Looking like a giant glob of beer foam, pulp wastes from the Hammermill Paper Co. stained Lake Erie’s Pennsylvania shore. The white mess was penned by a dike built of old tires and oil drums, but residue seeped through to foul open waters.

Written By: Lily Rothman, Liz Ronk

In 1968, two years before the first Earth Day, LIFE magazine dispatched photographer Alfred Eisenstaedt to the Great Lakes to capture a crisis.

“Lake Erie, the smallest and shallowest of the five lakes, is also the filthiest; if every sewage pipe were turned off today, it would take 10 years for nature to purify Erie. Ontario is a repository for Buffalo-area filth. Michigan, where 16 billion small fish, called seawives, mysteriously died last year, is a cul-de-sac without an overflow pipe, and if Michigan becomes further polluted, the damage may take 1,000 years to repair,” the magazine explained. “Huron and Superior are still relatively clean, but they are in danger.”

And, statistics aside, the photographs Eisenstaedt produced told the story in lurid browns, oranges and grays, punctuated by the vivid iridescence of the occasional oil slick. As many in the United States were starting to realize, pollution of the American environment seemed to be reaching a point of no return. From that, there was some hope. “For selfish as well as civic reasons, more has been done in the past three years to clean the lakes than in the preceding 30,” the article reported.

Though federal water-protection laws did exist already (the Federal Water Pollution Control Act was 20 years old at that point) they were only just starting to get teeth, and technology that would facilitate a clean-up was improving. In 1972, the law was revamped as the Clean Water Act, and the newly formed Environmental Protection Agency made the lakes a priority. They still are, just as they are still under threat from a variety of sources. Though progress has been made on some fronts—Lake Erie has come back from the “dead—the words of one teenager who wrote to the Secretary of the Interior in the 1960s, and who was subsequently quoted by LIFE, still read as a warning.

“I was truly amazed,” he remarked upon visiting a polluted lakeshore, “that such a great country should not solve this problem before it’s too late.”

Masses of dirty soapsuds glided down Ohio’s Cuyhoga River. Shimmering in sewage, they were bound for Lake Erie. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

In the Cleveland port, litter was used to build unsightly breakwaters. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

Fred Wittal, shown cleaning a meager perch catch, was the last of the commercial fishermen in his area. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

The Cuyahoga snaked through Cleveland, carrying a load of detergents, sewage and chemicals to Lake Erie. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

This oil melange was waste from U.S. Steel. It is shown on the Grand Calumet River, a Lake Michigan tributary where even worms could no longer survive. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

Another problem was natural pollutants such as the red clay delivered by the Big Iron River in Michigan. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

On the Canadian shore, a slaughterhouse pipe was the best place to try to catch what fish were left. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

The Detroit River flowed into Lake Erie. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

“Beside the deep, clear waters that inspired Longfellow to write “By the shore of Gitche Gumee,” a waterfall of taconite tailings from the Reserve Mining Co.’s plant at Silver Bay, Minn. spilled into Lake Superior at the rate of 20 million tons a year. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

Looking like a giant glob of beer foam, pulp wastes from the Hammermill Paper Co. stained Lake Erie’s Pennsylvania shore. The white mess was penned by a dike built of old tires and oil drums, but residue seeped through to foul open waters. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

In 1968, Lake Erie’s Sterling State Park had been dangerously polluted by septic-tank wastes for eight years, but despite warning signs the state of Michigan still permitted swimming. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

White Lake, a five-mile-long catch basin on Lake Michigan’s eastern shore, was covered by sewage-fed weeds. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

At Green Bay, Wis., paper mill refuse helped turn the municipal beach into a marsh: there had been no swimming there for 25 years. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

The beach at Whiting, Ind., 20 miles from Chicago, had been closed for ten years in 1968; Whiting had a problem in common with other lake communities: it had only one sewer system for human refuse and storm waters. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

Lake Michigan’s big polluters were steel mills and refineries, some of which were clustered along the Indiana Harbor ship Canal, an oily caldron running through East Chicago. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images

A city sewer dumped into a Great Lake. Alfred Eisenstaedt The LIFE Picture Collection/Getty Images