How high is the Big Sioux River at Sioux City, IA right now?

The Big Sioux River at Sioux City, IA is currently flowing at 0 cubic feet per second with a gage height of 10.93 feet, based on the most recent USGS instantaneous reading.

Is the Big Sioux River at Sioux City, IA at flood stage?

No — the gage height is 21.07 feet below the NWS flood-stage threshold of 32.0 feet.

What is the historical median flow for the Big Sioux River at Sioux City, IA on October 28?

The long-term median discharge for this date is 1,200 cfs based on USGS daily statistics. The 10th–95th percentile range historically is 352 to unavailable cfs.

Where is the Big Sioux River at Sioux City, IA stream gauge located?

The Big Sioux River at Sioux City, IA stream gauge is operated by the USGS in Woodbury County, IA on the Big Sioux River. USGS site number 06485950 (coordinates 42.5244, -96.4805).

Big Sioux River at Sioux City, IA

USGS Site No: 06485950 • Big Sioux River • Woodbury County, IA

Big Sioux River at Sioux City, IA on the Big Sioux River is currently at 0 cfs (Unknown) . Gage height: 10.93 ft.

Reading from 4 months ago

↑ Upstream on Big Sioux River

Big Sioux River at Akron, IA

CFS Discharge

10.93

Gage Height (ft)

Unknown

Flow Condition

Normal

Flood Status

Historical Percentile Comparison

Today's discharge compared to the long-term record for October 28 at this station. Percentile rank shows what fraction of historical years had lower flow on this date.

Percentile	Label	CFS Threshold
10th	Very Low threshold	352
25th	Low threshold	574
50th (Median)	Normal (median)	1,200
75th	High threshold	3,750
95th	Very High threshold	0

30-Day Hydrograph

Recent discharge plotted against the historical 10th–95th percentile envelope for the same calendar days. Source: USGS daily values + long-term statistics.

10th–95th historical Day-of-year median Recent discharge

30-Day Flow History

Date	Discharge (CFS)	Gage Ht (ft)
May 28, 2026	—	11.15
May 27, 2026	—	10.94
May 26, 2026	—	10.74
May 25, 2026	—	10.65
May 24, 2026	—	10.62
May 23, 2026	—	10.85
May 22, 2026	—	10.84
May 21, 2026	—	10.76
May 20, 2026	—	10.78
May 19, 2026	—	10.70
May 18, 2026	—	10.48
May 17, 2026	—	10.82
May 16, 2026	—	10.11
May 15, 2026	—	10.21
Apr 20, 2026	—	10.24
Apr 19, 2026	—	10.17
Apr 18, 2026	—	10.27
Apr 17, 2026	—	10.28
Apr 16, 2026	—	10.33
Apr 15, 2026	—	10.35
Apr 14, 2026	—	10.37
Apr 13, 2026	—	10.39
Apr 12, 2026	—	10.44
Apr 11, 2026	—	10.40
Apr 10, 2026	—	10.43
Apr 9, 2026	—	10.38
Apr 8, 2026	—	10.40
Apr 7, 2026	—	10.38
Apr 6, 2026	—	10.26
Apr 5, 2026	—	10.40

Station Information

USGS Site No: 06485950
State: IA
County: Woodbury County
Coordinates: 42.5244, -96.4805
Drainage Area: 8,430 mi²
Datum (ft): 1,060.0
HUC Code: 101702032507

View on USGS NWIS →

Flood Stage Thresholds

Action Stage: 29.0 ft
Flood Stage: 32.0 ft
Moderate Flood: 38.0 ft
Major Flood: 41.0 ft

Currently 21.07 ft below flood stage.

Recent Extremes

Max discharge: 2,220 cfs

Jun 3, 2025
Min discharge: 834 cfs

May 11, 2025
Days at flood stage: 0

Computed from the local daily-values archive.

Nearby Gauges

Perry Creek at 38th Street at Sioux City, IA
3.6 mi · 24 cfs

Very High
Missouri River at Sioux City, IA
4.3 mi · 28,400 cfs

Normal
Big Sioux River Near Jefferson, SD
7.3 mi · 1,830 cfs

Normal
Floyd River at James, IA
9.3 mi · 861 cfs

Very High
Perry Creek Near Millnerville, IA
12.9 mi · 3 cfs

Normal