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Wyoming

North Platte River

Wyoming·North Platte Basin·42.55° N, 106.75° W
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Solunar · next 7 days

About North Platte River

Central Wyoming's North Platte is a string of dam-controlled tailwaters that produces some of the highest trout densities in the West. The named fly fishing water is concentrated in three sections — Miracle Mile, Fremont Canyon, and Grey Reef — together totaling about 100 miles of cold, fertile, year-round river. Grey Reef in particular is rated Blue Ribbon by Wyoming Game & Fish and supports more than 8,000 trout per mile in its upper twelve miles, averaging 16-19 inches.

It fishes as a tailwater first. Flow is regulated by Kortes, Pathfinder, and Alcova / Gray Reef dams; releases are tuned by the Bureau of Reclamation for irrigation rather than fishing, so seasonal flow patterns matter a lot. Sow bugs, scuds, and small midges drive the bug calendar — these aren't classic salmonfly-and-PMD freestoners. Mid-summer Trico spinner falls and fall BWO hatches open dry-fly windows, but the daily bread-and-butter is deep nymphing heavy attractor rigs through long runs. Streamer fishing is excellent fall through spring, especially for the resident brown trout in the deeper holding water below Grey Reef and through Miracle Mile.

The corridor town is Casper, an hour east of Grey Reef and 90 minutes from Miracle Mile and Fremont Canyon. Driving distances put the river outside most weekend trip ranges, which keeps pressure manageable even on the famous water — locals and destination anglers split the traffic. The 2026 regulation refresh tightened gear restrictions: single-point barbless hooks are now required on Miracle Mile, Alcova Afterbay, Fremont Canyon, and Grey Reef; pegged attractors are banned at Fremont Canyon and Grey Reef; the artificial-flies-and-lures section at Grey Reef extends downstream to Government Bridge; and a new spawning closure from Ledge Creek downstream is in effect April 1 – May 15 each year. Note that current Grey Reef flow data comes from NWPS observation only — the USGS Alcova gauge no longer reports live data.

Species

  • Rainbow Trout
    Abundant · Year-round · 14-22"

    Wild-reproducing in Grey Reef (the upper 12 miles holds 8,000+ fish per mile), supplemented by stocking elsewhere. Average Grey Reef rainbow runs 16-19 inches; trophy fish over 24 inches show every season.

  • Brown Trout
    Common · Sep-Nov · 14-26"

    Concentrated in Miracle Mile and the deeper holding water below Grey Reef. Best targeted on streamers in fall pre-spawn aggression.

  • Cutthroat Trout
    Rare · Year-round · 12-16"

    Scattered presence; not a primary target.

  • Mountain Whitefish
    Common · Year-round · 10-16"

    Native and present throughout the system. Take small nymphs aggressively and often save slow days.

SpeciesAbundanceBest SeasonSize
Rainbow TroutAbundantYear-round14-22"
Brown TroutCommonSep-Nov14-26"
Cutthroat TroutRareYear-round12-16"
Mountain WhitefishCommonYear-round10-16"

Sections

5 reaches

Grey Reef to Casper

FloatBrown Trout · Rainbow Trout

Roughly 55 miles of float water from below Government Bridge through Bessemer Bend and into Casper. Bigger water than the upper tailwater, productive for brown trout in the deep holding runs and rainbow trout through the riffles. Less crowded than the Reef itself.

Best for: Brown trout and rainbow trout on streamers, attractor nymphs, and hopper-droppers in summer. Multi-day float water for experienced rowers.

Grey Reef Tailwater (Gray Reef Dam to Government Bridge)

Wade & FloatBrown Trout · Rainbow Trout

The signature WY North Platte fly fishing section. Twelve miles below the Gray Reef Dam holds 8,000+ wild rainbow trout per mile, averaging 16-19 inches. Float fishing from the Lusby Public Access put-in is the standard guide trip. Artificial flies and lures only, single-point barbless, no pegged attractors as of 2026. Spawning closure below Ledge Creek April 1 – May 15.

Best for: Trophy wild rainbow trout on sow bugs, scuds, eggs, midges, and BWOs. Brown trout on streamers in fall and spring. The Blue Ribbon guide-float section.

Fremont Canyon (Pathfinder Dam to Alcova Reservoir)

WadeBrown Trout · Rainbow Trout

Three miles of meadow water below Pathfinder Dam followed by a rugged canyon of vertical walls and pocket water. Typical flows are very low — under 100 CFS — making this a wade fishery only. Pegged attractors banned as of 2026.

Best for: Rainbow trout and brown trout on small nymphs, midges, and tight technical dry-fly. Drive-in access at the Pathfinder Dam parking area or the bottom of the canyon. Walk-and-wade only.

Miracle Mile (Kortes Dam to Pathfinder Reservoir)

Wade & FloatBrown Trout · Rainbow Trout

Five to eight miles of tailwater (length fluctuates with Pathfinder reservoir level) below Kortes Powerplant. Steep canyon walls, large boulders, pocket water, classic riffle-and-run scenarios. WY G&F electrofishing shows ~3,200 trout per mile. Single-point barbless hooks required as of 2026.

Best for: Rainbow trout and brown trout on stonefly nymphs, sow bugs, scuds, and streamers in fall. Wade or row a small raft.

Saratoga / Pick Bridge (Upper River)

Wade & FloatBrown Trout · Rainbow Trout

The upper free-flowing North Platte between Saratoga and Sinclair (above Seminoe Reservoir). Freestone-style water with stonefly hatches, less famous than the tailwaters downstream. Some private access; public reach near Saratoga and around Pick Bridge.

Best for: Wild brown trout and rainbow trout on stonefly nymphs, streamers, and attractor dries. Best Jul-Oct.

At a glance

Ideal wading flow
400–1,500 cfs
Blow-out
>4,000 cfs
Ideal water temp
40–58°F
Best seasons

October-November (brown pre-spawn, BWO, streamers), March-April (rainbow spawn, midges, BWO), July-August (Trico spinner falls, dry-fly windows). The tailwaters fish 12 months — water temperature is stable year-round.

Regulations

2026 regulations tightened gear restrictions in the Miracle Mile, Fremont Canyon, and Grey Reef tailwaters. Single-point barbless hooks required throughout these sections; pegged attractors banned at Fremont Canyon and Grey Reef; artificial flies and lures only at Grey Reef from the dam downstream to Government Bridge; spawning closure below Ledge Creek April 1 – May 15.

  • Miracle Mile (Kortes Dam to Pathfinder Reservoir): single-point barbless hooks required; year-round
  • Fremont Canyon (Pathfinder Dam to Alcova Reservoir): single-point barbless required; pegged attractors prohibited
  • Grey Reef (Gray Reef Dam to Government Bridge): artificial flies and lures only; single-point barbless; pegged attractors prohibited; spawning closure below Ledge Creek April 1 – May 15
  • Standard WY trout limits apply elsewhere on the river (6 trout daily)
  • WY resident or non-resident fishing license required throughout
  • Commercial guides must register their boats annually with WY G&F (mandatory as of 2026)

The Bureau of Reclamation manages flow releases on this system for irrigation. Spring 'flush' flows above 4,000 CFS can briefly make Grey Reef unfishable. Check the NWPS Gray Reef gauge before driving in.

Source: Wyoming Game and Fish Department — Fishing Regulations. Regulations change annually. Verify before fishing.

Getting there

Casper, WY

30 min from Casper to Grey Reef, 90 min from Casper to Miracle Mile; 3 hrs from Cheyenne; 4 hrs from Denver; 8 hrs from Salt Lake City

Fly shops

  • Ugly Bug Fly ShopCasper
  • Wyoming AnglersCasper
  • Crazy Rainbow Fly FishingCasper
  • Platte River Fly ShopCasper

Camping: Public camping at Pathfinder Reservoir (Pathfinder NWR), Alcova Reservoir, and the Miracle Mile (BLM dispersed camping). Streamside lodges at North Platte Lodge (Alcova) and Grey Reef Wingshooting & Fly Fishing Lodge. Hotels and short-term rentals in Casper.

Grey Reef public access starts at the Lusby Public Access put-in below the dam. Miracle Mile has dirt-road BLM access from Kortes Powerplant downstream. Fremont Canyon access is foot-only from the Pathfinder Dam parking area or the bottom of the canyon. Float trips are the standard Grey Reef guide trip; Miracle Mile and Fremont Canyon are wade-only.

Fishing reports

Recent reports from local fly shops, guides & lodges on North Platte River. Each links out to the source. We show a short attributed excerpt and never republish the full report.

Ugly Bug Fly Shop · Casper3 weeks ago
New Comment Period Opens for Seminoe Pumped Storage Project

“The fight to protect the North Platte River system is far from over. Recently, the Bureau of Land Management (BLM) announced that additional environmental review will be required before amendments to the Rawlins Resource Management Plan can move forward. This is an important…”

Ugly Bug Fly Shop · Casper3 weeks ago
Fishing Report 09/21/2026

“Fall is starting to show up on the North Platte, and fishing is trending the right direction. Cool nights have helped water temperatures across the system. Hoot Owl restrictions have also been lifted. For a hot, dry year across much of the West, the North Platte came through in…”

Ugly Bug Fly Shop · Casper4 weeks ago
WFG Lifts Voluntary Closure (Casper Region)

“Good news, anglers! Wyoming Game and Fish has lifted the voluntary fishing closure below Lusby, marking a welcome change. Hot temperatures and low water conditions kept anglers on their toes for much of the season. Many fishermen adjusted their schedules, quit early, or stayed…”

Ugly Bug Fly Shop · Casper5 weeks ago
Quick Report 09/09/2026

“Not much has changed on the ol fishing report front. The good news is that water temperatures continue to improve throughout the North Platte system. We aren’t getting too comfortable just yet, though. We still keep temperatures top of mind, and the voluntary closure below Lusby…”

Ugly Bug Fly Shop · Casper5 weeks ago
Wyoming Hunting Season Is Here – Turn Your Hunt Into a Day on the Water

“Ahhhh. The sweet smell of hunting season. We wait all year for this, and it has finally arrived. First off, congratulations to everyone who drew a tag this season. For those who came up empty, we feel your pain. We are happy to lament with you. We also want to welcome hunters…”

Ugly Bug Fly Shop · Casper6 weeks ago
Ugly Bug Fly Shop Hours and Labor Day Weekend

“While fishing season still has plenty of gas left in the tank, we’ve reached that time of year again. As of September 1, Ugly Bug Fly Shop has returned to our fall business hours. You can find us in the shop Monday through Friday from 9:00 AM to 5:30 PM. We are open Saturdays…”

Ugly Bug Fly Shop · Casper6 weeks ago
Quick Report 09/03/2026

“Not gonna lie, we’re pretty stoked to flip the calendar to September. Cooler nights are rolling in. Those cooler nights matter. With both Grey Reef and the Miracle Mile holding at 500 CFS, every degree helps. The cooler weather should keep conditions moving in the right…”

Ugly Bug Fly Shop · Casper7 weeks ago
Seminoe Pumped Storage Project Community Meeting Set for September 1

“The fight for Wyoming’s waters, wildlife, and public lands continues. Join us on Tuesday, September 1 at 6PM, for another Seminoe Pumped Storage Project community meeting at Ugly Bug Fly Shop. We will host the meeting in person at the shop and offer a Zoom option for those who…”

Ugly Bug Fly Shop · Casper7 weeks ago
Quick Report 08/25/2026

“Here’s a quick North Platte fishing report and conditions update. Grey Reef has dropped to 500 CFS. Recent rain events have pushed color throughout the entire system, and conditions get progressively dirtier the farther downstream you travel. The stretch closest to the dam…”

Ugly Bug Fly Shop · CasperAug 19, 2026
Upcoming Event: Simms Working Wader Tour!

“For more than 40 years, Simms has stood alongside guides, fly shops, and anglers on rivers across the world. This summer, they are bringing that commitment directly to fishing communities throughout the Rocky Mountain West with the Simms Working Wader Tour. On Thursday, August…”

Ugly Bug Fly Shop · CasperAug 19, 2026
Quick Report 08/19/2026

“Just popping in with a quick North Platte fishing report. The Casper area took a hit from a heavy rainstorm last week. The runoff pushed a lot of color into the river and muddied things up below Lusby. While the fishing suffered for a bit, we welcomed the moisture with open…”

Ugly Bug Fly Shop · CasperAug 12, 2026
Fishing Report 08/12/2026

“August is flying by, and while summer isn’t quite done with us yet. Rest assured there will be a light at the end of the tunnel. The Reef is holding steady at 800 CFS, and fishing continues to be productive. The voluntary closure below Lusby remains in effect. We’ve been…”

Ugly Bug Fly Shop · CasperAug 10, 2026
The Fight for Seminoe Isn’t Over

“The Seminoe Pumped Storage Project has continued to move through the federal regulatory process, but that doesn’t mean we’re throwing in the towel. If anything, the fight is getting louder. Recent conditions at Seminoe Reservoir are putting the concerns we’ve been raising into…”

Ugly Bug Fly Shop · CasperAug 7, 2026
WGF: New Voluntary Closures (Cody Region)

“Due to unseasonably warm conditions, water temperatures are regularly climbing above 70°F and, in some areas, not dropping enough overnight to give trout a chance to recover. The Wyoming Game and Fish Department is asking anglers to adjust accordingly on portions of the Bighorn…”

Ugly Bug Fly Shop · CasperAug 5, 2026
Fishing Report 08/05/2026

“Happy dog days of summer! Honestly, not much has changed from the bug side of things. The Reef sits at 800 CFS, and the hatches have stayed consistent all summer. Expect tricos first thing in the morning, followed by caddis and yellow sallies. If you find fish keyed in on one of…”

Ugly Bug Fly Shop · CasperAug 4, 2026
NEW PRODUCT: Olivia Mae Designs

“Every once in a while, something new comes through the door that gets us excited, and that’s exactly what happened when Olivia stopped by the shop with her artwork. She showed us a few of her stickers, and we were hooked right away (pun intended). Olivia is a 15 year old angler…”

Ugly Bug Fly Shop · CasperJul 30, 2026
WGF: Voluntary Warm-Water Closure

“It is no secret that this has been a strange water year across the West. Between lingering drought conditions, below-average runoff in many areas, and a stretch of hot summer temperatures, anglers are seeing the effects firsthand. As of yesterday, the Wyoming Game and Fish…”

Ugly Bug Fly Shop · CasperJul 30, 2026
WGF: Voluntary Closure (Casper Region)

“It is no secret that this has been a strange water year across the West. Between lingering drought conditions, below-average runoff in many areas, and a stretch of hot summer temperatures, anglers are seeing the effects firsthand. As of yesterday, the Wyoming Game and Fish…”

Ugly Bug Fly Shop · CasperJul 29, 2026
Quick Report 07/29/2026

“Just popping in with a quick update on the Grey Reef. Flows have been dropped to 800 CFS. While the river is still fishing well, the lower flows combined with warm temperatures in the forecast mean it’s time to be a little more mindful of conditions on the water. The good news…”

Ugly Bug Fly Shop · CasperJul 23, 2026
Fishing Report 07/23/2026

“July is flying by, and fishing has continued to hold up. On the Grey Reef, flows are currently running at 2,200 CFS, and the morning Trico hatch has been nothing short of prolific.As the morning progresses, Pale Morning Duns take over before giving way to caddis and Yellow…”

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Hoback River

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Fishing
Good
Flow
318cfs
steady · N Platte R above Seminoe Reservoir near Sinclair
Water temp
—
Flow vs normal
Below Normal
35th percentile for mid-October

Sub-freezing temperatures 22 to 26 degrees expected.

Freeze Warning · 12 areas · through Fri 9:00 AM · NWS Riverton WY
What this means

A warning is the National Weather Service's most urgent level. The event is happening or about to happen in this area.

WHERE...Portions of central, north central, and south central Wyoming.

WHEN...From 11 PM this evening to 9 AM MDT Friday.

IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation, and possibly damage unprotected outdoor plumbing.

Take steps now to protect tender plants from the cold.

To prevent water pipes from freezing; wrap or drain or allow them to drip slowly.

Read the full product from NWS Riverton WY

Flow
318cfs
N Platte R above Seminoe Reservoir near Sinclair · stable
Water temp
—
Flow vs normal
Below Normal
35th percentile for mid-October
Median 395 cfs
Weather
33°F
Widespread Frost · near Alcova

Fishing conditions

Good
PoorSlowFairGoodPrime
How we rate this
Sat
10/17
—
MDE
Sun
10/18
—
MDE
Mon
10/19
—
MDE
Tue
10/20
—
MDE
Wed
10/21
—
MDE

MmorningDmiddayEevening

poorprime

Today
morning6:22a – 11:22aGood
midday11:22a – 2:25pGoodRising pressure
evening2:25p – 7:25pGoodFalling pressure
All day
Bright sun
Measured
318 cfs, a little low

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