South Platte — Above Spinney Hatch Report

2 CFS: A Genuine Low-Water Week in the Meadows

We’re running 2 CFS on the Middle Fork right now—genuinely thin for this water, even by the standards of a small headwater stream. To put that in perspective: normal low-water baseline here sits around 15 CFS, so we’re well below what you’d call “typical,” even for late summer. This isn’t a crisis, and it doesn’t mean the fishing is dead, but it does mean the fish are tighter, the water is warmer, and your approach needs to be precise rather than forgiving.

On a freestone meadow stream this size, 2 CFS concentrates trout into the few pockets that still hold decent depth—the inside bends where the channel hasn’t braided into shallow runs, the undercut banks where a little current still moves, the slot behind a boulder that’s now a relative island. The open meadow character of this water, which normally lets you cover ground and find scattered feeders, becomes a liability this week: every fish is in a known hiding spot, and they see you coming from a long way off across the flat.

Water temperature matters here too. With flow this low and mid-August heat bearing down, you’re looking at water that’s likely pushing into the low to mid-60s by afternoon, especially in the shallower meadow sections. That’s not a shutdown, but it is fish-stress territory. Fish will feed, but they’re less aggressive, and they’re less forgiving of a sloppy cast or a heavy tippet landing 18 inches away. Keep your sessions shorter and concentrate your time in the early morning and late evening windows—the water will be coolest, the fish least spooked, and your odds of a solid hookup highest.

What’s Hatching: Small Stuff, All Day

August on the Middle Fork above Spinney is dominated by small mayflies and the year-round midges that make this water fishable even when bigger hatches fade. Right now, expect:

PMDs (pale morning duns) in #16–18 are still on the water in the early part of the day, though the emergence windows are narrower and less dramatic than they were in July. When they do come off, it’s usually between 7 and 9 a.m., and the spinners return to lay eggs in the late afternoon—but with water this low, neither window is a grand slam. Fish will take the naturals if they’re in position, but you can’t rely on a hatch to make the bite.

Trico spinners (#20–24) are the reliable morning play. Tricos are small, they’re consistent, and they’re happening every morning right now—but again, with 2 CFS, they’re not triggering aggressive rises. You’ll see the occasional sip, usually from a fish already in a good lie, not a roaming feeder looking for the next meal.

Midges are the foundation. Black Beauty, Mercury Midge, Zebra Midge, and RS2 emergers in #20–24 fish all day on this water. They always do. The water clarity is good with this low flow, so size down to #22–24 and fish them small and realistic. Midges are your fallback when the mayfly spinners slow down, and they’re your confidence fly when you’re not certain what the fish are keyed on.

Terrestrials matter on warm afternoons—ants and beetles in #14–16, hoppers in #12–16 if the meadow grass is tall and windy. At 2 CFS, the fish are close to the banks, and a hopper or ant landed right at the edge of the grass can draw a response from a bank-holding trout that won’t look at a nymph.

Caddis will appear in the evenings, but it’s light activity at this flow. Have some small tan or olive caddis dries in #16–18 on hand, but don’t expect a blanket rise.

The Rig: Tight, Sparse, Deep

At 2 CFS, you’re not covering much water. You’re hunting. That means your approach is pick-and-place, not systematic dredging.

For nymphing (the high-percentage play): Rig a dropper setup with a heavier anchor fly and a lighter pattern above it. Use a #16 Barr’s Ugly Bug or small tungsten Pheasant Tail as your point fly—just enough weight to tick bottom without dragging through every run. Tie a #18–20 PMD emerger or RS2 18 inches up the leader as your dropper. Split shot is minimal—just enough to get the anchor fly to the bottom of the deeper slots; at this flow, you don’t need much. Use 4X or 5X tippet on the dropper; 5X if the light is clear and the fish are spooky (they will be). With 2 CFS and clear water, go smaller and thinner than you would at normal flows.

Use a small indicator if you want—a yarn or foam bit, not a bulky strike indicator—but serious low-water fishing on this meadow water often works tighter: dead-drift a bit of slack, feel the tick, set hard. The tight-line approach keeps you in better contact when the takes are soft and the fish are lethargic.

For dry-dropper (when spinners or PMD emergers are a real option): Fish a small adult PMD (#16–18) or Trico spinner imitation (#22–24) as your dry, with a midge emerger (#22) or small nymph dropper 12–18 inches below on 5X. This works best in the early morning (Trico window) and late afternoon (PMD spinner window). On a meadow stream this exposed at this low flow, your presentation needs to be delicate—false cast less, land softer, and expect refusals. The dry is your visual indicator; the dropper is your converter when the fish look but don’t eat the top.

For dry flies alone (late afternoon, terrestrials, and evening): Small ant or beetle patterns in #14–16, fished tight to the banks. Hoppers in #12–16 if the breeze is up and the grass is moving. Low-flow meadow fish are skittish, so a delicate presentation matters more than perfect drift. Land the fly 2–3 feet upstream of the bank and let it float. Be ready for a quick take, because a spooked fish won’t eat twice.

Where to Fish: The Deep Slots and Bank Cover

With 2 CFS, forget the flats. Forget trying to cover the open meadow systematically. The fish are in three places:

Inside bends where the channel deepens—even if it’s only 18 inches of water, that’s holding depth at this flow. The current still moves slightly through these bends, and they’re the most comfortable resting spots. Fish these with a dropper rig, slow, methodical, letting the nymph do the work. Expect takes to be soft.
Undercut banks and overhanging grass—especially where a meadow bank has eroded and created a little pocket. Fish at the very edge of the undercut, let a midge or small nymph work up into the shade, and be ready to set quickly. These fish are hiding, and they’ll eat with conviction if they commit.
Boulder and root-ball lies—anywhere there’s structure that breaks the current and provides cover. At 2 CFS, these are true fish magnets. A small dropper nymph fished right in the seam between the obstruction and the open water will connect. Cast upstream, mend once, and let gravity and current do the work.

Avoid the shallow meadow runs and wide, open flats. The fish aren’t there at this flow. Period.

One Tactical Note: Fish Early, Fish Cool

At 2 CFS in mid-August, your window is morning and evening. Water temperature peaks in the afternoon, stress goes up, and fish stop feeding aggressively. Arrive early—dawn or slightly before—and fish the Trico spinner window and the PMD emergence if there is one. Stop by midday, rest the water, and return in the last two hours before dark to fish terrestrials and small dries. It’s not glamorous, but it’s how you actually catch fish on this water right now.

And respect the SWA boundaries. Badger Basin and Tomahawk are public, but they’re fragile meadow water—artificial lures only in Tomahawk, and seasonal spawning closures apply. Check your regs before you head up.