How high is the Merrimack River below Concord River at Lowell, MA right now?

The Merrimack River below Concord River at Lowell, MA is currently flowing at 7,160 cubic feet per second with a gage height of 44.00 feet, based on the most recent USGS instantaneous reading.

Is the flow on the Merrimack River below Concord River at Lowell, MA normal for this time of year?

Current flow is classified as high for October 28. Today's discharge is at the 75th percentile compared to the long-term historical record at this gauge.

Is the Merrimack River below Concord River at Lowell, MA at flood stage?

No — the gage height is 8.00 feet below the NWS flood-stage threshold of 52.0 feet.

What is the historical median flow for the Merrimack River below Concord River at Lowell, MA on October 28?

The long-term median discharge for this date is 3,980 cfs based on USGS daily statistics. The 10th–95th percentile range historically is 1,670 to 18,100 cfs.

Where is the Merrimack River below Concord River at Lowell, MA stream gauge located?

The Merrimack River below Concord River at Lowell, MA stream gauge is operated by the USGS in Middlesex County, MA on the Merrimack River. USGS site number 01100000 (coordinates 42.6459, -71.2984).

Merrimack River below Concord River at Lowell, MA

USGS Site No: 01100000 • Merrimack River • Middlesex County, MA

Merrimack River below Concord River at Lowell, MA on the Merrimack River is currently at 7,160 cfs (High — 75th percentile for this date) . Gage height: 44.00 ft.

Reading from 4 months ago

↑ Upstream on Merrimack River

Merrimack River near Goffs Falls, Below Manchester, NH

7,160

CFS Discharge

44.00

Gage Height (ft)

High

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	Today's Flow
10th	Very Low threshold	1,670
25th	Low threshold	2,420
50th (Median)	Normal (median)	3,980
75th	High threshold	7,150
95th	Very High threshold	18,100	Today: 7,160 cfs

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	8,890	—
May 27, 2026	10,200	—
May 26, 2026	9,290	—
May 25, 2026	7,120	—
May 24, 2026	6,420	—
May 23, 2026	6,900	—
May 22, 2026	7,860	—
May 21, 2026	9,340	—
May 20, 2026	11,600	—
May 19, 2026	15,200	—
May 18, 2026	21,000	—
May 17, 2026	25,500	—
May 16, 2026	22,600	—
May 15, 2026	11,100	—
Apr 21, 2026	11,900	—
Apr 20, 2026	11,400	—
Apr 19, 2026	13,200	—
Apr 18, 2026	13,700	—
Apr 17, 2026	12,700	—
Apr 16, 2026	12,100	—
Apr 15, 2026	9,610	—
Apr 14, 2026	8,330	—
Apr 13, 2026	8,640	—
Apr 12, 2026	8,830	—
Apr 11, 2026	9,530	—
Apr 10, 2026	10,700	—
Apr 9, 2026	11,800	—
Apr 8, 2026	13,300	—
Apr 7, 2026	15,300	—
Apr 6, 2026	16,000	—

Station Information

USGS Site No: 01100000
State: MA
County: Middlesex County
Coordinates: 42.6459, -71.2984
Drainage Area: 4,635 mi²
Datum (ft): 4.4
HUC Code: 01070006

View on USGS NWIS →

Flood Stage Thresholds

Action Stage: 50.0 ft
Flood Stage: 52.0 ft
Moderate Flood: 54.0 ft
Major Flood: 58.0 ft

Currently 8.00 ft below flood stage.

Recent Extremes

Max discharge: 44,200 cfs

May 11, 2025
Min discharge: 681 cfs

Sep 23, 2025
Days at flood stage: 0

Computed from the local daily-values archive.

Nearby Gauges

Concord River Below River Meadow Brook, at Lowell, MA
0.7 mi · 323 cfs

Normal
Shawsheen River Near Wilmington, MA
6.9 mi · 18 cfs

Normal
Shawsheen River at Balmoral Street at Andover, MA
7.8 mi · 44 cfs

Normal
Nashoba Brook Near Acton, MA
10.7 mi · 15 cfs

Normal
Nashua River at East Pepperell, MA
14.1 mi · 282 cfs

Normal