Newburyport Conservation Commission Approves Alum Treatment for Cyanobacteria-Plagued Artichoke Reservoir

NEWBURYPORT — March 3, 2026 — Newburyport Conservation Commission unanimously approves alum treatment for city's cyanobacteria-plagued drinking water reservoirs. The commission voted 7-0 Tuesday to issue an order of conditions for an aluminum compound treatment of the upper and lower Artichoke Reservoirs, the city's primary drinking water source, after Water Superintendent Pete King and consultant Laura Beamer reported that six emergency copper sulfate applications in 2025 alone had failed to control saxitoxin-producing cyanobacteria blooms. Beamer said the treatment, planned for the first two weeks of May, should produce a bloom-free 2026 season and provide protection for "at least three more seasons," targeting phosphorus-rich sediments in zones 3A and 3B where blooms were "most persistent" last summer. The commission also voted 7-0 to ratify an emergency certification authorizing the city to dump snow into the Merrimack River during February's storms, with commissioners directing staff to develop a formal best-management-practices protocol for future winter emergencies before next season.