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Swift Diamond River near Errol, NH

Stream10.5 mi
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Around here

Around Swift Diamond River

Umbagog National Wildlife Refuge6.7 mi2 mi

Data Source: Recreation.gov · Source: USGS GNIS · Source: Canadian Geographical Names Database (NRCan), Open Government Licence - Canada · Public land: USGS PAD-US

About this river

Swift Diamond River is a 10.5 mile stream near Mahoosuc Outdoors in New Hampshire. Streamflow is measured at the USGS gauge Diamond River near Wentworth Location, NH (site 01052500). The National Hydrography Dataset places it at stream order 4. Reach geometry comes from the USGS National Hydrography Dataset.

Typical flow by month

1941 to 2026

Swift Diamond River typically runs highest in April, at a median 782 cfs, and lowest in September, at 74 cfs. The highest flow on record for any single day is 9,900 cfs, in 1998.

Show the numbers
Typical flow by month at Diamond River near Wentworth Location, NH, in cfs
MonthTypical (cfs)Usual range (cfs)
January11881 to 170
February8865 to 138
March15279 to 297
April782433 to 1,460
May590339 to 1,010
June204119 to 351
July10763 to 190
August7742 to 159
September7443 to 144
October15986 to 314
November228160 to 398
December165117 to 263

Typical is the median of each month’s daily median values, and the usual range runs from the median 25th to the median 75th percentile, across about 85 years of record. Statistics published by the US Geological Survey for Diamond River near Wentworth Location, NH (site 01052500). Conditions on any given day can fall well outside the usual range. Check the current reading before you go.

Made to print

Put Swift Diamond River on your wall

This river section as an art print, drawn over the real terrain with its miles, plus the trails, roads and peaks around it. Pick the colors and the size, and see the finished print before you buy. From $39, shipping included.

Make the posterOrder by December 8 for Christmas delivery.
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Embed this gauge on your site

Paste this snippet anywhere, an outfitter page, a club site, a trip report, to show Swift Diamond River's live streamflow, water level and 7-day trend. It reads the USGS gauge directly, updates itself, and links back here.

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