OARS' "Water Chestnut Management Guidance & Five-Year Management Plan for the Sudbury, Assabet, and Concord River Watershed" (2017) compiles the most recent research on the lifecycle and control of water chestnut, provides guidance on permitting of control efforts (for both permittees and Conservation Commissions), and lays out a management plan for the Sudbury, Assabet, and Concord Rivers. You can download the Guidance, Appendices, and a presentation on the management plan here.