"Climate change is contributing to electric-green algae blooms. Massachusetts wants a cleanup of the antiquated septic systems feeding the mess, but it could cost billions."

"MASHPEE, Mass. — Ashley K. Fisher walked to the edge of the boat, pulled on a pair of thick black waders, and jumped into the river to search for the dead.

She soon found them: the encrusted remains of ribbed mussels, choked in gray-black goo that smelled like garbage and felt like mayonnaise. The muck on the bottom of the Mashpee River gets deeper every year, suffocating what grows there. It came up to Ms. Fisher’s waist. She struggled to free herself and climb back aboard.

“I did not think I was going to sink down that far,” said Ms. Fisher, Mashpee’s director of natural resources, laughing. Her officers once had to yank a stranded resident out of the gunk by tying him to a motorboat and opening the throttle.

The muck is what becomes of the poisonous algae that is taking over more of Cape Cod’s rivers and bays each summer."

Christopher Flavelle reports for the New York Times with photographs by Sophie Park January 1, 2023. [2]