River Explorer

Rivers in Massachusetts

Community-mapped river reaches across Massachusetts. Length, class, and live USGS flow where a gauge sits on the water.

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Free to browse
USGS-sourced rivers
Open in the app for live flow and tracking

State rankings

Longest River Runs in Massachusetts

River data from the USGS National Hydrography Dataset (public domain). Live flow, where shown, from USGS Water Data.

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