MELISSA BLOCK, HOST:
That pea-soup green water from Lake Erie is a familiar sight to aquatic biologist Jeffrey Reutter. He's been studying algae blooms on Lake Erie and the other Great Lakes since the early 1970s. Reutter now directs the Ohio Sea Grant and Stone Laboratory at Ohio State. Dr. Reutter, welcome to the program.
JEFFREY REUTTER: Thanks for having me.
BLOCK: And why don't you help us understand what makes Lake Erie so sick? What's behind this recent algae bloom that we've been seeing?
REUTTER: We have put too much phosphorus into the lake and that has allowed the algal population to get too large and allowed the wrong kinds of algae to bloom. That's really what's causing the problem right now.
BLOCK: And the phosphorus is coming from where, specifically?
REUTTER: Nowadays, it comes primarily from agricultural runoff. But there's also some coming from sewage treatment plants, septic tanks that are failing, even things we are doing in our own homes, potentially with cleaners. There's a lot of room for all of us to take action. But by far, the biggest source is runoff from farms.
BLOCK: We mentioned that you started the studying Lake Erie back in the early 1970s. And I would be curious to hear about what the lake was like back then. Lake Erie had a reputation as being a dead lake. What did it look like? What did it smell like?
REUTTER: The lake really looked bad in 1971, when I started. I have a picture of my hand in front Stone Lab, in 1971, just completely immersed in algae. It looked like I'd stuck my hand in green paint. To solve that problem, we did a lot of research and a lot of work to understand what was happening in the lake. The primary culprit here was the amount of phosphorus that we were putting in. Exactly the same problem we have today.
BLOCK: But a different source back then?
REUTTER: Exactly, yes. The primary source in those days was poor sewage treatment. And the amount that we had to reduce the load, to solve the problem, was about a two-thirds reduction. It was very large. But we accomplished it by the early 1980s. The lake responded in an unbelievably dramatic way and, literally, the best example in the world of ecosystem recovery. Unfortunately, about the mid-1990s, that great trend that we saw during the '70s and '80s started to turn around. The load of phosphorus started to increase and we're back up right now to where we were in the '70s. The blooms have returned and we're having the kinds of problems that we had in Toledo.
BLOCK: I thought, Dr. Reutter, that the Clean Water Act of 1972 was supposed to fix this. I mean, you say the lake did recover. So what's going on now that you're seeing this again?
REUTTER: It's just that we need to get about a 40 percent reduction to solve this problem. We're trying to modify the behavior of farmers and that's challenging.
BLOCK: And does the Clean Water Act address farming and runoff in any way?
REUTTER: Not with the same level of intensity that it did for sewage treatment plants.
BLOCK: Well, Dr. Reutter, if you're looking for fixes to keep this from happening again, what would they be?
REUTTER: That's a very important question because a lot of people would tend to say we've got to make Toledo do a better job of providing clean water. And Toledo is really doing a miraculous job. And there's a lot of people, at Ohio EPA and U.S. EPA, the mayor, the water treatment plant, that did amazing things over the last few days to get that problem resolved. But the point, I think, really has to be that this problem starts far back up in the watershed. The Maumee River is the largest single tributary to the Great Lakes. And it drains four and a half million acres of agricultural land, extending back to Fort Wayne, Indiana and up into Southern Michigan. There's a lot of people that have to understand that what they do on the land that far from Lake Erie has a very significant impact on the lake. And when that load of phosphorus from the Maumee hits the western basin of Lake Erie, it's a very small, very shallow, very warm basin. It's the perfect recipe to have a harmful algal bloom. It's simply the situation that we had this past Friday and Saturday. The weather literally blew that bloom down to the - right over top of the water intakes for the city of Toledo and they sucked it in.
BLOCK: Jeffrey Reutter head up the Ohio Sea Grant and Stone Lab at Ohio State, where he also directs the Great Lakes Aquatic Ecosystem Research Consortium. Dr. Reutter, thanks so much.
REUTTER: Thank you. Transcript provided by NPR, Copyright NPR.