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River canyon in the American Southwest

San Juan River Fishing Report: Flows, Hatches & Conditions

NM
intermediate-advanced

Quick Reference

WhatWhenKey Numbers
Quality WatersYear-round (fall best for crowds)15,000 trout/mile; 17" avg; 3.75 mi C&R section
Ideal flows300-500 CFS typical42-46°F water year-round; fishable all seasons
Fly sizesMidges #20-28; BWOs #20-246X-7X tippet essential; single barbless hooks
Texas HoleArrive before sunrise weekendsMost fish; most crowded; best hatch activity
Guided tripsWorth it for first-timers$400-500/day; Abe's; Fisheads
LicenseNM fishing license requiredCheck current regulations at wildlife.state.nm.us
FISHABLE
Updated yesterday
San Juan River
Fishable
Flow~491 CFS (stabilizing)
Trendstabilizing
Clarityclearing nicely (~4+ ft visibility)
Temp42°F at dam, ~48°F downstream
Vernille SJ Worm #8-14 (brown/black/natural)Lynch's Double Dot Egg #18 (orange blood dot)Rojo Midge #20-22 (gray/olive/brown)Midge Larvae #18-24 (black/cream/olive)
The 800 CFS elevated release from Navajo Dam ended June 10—the 20,000 acre-feet release of Jicarilla Apache Nation subcontracted water is complete (BOR Notice, May 19). Flows have dropped to ~491 CFS as of June 11 and are expected to hold in this range for a couple weeks (Orvis, June 11). Water clarity continues improving—visibility now 4+ feet following the dam gate change, up from 1 foot two weeks ago (Fisheads, June 8). Water temp holding steady at 42°F at the dam release (Orvis, June 11). With flows now in the ideal 300-500 CFS window, fish are concentrating back into classic holding lies—easier wading and more technical presentations required. Dry-fly season is fully underway: rising fish visible throughout the river eating midges and Baetis (About Trout, June 5). Downsize your patterns—the era of 'bigger and brighter' from the turbid weeks is over. Worm and egg patterns still productive as lead attractors—Vernille SJ Worm #8-14 and Lynch's Double Dot Egg #18. Foam Wing RS2 #18-24 and Rojo Midge #20-22 very consistent. Black latex/mono midges #22-24 productive subsurface. Midge hatches active from 11 AM; BWO hatches noon to 5 PM on overcast afternoons; caddis activity evenings on the lower river (Orvis, June 11). PMD hatches firing on the lower river near Simon Canyon (Orvis, June 11). Ant falls now active—mid-June through July—carry ant patterns #12-20 for the lower river. Afternoon air temps in the high 80s to low 90s. Mostly sunny forecast. NMDGF officers actively checking Quality Waters for licenses, barbless hooks, and two-fly limit—fines are steep. Highway 511 over Navajo Dam construction complete—no more traffic delays.
🎣 TACTICS RIGHT NOW
Dry Fly
Dry-fly season is in full swing—the gate change at Navajo Dam has cleared the river dramaticallywith visibility now 4+ feet and rising fish visible throughout the river (About TroutJune 5; FisheadsJune 8). With flows stabilized at ~491 CFSsurface fishing is the best it's been in weeks. Griffith's Gnat #18 (black/olive) for midge clusters in flat tailouts—midges hatching strongly from 11 AM producing consistent risers (OrvisJune 11). Parachute Adams #22 (dark wing) and Comparaduns #22 for Baetis risers on overcast afternoons—BWOs noon to 5 PM. PMD hatches established on the lower river near Simon Canyon alongside steady evening caddis activity—carry Elk Hair Caddis #16-18 (OrvisJune 11). Ant falls now active through July—carry ant patterns #12-20 for explosive dry-fly opportunities on the lower river when afternoon thunderstorms wash ants into the current. Best dry-fly water at Texas Hole bottom and Lower Flats where slower currents concentrate rising fish. Cloudier days producing bigger hatches—watch the forecast. Summer terrestrial opportunities growing: Chubby Chernobyls and Fat Alberts later in the day on the lower river. Use 6X-7X mono tippet for dries.
Nymph
Flows have settled to ~491 CFS—now in the ideal fishing range. Worm and egg patterns remain top producers: Vernille SJ Worm #8-14 (brown/black/natural) or Lynch's Double Dot Egg #18 as lead attractordrop to Rojo Midge #20-22 (gray/olive/brown)midge larvae #18-24Red Larva #16-22Foam Wing RS2 #18-24or Foam Wing #24 (OrvisJune 11). With clarity now 4+ feetdownsize and refine—smaller patternsfiner tippetsmore natural presentations. Black latex/mono midge #22-24 very productive subsurface. Fish concentrating in classic holding lies at current flows—seamsedgestraditional runssofter pockets. Wading comfortable at ~491 CFS. Use 4X fluorocarbon to lead fly5X-6X to dropper. Tungsten Rainbow Warrior #14 effective as a lead attractor (OrvisJune 11). Bunny leeches #6-8 and marabou jigs (black/chartreuse) #8-12 on the bottom with slow strips still drawing strikes but becoming less effective as clarity improves—fish them early morning or on overcast days. PMD nymphs worth adding on the lower river near Simon Canyon. Early mornings (7-10 AM) before wind builds are your best window for quality drifts.
Fishing excellent with flows stabilized at ~491 CFS in the ideal range—classic San Juan conditions. Morning (7-10 AM): best window for quality nymphing drifts before the wind builds. Worm/egg rigs tipped with midge droppers remain the bread-and-butter technique. Streamer fishing worth throwing early on overcast mornings. Mid-morning to midday (10 AM-2 PM): peak midge hatch activity from 11 AM—fish rising to midge clusters in flat tailouts (Orvis, June 11). Transition from nymphing to dries as the hatch builds. Early to late afternoon (noon-5 PM): BWO hatches firing on overcast days, with PMD and caddis activity on the lower river near Simon Canyon. Ant falls now active—watch for explosive surface feeding after afternoon thunderstorms wash ants into the river. Dry-fly fishing the best it's been in weeks with 4+ feet of clarity. Texas Hole mornings still require early arrival on weekends—peak summer tourist season. Afternoon air temps in the high 80s to low 90s—stay hydrated, bring sun protection. NMDGF officers actively patrolling—licenses, barbless hooks, two-fly limit enforced.
FORECASTThe 800 CFS elevated release ended June 10 per BOR schedule—flows have dropped to ~491 CFS and are expected to hold in this range for a couple weeks (Orvis, June 11). The 20,000 acre-feet release of Jicarilla Apache Nation subcontracted water is complete (BOR Notice, May 19). Water clarity continuing to improve—now 4+ feet and getting better daily as flows stabilize at lower levels. Classic San Juan technical fishing has returned: concentrated fish in traditional lies, smaller flies, finer tippets. No major environmental release spikes (5,000+ CFS) expected this year. Summer hatch diversity peaking: midges all day, BWOs on overcast afternoons, PMDs and caddis established on lower river, ant falls active through July. Dry-fly fishing expanding significantly—the best surface fishing window of the year is now through mid-summer. Terrestrial opportunities (ants, beetles, larger foam dries) will grow through July on the lower river. Mostly sunny forecast with afternoon air temps in the high 80s to low 90s. Summer thunderstorms possible—bring rain gear and watch for lightning. Cloudier days produce larger hatches. Highway 511 over Navajo Dam construction complete—no more traffic delays.

Before You Go

You've heard the stats: 15,000 trout per mile. Fish averaging 17 inches. The San Juan River below Navajo Dam is, by the numbers, one of the most productive trout fisheries in North America.

But those numbers hide something important: these fish have PhD's in fly refusal. They've seen every pattern in your box, presented by thousands of anglers before you. The San Juan will humble you - and that's precisely why serious fly fishers keep coming back.

This isn't a place where you tie on an elk hair caddis and start catching fish. It's a place where you learn to fish size 24 midges on 7X tippet and celebrate when you finally crack the code.

Fly fishing in a mountain stream The San Juan's crystal-clear tailwater demands precise presentations and small flies.

Why the San Juan is Different

The Navajo Dam, completed in 1963, transformed the San Juan from a warm, muddy desert river into a cold-water trout factory. Water released from the bottom of the 402-foot dam stays a constant 42-46°F year-round, creating ideal conditions for rainbow and brown trout.

The result is a tailwater with staggering biomass. The 3.75 miles of Quality Waters below the dam hold an estimated 15,000+ trout per mile - mostly rainbows, with a healthy population of browns. These fish grow fat on a diet dominated by one thing: midges.

What makes the San Juan special:

  • Consistent flows (typically 300-500 CFS) year-round
  • Water clarity measured in feet, not inches
  • Year-round midge hatches - sometimes multiple per day
  • Blue-winged olive hatches in spring and fall
  • Fish that have seen it all and require technical presentations

The Quality Waters: Where to Fish

The first 3.75 miles below Navajo Dam are designated "Quality Waters" by New Mexico Game and Fish. This is catch-and-release only, artificial flies with single barbless hooks. Two flies maximum.

Texas Hole

The most famous (and crowded) spot on the river. A narrow gap funnels swift current into an 8-foot-deep pool where trout stack up in impressive numbers. The warmer water here supports more diverse insect life than the upper reaches.

  • Parking: 3.8 miles upstream from the Hwy 173/511 intersection
  • Why fish here: Highest fish concentration, best mayfly activity
  • The catch: Gets crowded, especially weekends. Arrive before sunrise for the best spots.

Upper Flats

Upstream from Texas Hole, the river spreads out and slows down. This is where you'll find some of the biggest fish - and the most technical fishing. Shallow, clear water means spooky fish that demand long, fine leaders and perfect drifts.

  • Parking: 4.4 miles upstream from the intersection
  • Why fish here: Trophy potential, less crowded
  • The catch: Harder wading, more technical presentations required

Lower Flats & Simon Canyon

Below Texas Hole, the river widens and meanders. More caddis activity here than upstream, along with scuds and aquatic worms. The Simon Canyon section is the warmest water in Quality Waters, supporting the most diverse bug life.

  • Parking: 2.7 miles upstream from the intersection
  • Why fish here: More insect variety, solitude
  • The catch: Longer walk from parking, fewer fish per mile than Texas Hole

Rainbow trout being held in a net San Juan rainbows average 17 inches, with plenty of fish pushing 20+.

Understanding San Juan Flows

Unlike freestone rivers, the San Juan's flow is controlled by Navajo Dam releases. This means consistent, predictable conditions - but you still need to know what the numbers mean.

Flow (CFS)Conditions
Under 250Low water - fish concentrated, easier wading, more pressure on fish
300-500Ideal range - normal operations, fish spread out, good wading
500-800Higher water - deeper wading, fish pushed to banks
Over 1,000Spring peak releases - difficult fishing, limited access

Current flows run around 300-350 CFS most of the year. Spring environmental releases can spike to 5,000 CFS for up to 60 days, mimicking natural conditions for native fish recovery downstream.

Check real-time San Juan River flows near Archuleta before you go.

The Flies That Actually Work

Forget your standard trout box. The San Juan is midge water, and you'll fish smaller flies here than anywhere else.

Midges (Year-Round, All Day)

The San Juan has reliable midge hatches every day - typically one mid-morning and another in the afternoon. These are your bread-and-butter flies:

  • Midge Larva (#22-28, black, cream, olive) - dead drifted deep
  • Zebra Midge (#20-24) - the universal San Juan pattern
  • RS2 (#22-24, gray) - poly wing emerger that works as both nymph and dry
  • Black Midge Cluster (#18-24) - for fish eating adults on the surface
  • Griffith's Gnat (#18-22) - when fish are on mating clusters

Blue-Winged Olives (Spring & Fall)

When baetis hatch on overcast days, the fishing can be exceptional:

  • Parachute Adams (#20-24, gray) - simple and effective
  • Sparkle Dun (#22-24) - emerger pattern
  • Pheasant Tail (#18-22) - standard nymph for baetis

Attractor Patterns

Not as critical here as other rivers, but worth having:

  • San Juan Worm (#14-18, red, orange, tan, brown) - the river's namesake pattern
  • Scuds (#16-18, olive, tan) - especially in Simon Canyon
  • Egg patterns (#16-18, peach, pink) - work year-round

The Tiny Fly Problem

If you've never fished #24-28 flies, prepare for frustration. A few tips:

  1. Use fluorocarbon tippet (6X-7X) - it sinks and is less visible
  2. Keep your flies clean - algae buildup kills the drift
  3. Carry a magnifier - you'll need it to thread these hooks
  4. Use a small strike indicator - standard bobbers spook fish in this clear water

Seasonal Patterns

Spring (March - May)

Baetis hatches kick into gear on cloudy afternoons. Look for rising fish in slower water, especially on overcast days. As water temps climb, fish become more active and willing to chase streamers.

Best approach: Morning nymphing with midge larvae, afternoon dry-fly fishing during BWO hatches.

Summer (June - August)

Peak tourist season brings crowds, but also the best dry fly action. Terrestrials (ants, beetles, hoppers) work in Simon Canyon. Midge hatches continue reliably. Water temps stay cold, so fish remain active all day.

Best approach: Early mornings for solitude, late afternoons for midge hatches. Fish early or miss the crowds.

Fall (September - November)

Many consider this the best time to fish the San Juan. Crowds thin, cottonwoods turn gold, and fish feed aggressively before winter. Baetis hatches return with intensity.

Best approach: All-day fishing is productive. September is prime time for dry flies.

Winter (December - February)

This is when you'll have the river to yourself. Water temperature stays constant, fish still eat, and the crowds disappear. The cold air doesn't mean cold water - the tailwater stays in the mid-40s year-round.

Best approach: Nymph deep with midge patterns. Fish are slower but definitely feeding. Heavy tippets, big flies, patient presentations.

Techniques That Work

Nymphing (The Primary Game)

Most of your fish will come subsurface. The standard San Juan rig:

  1. Lead fly: San Juan Worm or larger midge (#18-20)
  2. Dropper: Small midge pupa or RS2 (#22-26), 12-18" behind the lead
  3. Tippet: 4X to the lead fly, 5X-6X to the dropper
  4. Indicator: Small, visible, easy to move for depth adjustments

Key technique: Get your depth right and let the fly drift naturally without drag. Mend constantly. These fish have seen a million bad drifts.

Euro Nymphing

The San Juan is excellent euro nymphing water. The clear, consistent flows let you read fish reactions. Use 10.5-11' 2-4 weight rods to reach across currents without putting line on the water.

Dry Fly Fishing

When fish are rising - and they do rise - the dry fly fishing can be outstanding. Keys to success:

  • Long, fine leaders: 12' or longer, ending in 6X-7X
  • Mono tippet (not fluoro) - floats better
  • Precise casting: Put the fly in the fish's feeding lane, not 3 feet away
  • Watch your shadow: These fish spook at everything

Gear Recommendations

Rod: 9' 4-weight or 5-weight, fast action for mending and distance Alternative: 10-11' euro nymphing rod (2-4 weight) for tight-line techniques

Reel: Simple click-and-pawl or disc drag - you're not running fish into the backing here

Line: Weight-forward floating line. Consider a long-leader-specific taper for delicate presentations.

Leaders:

  • Nymphing: 9' 4X tapered, add tippet sections as needed
  • Dry fly: 12-15' 5X or 6X tapered, with fluorocarbon tippet for nymphs, mono for dries

Essential Accessories:

  • Magnifying threader (you'll need it for size 24+ flies)
  • Small strike indicators (yarn, small bobbers)
  • Hemostats for barbless hook removal
  • Rubber mesh net
  • Polarized sunglasses - essential for sight fishing in clear water

Regulations

The Quality Waters (first 3.75 miles below the dam) have specific rules:

  • Catch and release only - all trout must be returned immediately
  • Artificial flies only - single, barbless hook
  • Maximum 2 flies per line
  • Valid New Mexico fishing license required

Below the Special Trout Waters, regulations shift to statewide rules with bag limits. Check New Mexico Game and Fish for current regulations.

Access & Logistics

Getting There

The San Juan is in the northwest corner of New Mexico, about 26 miles east of Farmington. From Albuquerque, it's roughly 3 hours. From Denver, about 6-7 hours via Durango.

Nearest towns:

  • Navajo Dam (closest, limited services)
  • Aztec (15 miles, more amenities)
  • Farmington (30 miles, full services)

Parking Areas

Three main access points within Quality Waters:

  • Upper River: 4.4 miles from Hwy 173/511 intersection
  • Texas Hole: 3.8 miles from intersection
  • Lower Flats: 2.7 miles from intersection

Parking can fill early on weekends. Arrive before sunrise for Texas Hole access.

Lodging & Fly Shops

On the Water:

Guides:

A guided day runs $400-500 and is worth it for first-timers. The guides know exactly what's working and can cut your learning curve dramatically.

Common Mistakes

  1. Fishing too heavy: Light tippet (6X-7X) and small indicators are essential
  2. Ignoring fly cleanliness: Algae on your fly kills the drift - check constantly
  3. Casting too far: Most fish are closer than you think
  4. Wrong depth: If you're not occasionally ticking bottom, you're too high
  5. Arriving late: Texas Hole fills up by 8am on weekends
  6. Underestimating the cold: Even in summer, that 42°F water chills you fast

Using RiverReports

Before your trip, check:

  • San Juan River flows near Archuleta for real-time CFS
  • Historical flow comparisons to understand current conditions
  • Weather forecasts - overcast days bring better dry fly action

The San Juan's tailwater nature means stable, predictable flows. Unlike freestone rivers, you won't wake up to blown-out conditions. But checking flows helps you understand fish positioning and wading access.


Quick Reference: What to Bring

ItemSize/TypeNotes
Midges#20-28Zebra, RS2, black larva
BWOs#20-24Parachute Adams, Sparkle Dun
San Juan Worms#14-18Red, tan, brown
Tippet5X-7X fluorocarbonLots of it
Leader9-12' 4X-5XLong and fine
Strike indicatorsSmallYarn or micro bobbers

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