Jeremy Webber and Sean Stults looked like fishermen on Eagle Creek Reservoir as they anchored their small boat in a deep spot on the 1,400-acre lake early Tuesday.
Instead of catching fish, they were capturing data.
The scientists were testing the water for indicators of harmful blue-green algae – the tiny creatures that wreaked havoc with Toledo’s water supply last weekend when they morphed into a toxic algal bloom.
Unlike the fluorescent green slime that could be seen floating on Lake Erie, Toledo’s sole drinking-water source, Eagle Creek Reservoir was a nice shimmering blue. But as the men were sampling the water to monitor changes in algae populations, the potential for danger lurked beneath the surface.
“When you get enough nutrients in the water, they just gorge themselves,” Stults said of algae. “Then they keep replicating and replicating and replicating.”
If not treated in time, the rapid increase in the density of certain blue-green algae can lead to a toxic bloom.
Stults and Webber are part of a team of researchers from the Center on Earth and Environmental Science at Indiana University-Purdue University Indianapolis. The team has routinely tested the reservoir since 2009, now in a partnership with Citizens Energy Group, the utility that runs Indianapolis’s water system.
In early July, their IUPUI colleague Nico Clercin detected an algal bloom in the reservoir, which was quickly treated with an algaecide. The discovery didn’t lead to a crisis such as the one in Toledo, in part because Indianapolis draws water from multiple sources. In case of a problem at one site, the utility can switch to another source.
But the scientists say warding off algae is a long-term problem that plagues bodies of water around the globe. As in the case of Lake Erie, the toxins’ suspected cause is nitrogen and phosphorus, which come from runoff from over-fertilized lawns and farms, and from malfunctioning septic systems and livestock pens.
Greg Druschel, an IUPUI environmental scientist and expert in algal blooms, said the magnitude of Toledo’s problem was a “rare event.”
“But there are a lot of bodies of water around the world that are sick,” he said.
On the morning that Webber and Stults visited Eagle Creek, scientists with the state Department of Natural Resources were testing algae levels in reservoirs on state property to determine if they were safe for swimming.
The department issues an advisory if the concentration of the microcystin toxin, caused by algae, reaches a certain level (6 parts per billion), and it then cautions patrons to shower after swimming and to keep pets out of the water. If toxins reach 20 parts per billion, the department shuts down beaches.
Ingesting water with high algae levels can make humans and animals sick. Exposure to the cyanotoxins produced by the algae can cause rashes, vomiting, nausea, numbness, dizziness and worse, said Max Moreno, a researcher with IUPUI’s Fairbanks School of Public Health.
State Department of Natural Resources scientists, working with the Department of Environmental Management, have been testing water at 13 sites for the past three summers. Two years ago, two dogs died within hours after their owners unknowingly let them play in the algae-tainted Salamonie Reservoir. The couple’s two other dogs were treated for liver damage.
Currently warnings are posted about algae exposure at five state lakes. More may come as the summer heats up.
While state officials advise showering after a swim in an algae-infested lake, the fix for drinking water isn’t so easy, Moreno said. Toledo residents were warned against boiling their drinking water, because doing so just concentrates the toxins.
“It’s bad what happened to the people of Toledo,” Moreno said. “But if serves an alert that this can happen in other places, there may be something good that comes out of it.”
In Indiana, some legislators have expressed concerns that algae warnings can torpedo tourism. They’ve pushed for more monitoring of the state’s public lakes and reservoirs, and they’ve lobbied fellow lawmakers to limit products that contain nutrients that fuel algae growth.
Those efforts haven’t been successful, but lawmakers are expected to study the issue of a statewide water management plan later this year. Among the challenges they face is the fact that guidelines exist about algae levels in drinking water, but state and federal officials do not have clear regulations on what’s considered an acceptable level for algae toxins in recreational waters.
State officials urge residents to do what they can to curb runoff of nutrients that feed algae, including cutting back on lawn fertilizer. But they also warn the problem is complex and won’t quickly go away, even if the watersheds that drain into Indiana’s lakes were cleared of algae-feeding nutrients.
Pat Carroll, head of water quality for the state Department of Environmental Management, described the algae as “very adaptable.”
“They always seem to be one step ahead of us,” he said.
Maureen Hayden covers the Statehouse for the CNHI newspapers in Indiana. She can be reached at email@example.com. Follow her on Twitter @MaureenHayden.