West Fork San Juan River
Streamflow, conditions and background by watershed segment. Data through November 1, 2026.
Data gaps and disparities
Found automatically in the gauge records behind this river, and notes from a reviewer who checked them against other sources. Gauges need at least 26 weeks of daily data to appear on the Flow tab.
Warnings (2)
- warning: gap W Fk San Juan R At W Fk Campgr Nr Pagosa Spr, CO: 3 gaps of 60+ days inside the record (3,742 days in all). Longest: Oct 1, 1987 to Apr 30, 1997 (3,500 days); Dec 1, 1997 to Mar 31, 1998 (121 days); Dec 1, 1998 to Mar 31, 1999 (121 days).
- warning: gap West Fork San Juan River Near Pagosa Springs, CO: 3 gaps of 60+ days inside the record (12,386 days in all). Longest: Oct 1, 1960 to Sep 30, 1984 (8,766 days); Oct 1, 1987 to Apr 29, 1997 (3,499 days); Dec 1, 1997 to Mar 31, 1998 (121 days).
Context (3)
Show 3 notes
- ended Discontinued gauges: 3 gauges have stopped reporting: Wf San Juan R Ab Borns Lake,Nr Pagosa Spgs, CO (last 1953); West Fork San Juan River Near Pagosa Springs, CO (last 1998); W Fk San Juan R At W Fk Campgr Nr Pagosa Spr, CO (last 1999). Their segments rest on fewer gauges after those years.
- flatline West Fork San Juan River Near Pagosa Springs, CO: 1 run of 30+ days at exactly the same flow: 15.0 cfs for 68 days from Dec 24, 1935. Usually an estimated period (ice, a broken gauge) rather than measured daily flow.
- flatline Wf San Juan R Ab Borns Lake,Nr Pagosa Spgs, CO: 11 runs of 30+ days at exactly the same flow: 11.0 cfs for 74 days from Dec 30, 1942; 8.0 cfs for 34 days from Nov 28, 1939; 8.0 cfs for 31 days from Dec 1, 1937. Usually an estimated period (ice, a broken gauge) rather than measured daily flow.
Values removed (0)
A reading is removed automatically only when it is impossible (for example, a daily mean above the highest flow USGS recorded that water year). Low and zero flows are never removed: rivers here really do dry up.
None.
Gauges
Each row is one physical gauge; "published by" lists every agency copy that was merged into it.
| Gauge | Segment | Published by | First | Last | Weeks |
|---|---|---|---|---|---|
| Wf San Juan R Ab Borns Lake,Nr Pagosa Spgs, CO | Upper San Juan | codwr | 1937-03-29 | 1953-09-21 | 861 |
| W Fk San Juan R At W Fk Campgr Nr Pagosa Spr, CO | Upper San Juan | codwr | 1984-10-01 | 1999-09-20 | 248 |
| West Fork San Juan River Near Pagosa Springs, CO | Upper San Juan | codwr, usgs | 1935-09-30 | 1998-09-21 | 1518 |