How high is the Green River at Mammoth Cave, KY right now?

The Green River at Mammoth Cave, KY is currently flowing at 2,220 cubic feet per second with a gage height of 13.28 feet, based on the most recent USGS instantaneous reading.

Is the flow on the Green River at Mammoth Cave, KY normal for this time of year?

Current flow is classified as normal for June 11. Today's discharge is at the 68th percentile compared to the long-term historical record at this gauge.

Is the Green River at Mammoth Cave, KY at flood stage?

No — the gage height is 18.72 feet below the NWS flood-stage threshold of 32.0 feet.

What is the historical median flow for the Green River at Mammoth Cave, KY on June 11?

The long-term median discharge for this date is 907 cfs based on USGS daily statistics. The 10th–95th percentile range historically is 380 to 7,070 cfs.

Where is the Green River at Mammoth Cave, KY stream gauge located?

The Green River at Mammoth Cave, KY stream gauge is operated by the USGS in Edmonson County, KY on the Green River. USGS site number 03309000 (coordinates 37.1800, -86.1125).

Green River at Mammoth Cave, KY

USGS Site No: 03309000 • Green River • Edmonson County, KY

Green River at Mammoth Cave, KY on the Green River is currently at 2,220 cfs (Normal — 68th percentile for this date) . Gage height: 13.28 ft.

Reading from 1 week ago

↑ Upstream on Green River

Green River at Munfordville, KY

Downstream on Green River ↓

San Rafael River at Mouth Near Green River, UT

2,220

CFS Discharge

13.28

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	380
25th	Low threshold	646
50th (Median)	Normal (median)	907
75th	High threshold	2,730	Today: 2,220 cfs
95th	Very High threshold	7,070

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	4,110	16.37
May 27, 2026	3,860	15.98
May 26, 2026	2,340	13.49
May 25, 2026	2,950	14.55
May 24, 2026	2,990	14.63
May 23, 2026	1,100	10.96
May 22, 2026	831	10.33
May 21, 2026	485	9.33
May 20, 2026	290	8.71
May 19, 2026	295	8.73
May 18, 2026	305	8.76
May 17, 2026	316	8.80
May 16, 2026	329	8.85
May 15, 2026	345	8.90
Apr 20, 2026	443	9.23
Apr 19, 2026	459	9.28
Apr 18, 2026	474	9.33
Apr 17, 2026	489	9.37
Apr 16, 2026	506	9.43
Apr 15, 2026	521	9.47
Apr 14, 2026	537	9.52
Apr 13, 2026	553	9.57
Apr 12, 2026	572	9.62
Apr 11, 2026	595	9.69
Apr 10, 2026	622	9.76
Apr 9, 2026	667	9.89
Apr 8, 2026	724	10.05
Apr 7, 2026	761	10.15
Apr 6, 2026	747	10.11
Apr 5, 2026	736	10.08

Station Information

USGS Site No: 03309000
State: KY
County: Edmonson County
Coordinates: 37.1800, -86.1125
Drainage Area: 2,020 mi²
Datum (ft): 409.4
HUC Code: 05110001

View on USGS NWIS →

Flood Stage Thresholds

Action Stage: 20.0 ft
Flood Stage: 32.0 ft
Moderate Flood: 57.0 ft
Major Flood: 62.0 ft

Currently 18.72 ft below flood stage.

Recent Extremes

Max discharge: 19,500 cfs

May 18, 2025
Min discharge: 235 cfs

Oct 18, 2025
Days at flood stage: 1

Computed from the local daily-values archive.

Nearby Gauges

Nolin River at Kyrock, KY
10.0 mi · 0 cfs

Unknown
Green River at Munfordville, KY
13.8 mi · 1,570 cfs

Normal
Bacon Creek Near Priceville, KY
14.2 mi · 29 cfs

Normal
Barren River Near Finney, KY
19.7 mi · 400 cfs

Normal
Barren River at Bowling Green, KY
21.5 mi · 778 cfs

Normal