slug stringlengths 11 26 | name stringlengths 11 29 | country stringclasses 1
value | region stringclasses 8
values | species stringlengths 15 39 | lat float64 36.8 47.1 | lon float64 -121.25 -75.38 | usgs_gage_id int64 1.43M 14.1M | low_min_cfs int64 60 6k | ideal_low_cfs int64 100 8k | ideal_high_cfs int64 250 14k | blown_max_cfs int64 650 25k | season stringlengths 40 135 | best_months stringlengths 15 15 | flow_basis stringlengths 190 755 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
madison-river | Madison River | United States | Montana | Trout (brown & rainbow) | 44.86 | -111.34 | 6,038,500 | 600 | 800 | 1,500 | 2,500 | Year-round below Hebgen; prime July–October | Sep/Oct/Jul/Aug | Wade-fishing guide guidance for the upper Madison below Hebgen Lake (USGS 06038500): most fishable roughly 800–1,500 cfs, still fishable up to ~2,200, blown out above ~2,500, skinny below ~600. |
bighorn-river | Bighorn River | United States | Montana | Trout (brown & rainbow) | 45.32 | -107.94 | 6,287,000 | 1,500 | 2,500 | 4,500 | 9,000 | Year-round tailwater; prime October–April & summer | Oct/Nov/Mar/Apr | Guide-service flow guidance for the Bighorn tailwater below Yellowtail Afterbay Dam (USGS 06287000): prime drift/wade fishing roughly 2,500–4,500 cfs, fishable from ~1,500 and up to ~6,500, blown above ~9,000, low below ~1,500. |
missouri-river | Missouri River | United States | Montana | Trout (rainbow & brown) | 47.07 | -111.96 | 6,066,500 | 2,500 | 3,000 | 5,000 | 9,000 | Year-round tailwater; prime April–June & September–October | Sep/Oct/Apr/Jun | Craig-area guide guidance for the Missouri tailwater below Holter Dam (USGS 06066500): prime roughly 3,000–5,000 cfs, fishable from ~2,500 up to ~7,000, blown above ~9,000, low below ~2,500. |
gallatin-river | Gallatin River | United States | Montana | Trout (rainbow, brown & cutthroat) | 45.78 | -111.43 | 6,052,500 | 250 | 400 | 1,000 | 2,200 | Freestone — blown in spring runoff; prime July–October | Jul/Aug/Sep/Oct | Freestone flow guidance for the Gallatin (USGS 06052500): clear and wadeable roughly 400–1,000 cfs, fishable up to ~1,600, blown / off-color above ~2,200 (peak runoff late May–mid June), low below ~250. |
green-river | Green River | United States | Utah | Trout (brown, rainbow & cutthroat) | 40.91 | -109.42 | 9,234,500 | 700 | 800 | 2,600 | 4,600 | Year-round tailwater; prime September–October & spring | Sep/Oct/Apr/May | Flow guidance for the Green below Flaming Gorge Dam, "A" section (USGS 09234500 near Greendale): highly fishable across roughly 800–2,600 cfs, still fishable to ~3,500, blown above ~4,600, low below ~700. |
san-juan-river | San Juan River | United States | New Mexico | Trout (rainbow & brown) | 36.81 | -107.66 | 9,355,500 | 350 | 500 | 1,000 | 5,000 | Year-round tailwater; prime October–March | Oct/Nov/Jan/Feb | Quality-Waters flow guidance for the San Juan below Navajo Dam (USGS 09355500 near Archuleta): prime roughly 500–1,000 cfs, fishable from ~350 and up to ~2,500, blown above ~5,000, low below ~350. |
colorado-river-lees-ferry | Colorado River at Lees Ferry | United States | Arizona | Trout (rainbow) | 36.86 | -111.59 | 9,380,000 | 6,000 | 8,000 | 14,000 | 25,000 | Year-round tailwater; prime November–April | Nov/Dec/Mar/Apr | Flow guidance for the Colorado tailwater at Lees Ferry below Glen Canyon Dam (USGS 09380000): trout fished across roughly 8,000–14,000 cfs, fishable from ~6,000 up to ~18,000 with the daily dam fluctuation, blown above ~25,000, low below ~6,000. |
fryingpan-river | Fryingpan River | United States | Colorado | Trout (rainbow & brown) | 39.36 | -106.82 | 9,080,400 | 60 | 100 | 250 | 900 | Year-round tailwater; prime July–November | Sep/Oct/Nov/Jul | Flow guidance for the Fryingpan below Ruedi Reservoir (USGS 09080400 near Ruedi): prime roughly 100–250 cfs, fishable from ~70 and up to ~450, blown above ~900 (high summer releases), low below ~60. |
yellowstone-river | Yellowstone River | United States | Montana | Trout (brown, rainbow & cutthroat) | 45.5972 | -110.5665 | 6,192,500 | 1,300 | 2,000 | 7,000 | 14,000 | Freestone — blown in spring runoff; prime July–October | Sep/Oct/Aug/Jul | Guide guidance for the Yellowstone through Paradise Valley and Livingston (USGS 06192500 near Livingston): fishes well up to about 10,000 cfs, with the town stretch best below ~7,000 cfs. Spring runoff can push it past 20,000 cfs in late May–June (the gage's own June median is ~12,600 cfs), and late-summer base flows d... |
big-hole-river | Big Hole River | United States | Montana | Trout (brown, rainbow & grayling) | 45.5266 | -112.7017 | 6,025,500 | 250 | 500 | 1,800 | 5,000 | Freestone — high in spring runoff; prime June–September, low and warm in late summer | Jul/Sep/Jun/Aug | Flow guidance for the Big Hole near Melrose (USGS 06025500): the river averages around 1,000 cfs. Above ~3,000 cfs wading becomes very difficult and only experienced boaters should float; above ~5,000 cfs it should not be floated at all. The lower river closes if flow drops near 100 cfs, and late-summer low water with ... |
beaverhead-river | Beaverhead River | United States | Montana | Trout (brown & rainbow) | 45.1161 | -112.7505 | 6,016,000 | 200 | 500 | 1,000 | 1,800 | Year-round tailwater; prime July–October | Sep/Oct/Aug/Jul | Flow guidance for the Beaverhead tailwater below Clark Canyon Reservoir (USGS 06016000 at Barretts): prime float fishing between the reservoir and Barretts Diversion runs roughly 600–1,000 cfs, normal conditions fall between about 500 and 1,000 cfs, and wade anglers prefer the upper river nearer 300 cfs. Releases are s... |
blackfoot-river | Blackfoot River | United States | Montana | Trout (rainbow, brown & cutthroat) | 46.8994 | -113.7563 | 12,340,000 | 500 | 800 | 2,800 | 5,000 | Freestone — blown in spring runoff; prime July–September | Jul/Aug/Sep/Jun | Flow guidance for the Blackfoot near Bonner (USGS 12340000): around 2,500 cfs is prime for float fishing and bank wading. The river runs high and off-color through the May–June snowmelt — the gage's own May and June medians are above 4,000 cfs — and settles toward 600–800 cfs by late summer. It is wide, deep and swift,... |
henrys-fork | Henry's Fork | United States | Idaho | Trout (rainbow & brown) | 44.4167 | -111.3947 | 13,042,500 | 400 | 800 | 1,200 | 1,800 | Year-round tailwater below Island Park Dam; prime June–September | Jul/Jun/Sep/Aug | Flow guidance for the Box Canyon reach below Island Park Dam (USGS 13042500 near Island Park): the ideal window is roughly 800–1,200 cfs. Approaching and above ~1,200 cfs floating beats wading — fish spread into softer pockets and seams behind mid-channel boulders rather than holding typical lies — and winter drawdowns... |
south-fork-snake-river | South Fork of the Snake River | United States | Idaho | Trout (cutthroat, brown & rainbow) | 43.3508 | -111.2189 | 13,032,500 | 1,200 | 6,000 | 13,000 | 20,000 | Year-round tailwater on irrigation releases; prime July–October | Sep/Aug/Jul/Oct | Flow guidance for the South Fork below Palisades Dam (USGS 13032500 near Irwin): summer irrigation releases hold the river around 8,000–12,000 cfs and it fishes well across that band — guide reports call ~11,000 cfs stable and productive and ~14,000 cfs high. Flows fall to roughly 1,000–1,600 cfs once irrigation ends i... |
arkansas-river | Arkansas River | United States | Colorado | Trout (brown & rainbow) | 38.6522 | -106.0511 | 7,091,200 | 150 | 250 | 900 | 2,200 | Year-round; prime August–October once runoff and raft traffic drop | Sep/Oct/Aug/Apr | Flow guidance for the Browns Canyon / Buena Vista–Salida reach (USGS 07091200 near Nathrop): roughly 225–300 cfs is ideal for wading and for crossing to the far bank away from the highway, and the river wades well near 275 cfs with excellent clarity once rafting flows drop after mid-August. Float flows run higher throu... |
south-platte-river | South Platte River | United States | Colorado | Trout (rainbow & brown) | 39.26 | -105.2219 | 6,701,900 | 80 | 150 | 400 | 800 | Year-round tailwater; fishes all twelve months, peaks spring and fall | Sep/Oct/Apr/May | Flow guidance for the Deckers and Cheesman Canyon reach (USGS 06701900 below Brush Creek near Trumbull): the ideal range at Deckers is about 150–400 cfs, with roughly 200 cfs ideal for wading and sight-fishing and ~270 cfs reported as ideal flows. Releases from Cheesman Reservoir set the level, so the river holds shape... |
roaring-fork-river | Roaring Fork River | United States | Colorado | Trout (rainbow, brown & cutbow) | 39.5467 | -107.3308 | 9,085,000 | 400 | 700 | 2,500 | 5,000 | Freestone — high in spring runoff; prime July–October | Sep/Oct/Aug/Jul | Flow guidance for the lower Roaring Fork at Glenwood Springs (USGS 09085000): roughly 700–2,500 cfs is the ideal drift-boat range and 150–700 cfs fishes best on foot, with floating getting technical below ~700 cfs. The Gold Medal Basalt-to-Carbondale water wades well around 200–350 cfs on its own upstream gages. Snowme... |
deschutes-river | Deschutes River | United States | Oregon | Trout (redside rainbow) & steelhead | 44.726 | -121.247 | 14,092,500 | 3,000 | 3,800 | 5,500 | 8,000 | Year-round regulated tailwater; prime June salmonfly & September–October steelhead/redside | Sep/Oct/Jun/Aug | Flow guidance for the lower Deschutes below the Pelton–Round Butte complex (USGS 14092500 near Madras, which sits above the popular Maupin water with no major uncontrolled tributary between): the lower river is a stable, dam-regulated tailwater typically running 3,500–5,500 cfs year-round, and the gage's own daily perc... |
west-branch-delaware-river | West Branch Delaware River | United States | New York | Trout (wild & holdover brown & rainbow) | 42.003 | -75.3835 | 1,426,500 | 200 | 400 | 1,000 | 1,500 | Year-round Cannonsville Reservoir tailwater; prime June–September as a cold-water summer refuge | Jul/Aug/Jun/Sep | Flow guidance for the West Branch below Cannonsville Reservoir (USGS 01426500 at Hale Eddy): 200–400 cfs wades easily, 400–700 cfs is great wading and floating with the river staying cool, 700–1,000 cfs is the "best of both worlds" for floating and still-wadeable water, and 1,000–1,500 cfs needs a wading staff and care... |
provo-river | Provo River | United States | Utah | Trout (wild brown & rainbow) | 40.4841 | -111.4635 | 10,155,500 | 100 | 150 | 350 | 650 | Year-round Jordanelle Dam tailwater; prime fall (Sept–Oct) and winter midge fishing, June spring-runoff pass-through is the rough patch | Sep/Oct/Mar/Nov | Flow guidance for the Middle Provo below Jordanelle Dam (USGS 10155500 near Charleston): 150–300 cfs is the cited ideal wading band with ~200 cfs the sweet spot, flows fish well up to about 650 cfs, and below ~150 cfs fish get spooky in skinnier water. The gage's own daily percentile record shows this river holds close... |
River Fishable-Flow Bands — 20 Western Trout Rivers, USGS Gage IDs & Cited Thresholds (2026)
Fishable-flow-band data for 20 western North American trout rivers: the USGS real-time streamflow gage that measures each river, and the discharge thresholds (cfs) that separate low/skinny, fishable, prime, and blown-out/off-color conditions. Each threshold is cited to guide-service or outfitter flow guidance, cross-checked against the gage's own historical percentile record.
Why this exists
Live USGS discharge tells you the CURRENT number; it does not tell you whether that number is good
for fly fishing on that specific river. A "prime" flow on a small tailwater like the Fryingpan
(150 cfs) would be a trickle on the Colorado at Lees Ferry (10,000 cfs) — the band is per-river,
not a universal rule. This dataset is the lookup table that turns a live cfs reading into a verdict.
Columns
| column | meaning |
|---|---|
slug |
stable identifier used on besttimetofish.com. |
usgs_gage_id |
the USGS site number (waterdata.usgs.gov/nwis) whose live instantaneous discharge feeds the verdict — re-verified live at entry time, not just pulled from USGS's "active sites" list (that list includes gages that stopped reporting years ago). |
low_min_cfs |
below this discharge, the river is skinny/low — fish are spooky, wading is easy but fish are stressed. |
ideal_low_cfs / ideal_high_cfs |
the prime fishable window. |
blown_max_cfs |
above this, the river is blown out — high and typically off-color. |
season |
tailwater (dam-buffered, fishes closer to year-round) vs freestone (blows out in spring runoff) and the practical prime window. |
best_months |
the months this river fishes best, ranked. |
flow_basis |
the cited source for the thresholds — guide-service or outfitter flow guidance for that specific reach, cross-checked against the gage's own USGS daily percentile record. |
Sourcing caveat, stated plainly. Thresholds are guide/outfitter judgment calls tied to a specific reach of each river (not the whole watershed), cross-checked against USGS percentile data at entry time. Rivers change; verify current guidance before a trip.
Source and license
Compiled and maintained by Best Time to Fish (besttimetofish.com) — live USGS flow scored against these bands for a real-time fishability verdict per river. Licensed CC-BY-4.0.
- Downloads last month
- 24