Floating Biomass

Excessive growth of aquatic plants is a recognized problem in the watershed and particularly in impoundments of the Assabet River. This indicator is only measured in the Assabet River. Floating aquatic biomass includes filamentous green algae, duckweed, and rooted aquatic plants that reach the surface. While it includes water chestnut, that is not a significant component of these calculations due to intensive management efforts in the impoundments. Reduction in aquatic biomass is a key goal for the Assabet as stated in the TMDL prepared by Mass DEP: “For the purpose of this TMDL, a substantial reduction in total biomass of at least 50% from July 1999 values is considered a minimum target for achieving designated uses.”