Hazardous blue-green algae appeared this week for the first time this summer in western Lake Erie, according to the National Oceanic and Atmospheric Administration.
An agency bulletin published late Monday showed that the existing bloom extends from Maumee Bay near Toledo up the lake's western shore into Michigan and then past Cedar Point, Ohio.
A second bloom in Sandusky Bay, which appeared earlier this month, now also extends into Lake Erie, NOAA's bulletin states.
The blooms of toxic microcystis cyanobacteria have become an annual problem on the western side of the lake as mats of thick, pea soupy green scums coat the shorelines, beaches and open lake waters during the mid to late summer.
Typically, wetter than average springs are thought to be the main driver for the persistence and breadth of the summertime blooms.
Rains wash high levels of phosphorous from an agricultural-heavy 4 million acre Maumee Bay watershed into the lake, fueling the blooms.
In early August 2014, a bloom inundated the water system for the city of Toledo, forcing hundreds of thousands of residents onto bottled water for several days.
Earlier this month, federal scientists projected this year's bloom could be one of the top three or four most severe on record.
Although toxic algae is a persistent problem on inland ponds and lakes in New York State and in bays on Lake Ontario, no blooms have been discovered on the state's Lake Erie shore to date.
Blooms have, however, been found at Presque Isle Bay in Erie, Pa., just 90 miles from Buffalo.