What is the current flow on Rock River?

Rock River was running 4,300 cubic feet per second as of Aug 1, 2026, 5:45 PM UTC, measured at USGS gauge 05446500. This is a build-time snapshot rather than a live reading — check the USGS gauge directly before relying on it.

What is the water temperature on Rock River?

74.5°F (23.6°C) as of Aug 1, 2026, 6:15 PM UTC, at USGS gauge 05440700. Rock River carries no state trout classification, so the trout-stress thresholds do not apply to it — this is a water temperature measurement, not a fishery judgement.

Rock River

Illinois. Streamflow and water-temperature readings from USGS gauges. Running 4,300 cfs as of Aug 1, 2026, 5:45 PM UTC.

Latest Reading

4,300

cubic feet / second

74.5°F

water temperature (23.6°C)

USGS gauges

Flow measured Aug 1, 2026, 5:45 PM UTC at gauge 05446500. Temperature measured Aug 1, 2026, 6:15 PM UTC at gauge 05440700. These are build-time snapshots, not a live feed — check the USGS gauge before relying on them.

USGS Gauges on Rock River

Gauge	Station	Water temp?
05437500	ROCK RIVER AT ROCKTON, IL	—
05440700	ROCK RIVER AT BYRON, IL	Yes
05442300	ROCK RIVER AT DIXON, IL	—
05443500	ROCK RIVER AT COMO, IL	—
05446500	ROCK RIVER NEAR JOSLIN, IL	Yes

Fly fishing rivers →Illinois lakes →

Conditions: USGS NWIS (public domain).