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Massachusetts · SuAsCo watershed

Concord River
water quality.

Explore the Concord River and learn how public measurements help explain changing conditions across the watershed.

RouteConcord → LowellPublic sourceOARS

What you can explore

Open the interactive Rivistry dashboard to view available measurements, station context, historical charts, reference lines, and recent weekly highlights for Concord River.

Open Concord River dashboard

Read the context

River measurements can vary with season, rainfall, temperature, flow, sampling location, and method. Rivistry presents them as evidence to understand and investigate—not as a standalone safety determination.

For the original monitoring information, visit OARS.

River-specific context

Nutrients, algae, and fish contaminants

The Concord connects the Sudbury and Assabet systems, so nutrient enrichment is an important part of its story. Massachusetts also reports elevated PFAS in fish from the Concord River area.

Watershed connection

Nutrient conditions from the Sudbury and Assabet contribute to the context of the lower Concord River.

Fish-tissue context

A 2024 local environmental-health notice reported elevated PFAS in Concord River fish above the Massachusetts fish action level. This is fish-tissue information, not a claim about every water sample.

Research source: Town of Concord and National Park Service

Keep following changes

Weekly River Updates compare new observations with previous readings, recent baselines, trends, and applicable reference values.

See Weekly River Updates →