Overall Health Index
The Sudbury-Assabet-Concord River report card compares 20 indicators of river health to scientifically-derived thresholds. These individual indicators were combined to calculate scores for each of the five values identified by stakeholders—Water Quality, Streamflow, Scenery, Habitat, and Recreation—for the upper and lower segments of each river. The scores for these five values were then combined into an Overall Health score for each river segment. The overall grade for the river system is the average of these six river segment scores, weighted by area.