Bronx River shows improvement but remains vulnerable to stormwater pollution, advocates say

Daniel Rennell, deputy director of programming at the Bronx River Alliance, said the Bronx River has seen measurable improvements but remains vulnerable to pollution tied to stormwater and sewer infrastructure. "We do see the trash that does end up in the river, but it's not, you know, getting stuck on the sides or it gets cleaned," Rennell said. "There's a big trash boom maintained by the New York City Department of Environmental Protection at Concrete Plant Park."

Rennell also identified combined sewer overflows (CSOs) below East 100th and 82nd Street as sources of pollution during heavy rain. "So when there's a heavy rain, the river is automatically polluted, just like many other waterways in big cities," he said. The guest described the watershed as a boroughwide issue: runoff from impermeable surfaces and broken sewer lines contributes to pollution beyond the immediate river corridor.

Advocates called for expanded green infrastructure — permeable surfaces, trees and soil-based solutions — to reduce runoff and relieve the sewer system. Rennell said those measures reduce the burden on sewers and will "end up with a cleaner river." He pointed to operational responses such as trash booms and volunteer cleanups as interim measures but stressed that long-term investments in infrastructure and cross-jurisdictional coordination are needed.

The interview noted specific agencies and mechanisms (state DEC management of the waterway and NYC Parks and DEP involvement in related park and sanitation work) but did not include a city infrastructure spending commitment in the recording. Rennell encouraged residents to participate in community cleanups and to attend related events like the Bronx River Assembly on March 5.