defines late spring and early summer on Colorado freestone and tailwater alike. On the South Platte above Spinney, PMDs typically emerge late morning into early afternoon, and this is where the open-meadow character of this water becomes both gift and curse. The emergence window is real—you’ll see flies in the air and trout starting to look up—but the fish here are wary in a way that tailwater trout, with their dam-smoothed predictability, rarely are. In open water with minimal cover and nowhere to hide, a trout feeding on the surface is visible from a mile away, and it knows it. The moment your shadow falls across the water or your fly line unfurls with a sloppy stroke, the fish ducks.
Fish emergers instead of duns. A #18 PMD emerger—think a slightly duller, half-submerged profile—fished in the film or just below will take more fish than a high-floating dry in this water. The emerger mimics the vulnerable stage, and more importantly, it gives you a reason to fish the subsurface window where these trout spend 90 percent of their time anyway. Expect the bulk of the hatch to push into the first half of the afternoon; by 3 p.m., the emergence thins out and water temperature starts to dominate fish behavior.
The Rig: Small, Restrained, and Purposeful
Here’s what works in the meadow water this week:
Point fly: A #18 PMD nymph—something sparse and dark, like a pheasant-tail or a thin Barr’s-style emerger—tied to 5X tippet. This is your anchor, and it should be small enough to feel natural in thin water but heavy enough to hold the bottom in the modest current you’re working.
Dropper: 18 to 20 inches up, tie in a #20 midge (Black Beauty or Mercury works fine) on 6X. The dropper rides in the film or just subsurface, and it’s the fly that often produces the takes. Midges are the year-round bread-and-butter on this water; don’t overlook them for the headline hatch.
Weight and split-shot: One small shot pinched 8 inches above the point fly is enough—this isn’t deep water. You’re looking to keep the rig ticking the bottom of the shallower runs and the transition zones where trout hold. Split-shot placement matters here because the water is thin and sensitive; a heavy rig spooks fish as easily as a poor cast.
Indicator: A small yarn or foam indicator is your tool on this water, especially in the meadow beats where you can’t rely on tight-line feel to register takes. Set it about 18 inches above the dropper. In water this shallow and clear, subtlety in indicator choice (small, neutral-colored) saves fish.
Where to Fish and How to Move
The meadow water above Spinney isn’t a place to camp on a single run. The trout are distributed, spooky, and quick to bolt if the light or presentation is wrong. Work the slower current seams where the main flow breaks around grass and small rises in the channel. These are the zones where trout can hold without burning energy, and they’re also where emergers collect naturally.
Approach from below and cast up and slightly across, letting the rig drift tight to any obstruction—a grass clump, a slight depression, the inside of a gentle bend. The best takes often come on the first or second drift through a likely spot; after that, the fish have either eaten or spooked. Move on. Cover water.
Avoid the very shallow flats that look barren in midday light. Fish them early in the morning or after 4 p.m. when the light angle changes and the fish are less visible. And keep a low profile; this is not a water where standing upright and false-casting wins converts. Kneel, move slowly, and let your drift do the talking.
Late-Day Caddis and the Temperature Window
By 5 or 6 p.m., the PMD emergence has faded and caddis begin to appear—nothing epic, but #14–16 tan or olive caddis in the evening air are real. At 28 CFS and with decent recent runoff, water temperature should still be in the upper 50s to low 60s (this is snowmelt-fed, not dam-controlled, so the thermals lag behind air temps but aren’t buffered either). That means the evening window—from 5 p.m. until dark—is genuinely productive. Caddis dry or caddis larva fished deeper will both work. Don’t discount the midge bite either; it runs all day and is underrated as an evening option when the obvious hatches fade.
Stewardship Note: Early Season and Access
If you’re not already holding a valid Colorado fishing license or SWA pass, you’ll need one to fish either the Tomahawk or Badger Basin. Check the current seasonal closures before heading out; early June can overlap with late spring spawning-protection windows on parts of this water. Nothing’s unconditionally open year-round, and the timing varies. Plan accordingly.