While I often point to Lake Erie’s harmful algae blooms in this blog, the events are increasing nationwide from Minnesota to Florida, where last weekend health departments in some Gulf Coast communities warned beachgoers not to swim. It’s a growing national problem that spells long-term bad news for the boating industry.

It’s upsetting to see the summer harmful algae blooms turn Lake Erie’s precious waters slime green again. This summer’s HABs are covering a significant portion of the western lake, including the islands that are so popular with boaters and anglers, according to the National Oceanic and Atmospheric Administration’s tracking of Microcystis cyanobacteria blooms. But the real shocker comes from a report by the Environmental Working Group that it’s large, unpermitted animal farms in Indiana, Michigan and Ohio that could be causing most of this nutrient pollution.

In Indiana, for example, if you have at least 300 cows, 600 pigs or 30,000 chickens you must have a state permit to manage the manure they produce. But an EWG study estimates that the overwhelming majority of nitrogen- and phosphorus-laden manure that triggers HABs makes its way into Lake Erie from operations that don’t have enough livestock to require a permit. It means no one is tracking where all that manure goes.

Of course, the Hoosier State doesn’t even border Lake Erie. However, its farmland is part of the Maumee River basin, which ultimately feeds Lake Erie at Toledo. Many of the basin’s animal-agriculture hot spots are miles away from the lake, but nutrient runoff from manure spread on crop fields gets into streams and rivers and makes its way downstream, posing a risk to the millions of people who rely on Lake Erie for boating, fishing and drinking water.

Moreover, the runoff increases with above-average spring rains that many experts predict will continue as the climate crisis accelerates.

“More needs to be done to monitor these unpermitted AFOs [animal feeding operations] that are smaller but actually produce most of the manure phosphorus in the basin,” says Anne Schechinger, EWG’s Midwest director. “Indiana does have stricter permitting requirements than Michigan and Ohio. Even so, a whopping 78 percent of animal feeding operations in Indiana’s portion of the Lake Erie basin don’t have permits.”

The EWG report further states that manure from these AFOs normally is spread on cropland nearby. But in places with multiple animal farms, the land can’t hold all of that manure, which then ends up in runoff that pollutes waterways.

The EWG analysis has mapped more than 2,500 animal feeding operations in the western Lake Erie basin encompassing nearly 6 million acres that drain into the lake. They house an estimated 400,000 cows, 1.8 million hogs and nearly 24 million chickens and turkeys.

Until now, no one had known where all the facilities in the basin were located or what’s happening to the manure they produce. That’s because states and the federal government only track the largest factory farms, known as confined animal feeding operations, that require a permit to be built. Operations falling below a threshold aren’t required to get state or federal permits, and their owners don’t need to account for the waste their animals produce or where it goes.

EWG found more than 2,200 unpermitted facilities, or 90 percent of all animal operations in the watershed. And although these operations are smaller than the permitted CAFOs, it’s believed they collectively produce most of the manure that runs into the lake.

To be sure, farm fields don’t just get phosphorus from manure spreading. Commercial fertilizer containing phosphorus is also applied, posing an even greater risk than manure alone.

It’s time to call for the federal and state agencies do their jobs and initiate enforceable programs (backed by legislation) that require a comprehensive analysis of nutrient inputs and licensing for future animal operations. This should include a management plan to control the amount and handling of manure produced from all animal operations.