March 2026 San Juan River Report

San Juan River Report — March 2026

March on the San Juan is shaping up to be low, technical, and very fishable. The river was averaging 300 cfs out of Navajo Dam as of March 9, and Navajo Reservoir was sitting at 0.999 maf of live storage, about 60% of capacity. Reclamation also reported the reservoir finished February at 78% of average storage for that point in the year, which tells you pretty clearly where things stand. 

The big headline is that the river is scheduled to drop again on March 16, when releases out of Navajo Dam are expected to go to 250 cfs at 8:00 a.m. In Reclamation’s operations update, the agency said the change was tied to the increasing severity of drought and would conserve roughly 1,500 acre-feet of stored water through the rest of March while downstream targets are being met by side inflows. Reclamation’s normal target baseflow through the critical habitat reach is 500 to 1,000 cfs, so 250 is undeniably skinny water by San Juan standards. 

For March on the San Juan, I’d keep it simple:

Quick flies list

• Red larva #20–24
• Zebra midge #18–24
• Foam wing emerger #20–26
• KF emerger #20–24
• Root beer baetis / small BWO nymphs #20–24
• RS2 #20–24
• Eggs #14–18
• Worms #10–14
• Jig leeches in white and black #8–14
• Mops #10–12

What that means for anglers is pretty simple: the river will wade easier, fish will get pushed into more defined buckets and shelves, and clean presentation will matter even more than usual. Midges remain the backbone here year-round, and spring baetis windows are always worth watching when cloud cover shows up. On this river, small bugs, precise drifts, and not doing too much usually beat hero casts and overcomplicated rigs. 

For March, I’d expect nymphing to stay the most consistent game, especially for anglers willing to fish methodically and keep flies in the lower third of the column. Dry-fly opportunities should improve on the right afternoons, especially when weather lines up, but this is not the month to show up expecting easy surface fishing all day. Streamers can absolutely have a pulse in March, but the best windows are still going to be tied to weather, light change, and anglers covering water with intent rather than just blind chucking. Based on the low-flow setup, this month should reward anglers who stay patient more than anglers trying to force it. 

One practical note: New Mexico Highway 511 over Navajo Dam is under a traffic-control closure through May 20, with alternating one-way traffic in place, so give yourself a little extra time getting in and out.