Across western Lake Erie, a giant green algal mass is again forming and it’s the largest in three years. How big is it?

So big it can be seen from space and, at 620 square miles, is about bigger than the largest cities in Michigan (Detroit), Ohio (Columbus) and Indiana (Indianapolis) put together.

Not just freakishly huge, the unsightly, globby green mass is prompting beach advisories about swimming in Ohio and Michigan and prompted worries about a repeat of 2014. That’s when toxic algae caused Toledo to shut its water plant, leaving over 500,000 people without running water for nearly three days.

But don’t blame Michigan this time.

Just five years after that dramatic water shutdown, environmentalists and state officials praise Michigan farmers for reducing the algae-feeding nutrients that can run off the land and into the lake.

The efforts of hundreds of farmers in southeast Michigan to filter runoff and limit the loss of phosphorus – used to fertilize crops – have earned them the appreciation of state leaders on both sides of the border.

“The growers care,” said Jim Johnson, director of the environmental stewardship division of the Michigan Department of Agriculture and Rural Development.

Combined with major reductions at Detroit’s biggest wastewater treatment plant, Michigan is well on its way of meeting a goal – set by Michigan, Ohio and Ontario officials – of reducing phosphorus releases into the Lake Erie basin by 40 percent by 2025.

Already, Michigan has reduced phosphorus releases by 36 percent since 2008, the benchmark year. One of the biggest reductions came from the Detroit sewage plant, which empties into the Detroit River that feeds Lake Erie.

And farmers, who contribute an estimated 85 percent of the phosphorus found in the lake, have lowered their discharges by 26 percent, Johnson said.

Despite those reductions, the algae continues to grow in Lake Erie, prompting warnings to avoid contact with the algae.

That’s because the far bigger problem lies in the fertile land in the Maumee River watershed across northwest Ohio and on into Indiana, an area of 4 million acres, 90 percent of it farmland (there are roughly 10 million acres of farmland in all of Michigan).