Megan Hall: Welcome to Possibly, where we take on huge problems like the future of our planet and break them down into small questions with unexpected answers. I’m Megan Hall.
Today, we’re taking a closer look at the rivers that flow through our cities, and the contaminants that they carry. In today’s episode, we’ll focus on metals in the rivers around our home town of Providence, RI.
We had Sarah Kramer and Leena Mudawi from our Possibly Team look into this.
Sarah Kramer: Hey, Megan!
Leena Mudawi: Hello!
Megan Hall: So, our rivers have metals in them? What kind of metals are we talking about?
Dan Ibarra: So metals can come from a variety of different sources.
Sarah Kramer: That's Dr. Dan Ibarra. He’s a professor of Earth, Environmental, and Planetary Science and Environment and Society here at Brown University.
Leena Mudawi: His lab runs the Urban Water Pollution Project, an initiative meant to understand heavy metal pollution in Providence waterways and soil.
Dan Ibarra: You can have metals coming from what we would call the geologic background, from the dissolution or what we call the weathering of the bedrock in any sort of area. Depending on what that bedrock has, you'll have more or less of a certain type of metal such as lead or zinc or copper or arsenic.
Sarah Kramer: When river water flows along a bedrock, it naturally picks up certain metals out of the rock and carries it along to a local waterway.
Megan Hall: So it’s natural?
Leena Mudawi: Well, not all of it. Dan says metals come from human activity, too.
Dan Ibarra: So those metals can come from a variety of different sources, so from infrastructure, so things like pipes, concrete, you know, roadways. …
Megan Hall: How does this stuff get into the rivers?
Sarah Kramer: When it rains, rainwater will travel down whatever surface it lands on and can transport metals it comes in contact with.
Leena Mudawi: And Providence, which has a long industrial past, has had a lot of metals dumped into the soil over centuries.
Dan Ibarra: We had very large jewelry districts in the Providence area that, because they were making jewelry, they were using a variety of different metals in the jewelry making process. So that's an example of a legacy contaminant. The leaded paint-that's another example of a legacy contaminant.
Megan Hall: Are these metals creating problems in our rivers?
Sarah Kramer: Yes, high levels of metals in the river can make the rivers unsafe to be in and around.
Dan Ibarra: Something like lead, if you were to swim and ingest some of that water, or that water became part of your drinking source, the lead in that water is bad just because it influences the development of your brain and your body.
Megan Hall: So, should we be worried about all this metal in our rivers?
Sarah Kramer: The Environmental Protection Agency recommends that Providence residents stay out of the rivers like the Woonasquatucket and Mosshasuck, especially after large storms, when more metals from the road can drain into the water.
Leena Mudawi: And it’s not a good idea to eat fish or other wildlife from these rivers either.
Sarah Kramer: But walking near the rivers or paddling a canoe is totally safe!
Megan Hall: Okay! Is there anything we can do about this?
Leena Mudawi: Several locations across the state are classified as Superfund Sites by the EPA, meaning they are designated for clean up under federal law. So, Rhode Island already has a lot of clean up going on.
Dan Ibarra: So where there has been very large contaminants of the ground in general, the government has taken care of that. They have done things like put impermeable barriers, totally removed and stripped soil from regions.
Sarah Kramer: Public areas like parks and riverbanks are frequently tested by the government, universities and local organizations to make sure they have safe levels of metals and aren't leaching any into the water.
Megan Hall: But Providence doesn’t have as much manufacturing as it used to. So does that mean this problem is getting better? Or are things like climate change making it worse?
Sarah Kramer: Good question. We’ll talk about that in our next episode.
Megan Hall: Got it! Thanks, Sarah and Leena!
That’s it for today. You can find more information, or ask a question about the way your choices affect our planet, at ask possibly dot org. You can also subscribe to Possibly wherever you get your podcasts or follow us on social media at “ask possibly”
Possibly is a co-production of Brown University's Institute for Environment and Society, Ocean State Media and WBRU.
