Early Saturday morning, residents of Toledo woke up to news of toxins in the city’s tap water and were told by officials not to drink it, or even cook or wash dishes in it. The toxin is linked to harmful algae blooms in Lake Erie, which is the source of drinking water for many communities that line its shores. Shelves were cleaned of bottled water soon after the advisory was in place; hospitals, prisons, and restaurants all scrambled to cope with the situation. The advisory was lifted at 9:30am Monday, but left in its wake a lot of questions. Ideastream’s Anne Glausser is with us to sort out what happened and why.
GANZER: So what’s the latest word on the Toledo drinking water situation?
GLAUSSER: The water is safe—it’s ok to drink from the faucet again. The advisory was lifted early this morning after over 30 different tests—and followup testing--confirmed that the harmful toxin was no longer present in the pipes. Multiple agencies performed these tests, both in Toledo and at labs with the federal and Ohio EPA.
GANZER: What toxin was causing all this trouble, and how’d it get in there?
GLAUSSER: It’s a toxin called microcystin, and it is produced by certain types of blue-green algae. This algae crops up in Lake Erie and can form what’s called “harmful algal blooms.” What happened in Toledo was that winds swept the bloom right down next to the water intake valves and so the toxin got sucked up into the city water supply. Water treatment plants routinely test for and treat this toxin but in this case the microcystin somehow overwhelmed Toledo’s 8-phase treatment process.
GANZER: What does it do to the body?
GLAUSSER: Microcystin is toxic to the liver and can cause nausea and vomiting if ingested. It can also cause skin rashes which made some residents leery of taking showers and that sort of thing. There aren’t any federal standards on microcystin levels in drinking water though the safe level is generally believed to be zero. The World Health Organization says drinking water should contain levels of microcystin no higher than 1 part per billion, which is like a drop of water in an area the size of an Olympic swimming pool. All followup testing in Toledo has now shown microcystin levels to be below this level.
GANZER: 11 million people get drinking water from Erie including us in Northeast Ohio—is this something we should be concerned about cropping up here?
GLAUSSER: Alert for, yes. Overly concerned about? No. Here’s the thing: Toledo sits on the edge of Erie’s western basin. I spoke with Jeff Reutter from the Ohio Sea Grant College Program and Stone Lab at Ohio State University and he says the western basin is so shallow and gets so much urban and agricultural runoff that it is particularly vulnerable to these harmful algal blooms. In this case, it was the perfect storm of bad algae, shallow basin, and winds that blew the toxins right into the drinking water intake valves.
I also spoke with the chief of utility operations at Avon Lake Regional Water about the threat here and he said that typically blooms don’t move this far east. Even so, Avon Lake tests for the presence of this microcystin every day. Not all water treatment plants test this frequently but Ohio EPA does work with plants on a regular basis to help with testing and sampling efforts. And using activated carbon is a standard water treatment protocol for removing ALL types of algae, including the ones that produce the toxins, so this kind of treatment is in place already in water treatment plants along Lake Erie.
GANZER: Has this kind of DO NOT DRINK advisory happened before?
GLAUSSER: Yes it happened last year in Ottawa county’s Carroll Township. In that case, it only affected some 2,000 residents and officials were able to connect the system with another source of clean drinking water, so it didn’t reach a crisis state. But it was a warning bell—and public health officials and others said, “Hey we need to pay attention to this—this algae is a big deal.” And now the situation really climaxed this weekend in Toledo.
As Jeff Reutter points out, situations like these speak to a need to take a more upstream approach to dealing with the algae problem. Here’s Reutter talking about why Lake Erie’s so vulnerable and what to do about it:
REUTTER: We’re the southernmost, the shallowest, the warmest and we get more nutrients and when we put in too many nutrients, we get too much algae and we get the wrong kinds of algae. We need to help water treatment plants deal with the problem of the toxins but to eliminate the algae blooms we need to go back up into the watersheds and keep nutrients on agricultural fields. It’s not acceptable to have them running off into our rivers and streams and lakes.
GLAUSSER: Of course sewage and urban runoff like lawn fertilizer also put nutrients into the lake and drive these blooms, but experts in the field point to agriculture as the primary contributor to these blooms right now.
GANZER: Thanks Anne.
GLAUSSER: Thank you.