Fly fishing report · Southwest

San Juan River

A below-Navajo-Dam San Juan report for Quality Water trout, technical midge fishing, release checks, access, regulations, and trip planning.

Check flow & weather

Today's river scoreHigh source confidence

Good

Best option: Bank / edge.

Bank and edge fishing remains a practical low-commitment option if access is legal and footing is safe.

Updated Jul 13, 11:17 PM UTCUsually refreshes about every 45 minutes

Recommended approachBank / edge

Mode scores adjust the river-wide score for the risks of wading, bank fishing, or floating.

WadeCheck

This report does not describe this as a primary mode. Verify legal access, depth, launches, and retreat options before planning around it.

Bank / edge · Best fit71/100

Bank and edge fishing remains a practical low-commitment option if access is legal and footing is safe.

Float71/100

A float is in play where this report supports boat access and wind, releases, and shuttle logistics are manageable.

Confirm before you leave

Flow and weather right now.

Use the flow trend to confirm the score before you leave. Weather can change the safest and most productive fishing window.

River strategy

Expect technical tailwater fishing, not easy trout.

The San Juan below Navajo Dam is one of New Mexico's best-known trout tailwaters. It rewards flow checks, small flies, long drifts, and careful handling more than blind casting.

Use the Archuleta gauge and release context before choosing a wade or boat plan.
Quality Water rules and tackle limits matter, so check the current New Mexico rule book.
Start with midges and BWOs, then adjust to fish behavior and water clarity.
Crowds are part of the fishery; have a section, timing, and etiquette plan before arriving.

Why this score moved

FlowUse caution

USGS shows 996 cfs with a stable over about 6 hours trend. same-date USGS history (1963-2023, 61 readings) puts normal around 638 cfs and the upper quartile near 928 cfs; today's flow is high for the date. Fishable water may exist, but do not rate it highly without a safe access, clarity, and wading or boat plan.

Short-term weatherUse caution

The forecast has storm or heavy-precipitation risk, so timing and access matter more than the score alone.

SeasonHelps score

Summer: Cold releases keep trout options open, but crowds and weeds can matter.

Water temperatureHelps score

USGS water temperature is about 53F, with no heat stop triggered.

Public alertsHelps score

No active NWS alert was returned for this forecast point.

Read the water

What changes the plan.

The San Juan can fish year-round because Navajo Dam releases cold water, but flows, pressure, weeds, and weather decide the best tactic. Slow down, fish lighter, and change depth before changing every fly in the box.

Stable release

Fish long midge or BWO drifts, adjust depth, and work feeding lanes patiently.

Higher release

Use heavier rigs, protected edges, and avoid unsafe crossings.

Low clear water

Use smaller flies, lighter tippet, and longer leaders with clean presentations.

Weedy water

Clean flies often and fish lanes where rigs can drift without fouling.

Field plan

Fish it with intention.

Best flows

Use RiverReports Archuleta and USGS 09355500 as the primary release trend, then compare current Navajo Dam and state-park context before choosing a wade depth or boat day.

When to skip

Skip exposed wading when releases rise, weeds make footing and drifts poor, winter weather adds ice risk, or the Quality Water rule and access boundary are not clear.

Local plan

Start with the Archuleta gauge, NMDGF rules, and Navajo Lake State Park notices. Pick one access area, rig small midge/BWO options, and carry a backup plan for crowds.

Backup water

If the San Juan is crowded, weedy, or release-complicated, compare the Chama, Pecos, or Cimarron reports before forcing a technical tailwater day.

Hatches & flies

Bring a flexible box.

TimingWhat to watchUseful flies

March to AprilMidges, BWOs, early caddis, and small stonefliesZebra midge, RS2, BWO emerger, caddis pupa, small black stonefly

Reviewed pattern · report says “Zebra midge”Zebra MidgeLook for a very slim tapered thread body, evenly spaced contrasting wire rib, a small bead, and no tail or wing. The reviewed classic is black with silver wire and a silver bead. Red, olive, brown, glass-bead, jig-hook, resin-coated, or tailed forms must remain labeled variations rather than replacing the classic identity.See photos & how to fish it

Reviewed pattern · report says “RS2”RS2Start with the beadless architecture: two dark-dun Microfibett tails separated behind a slim, tightly twisted and visibly segmented dubbed abdomen; a fuller thorax; and saddle-hackle web clipped into a short angled wing bud. Rim Chung's original-style form uses natural beaver dubbing and hackle web. CDC- or Antron-wing ties, beads, curved hooks, flash, and tailless Avatar-style flies must remain labeled variations.See photos & how to fish it + 3 more reviewed guides in the Fly Box

May to JuneCaddis, PMDs, yellow sallies, golden stones, and runoff-edge bugsElk hair caddis, PMD emerger, yellow sally, Pat's rubber legs, hare's ear

Reviewed pattern · report says “Elk hair caddis”Elk Hair CaddisLook for a tented elk- or deer-hair wing, clipped hair head, dubbed body, rib, and hackle palmered along the body. The body color should be labeled because tiers often match different natural caddis colors.See photos & how to fish it

Reviewed family · report says “PMD emerger”Pale Morning Dun PatternsPMD names an insect group, not one fly. Pale nymphs, trailing-shuck emergers, upright or low-riding duns, cripples, and spent-wing spinners stay visibly separate.See family guide + 3 more reviewed guides in the Fly Box

July to SeptemberTerrestrials, caddis, tricos, midges, and small mayfliesFoam ant, beetle, hopper-dropper, trico spinner, parachute Adams

Reviewed family · report says “Foam ant”Ant PatternsAnt patterns can be foam, fur-bodied, winged, or sunken. The narrow waist and paired body lobes matter more than one material recipe.See family guide

Reviewed family · report says “beetle”Beetle PatternsBeetle flies range from simple foam shells to hair-bodied and sunken forms. A rounded back and compact profile distinguish the family from ants and hoppers.See family guide + 2 more reviewed guides in the Fly Box

October to winterMidges, BWOs, eggs where legal, leeches, and low-light streamer windowsMidge pupa, BWO, egg pattern where legal, leech, small sculpin

Reviewed family · report says “Midge pupa”Midge Patterns by StageMidge wording can mean a threadlike larva, wing-padded pupa, film emerger, tiny adult, or visible cluster. Those profiles fish at different depths.See family guide

Reviewed family · report says “BWO”Blue-Winged Olive PatternsBWO describes a hatch group, not one fly. Nymph, emerger, dry, cripple, and spinner profiles must stay separate because they occupy different parts of the water column.See family guide + 3 more reviewed guides in the Fly Box

Start with a two-fly midge or BWO rig when rules allow, then adjust depth before changing patterns.

Use small indicators, long drifts, and careful mends through slow slicks and flats.

Fish streamers or leeches in low light, on edges, or when releases add movement.

Watch other anglers' spacing and avoid stepping into active feeding lanes.

Carry a thermometer and landing net even though the tailwater is cold; quick handling still matters.

Access & responsibility

Know the entry. Know the exit.

New Mexico lists the San Juan below Navajo Dam as Special Trout Water with Quality Water rules and tackle limits. Check the current NMDGF rule book and state park notices before fishing.

Navajo Dam and Quality Water

Primary special-regulation tailwater focus for this report.

Texas Hole and Flats context

Well-known tailwater areas where crowds, drift quality, and etiquette matter.

Crusher Hole and lower access

Use current state park and NMDGF information before choosing a lower reach.

Transparent sources

Check the facts behind the plan.

Last material review: 2026-05-31

flowRiverReports San Juan River near Archuleta flowUSGS San Juan River near Archuleta 09355500 regulationNew Mexico 2026-2027 Fishing Rules and Information regulationNew Mexico general fishing regulations accessNavajo Lake State Park backgroundNMDGF fisheries management: San Juan River accessNMDGF San Juan Fishing Easement WMA map safetyNational Weather Service forecast point

Common questions

Before you leave.

What should I check first before fishing the San Juan River?+

Check the Navajo Dam release, Archuleta gauge, Quality Water rules, state park notices, and the NWS forecast.

Are there special regulations on the San Juan River?+

Yes. The Quality Water and Special Trout Water rules are central to fishing this river legally.

What flies should I bring for the San Juan River?+

Bring the hatch-chart flies, a small nymph box, and a few streamers. Then adjust for water temperature, clarity, pressure, and the insects or baitfish you actually see.

Can I wade the San Juan River?+

Yes in many tailwater areas, but releases, weeds, and cold water make conservative wading important.

When should I skip the San Juan River?+

Skip it when flows are unsafe, water is too warm for trout, emergency closures are active, or legal access for the reach is not clear.