How high is the Mazon River Near Coal City, IL right now?

The Mazon River Near Coal City, IL is currently flowing at 148 cubic feet per second with a gage height of 1.90 feet, based on the most recent USGS instantaneous reading.

Is the flow on the Mazon River Near Coal City, IL normal for this time of year?

Current flow is classified as normal for June 11. Today's discharge is at the 39th percentile compared to the long-term historical record at this gauge.

Is the Mazon River Near Coal City, IL at flood stage?

No — the gage height is 10.10 feet below the NWS flood-stage threshold of 12.0 feet.

What is the historical median flow for the Mazon River Near Coal City, IL on June 11?

The long-term median discharge for this date is 196 cfs based on USGS daily statistics. The 10th–95th percentile range historically is 30 to 1,540 cfs.

Where is the Mazon River Near Coal City, IL stream gauge located?

The Mazon River Near Coal City, IL stream gauge is operated by the USGS in Grundy County, IL on the Mazon River. USGS site number 05542000 (coordinates 41.2862, -88.3599).

Mazon River Near Coal City, IL

USGS Site No: 05542000 • Mazon River • Grundy County, IL

Mazon River Near Coal City, IL on the Mazon River is currently at 148 cfs (Normal — 39th percentile for this date) . Gage height: 1.90 ft.

Reading from 1 week ago

148

CFS Discharge

1.90

Gage Height (ft)

Normal

Flow Condition

Normal

Flood Status

Historical Percentile Comparison

Today's discharge compared to the long-term record for June 11 at this station. Percentile rank shows what fraction of historical years had lower flow on this date.

Percentile	Label	CFS Threshold	Today's Flow
10th	Very Low threshold	30
25th	Low threshold	83
50th (Median)	Normal (median)	196	Today: 148 cfs
75th	High threshold	349
95th	Very High threshold	1,540

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	178	2.00
May 27, 2026	200	2.08
May 26, 2026	233	2.21
May 25, 2026	246	2.25
May 24, 2026	173	1.98
May 23, 2026	149	1.90
May 22, 2026	143	1.88
May 21, 2026	155	1.92
May 20, 2026	188	2.03
May 19, 2026	213	2.13
May 18, 2026	177	1.99
May 17, 2026	180	2.00
May 16, 2026	185	2.02
May 15, 2026	182	2.01
Apr 20, 2026	1,100	4.15
Apr 19, 2026	1,840	5.18
Apr 18, 2026	1,820	5.15
Apr 17, 2026	1,480	4.72
Apr 16, 2026	1,500	4.72
Apr 15, 2026	838	3.70
Apr 14, 2026	456	2.93
Apr 13, 2026	346	2.66
Apr 12, 2026	371	2.73
Apr 11, 2026	436	2.90
Apr 10, 2026	564	3.18
Apr 9, 2026	741	3.52
Apr 8, 2026	969	3.93
Apr 7, 2026	1,380	4.57
Apr 6, 2026	2,180	5.62
Apr 5, 2026	5,400	9.05

Station Information

USGS Site No: 05542000
State: IL
County: Grundy County
Coordinates: 41.2862, -88.3599
Drainage Area: 455 mi²
Datum (ft): 527.2
HUC Code: 07120005

View on USGS NWIS →

Flood Stage Thresholds

Action Stage: 10.0 ft
Flood Stage: 12.0 ft
Moderate Flood: 16.0 ft
Major Flood: 19.0 ft

Currently 10.10 ft below flood stage.

Recent Extremes

Max discharge: 5,400 cfs

Apr 5, 2026
Min discharge: 0 cfs

Sep 20, 2025
Days at flood stage: 0

Computed from the local daily-values archive.

Nearby Gauges

Illinois River at Morris, IL
5.9 mi · 5,290 cfs

Low
Aux Sable Creek Near Morris, IL
9.1 mi · 35 cfs

Low
Kankakee River Near Wilmington, IL
9.9 mi · 2,570 cfs

Low
Kankakee River at Custer Park, IL
12.4 mi

Unknown
Du Page River at Shorewood, IL
18.5 mi · 171 cfs

Normal