Residents of Buenos Aires, Argentina were alarmed to discover that the Sarandí stream had transformed into a startling blood-red color, prompting immediate environmental concerns and investigations by local authorities. The dramatic color change, first reported on February 6, 2025, affected the waterway that runs through the city’s industrial outskirts.
The affected stream, situated approximately 9 miles south of Buenos Aires in the Avellaneda district near Villa Inflamable, flows through an area known for its industrial activities, particularly tanneries that process animal hides into leather using various chemical treatments. The incident quickly gained attention as local residents shared images of the crimson-colored water across social media platforms.
Local resident María Ducomls described the unsettling scene, noting that she first detected strong odors early in the morning. “At 5:30 a.m., we already had a special and hazardous waste incinerator spewing pollutants into the air,” she reported to The Associated Press. Describing the stream’s appearance, she added, “It looks like a stream of blood; we have never seen it like this.”
Officials from Avellaneda suspect the presence of aniline, a toxic compound commonly used in the production of medicines and dyes, might be responsible for the dramatic color change. The incident has prompted authorities to collect water samples and file a formal complaint with the Buenos Aires province Ministry of Infrastructure and Public Services.
The Sarandí stream, which ultimately flows into the Río de la Plata – the major water body between Uruguay and Argentina – has a documented history of similar incidents. Local inhabitants report that the stream has previously displayed various unusual colors, including gray, green, violet, blue, and brown, sometimes accompanied by an oily film on the surface.
These recurring issues have led to numerous complaints against local businesses since the 1990s, with several environmental contamination cases remaining unresolved. The Buenos Aires Province’s environmental ministry has confirmed their response to the recent incident, stating they collected water samples for analysis following reports of the color change.
The environmental challenges facing the region’s waterways extend beyond the Sarandí stream. The nearby Matanza-Riachuelo River basin has earned the notorious distinction of being among Latin America’s most contaminated waterways. This situation has spurred officials to develop infrastructure projects aimed at preventing the discharge of sewage and industrial waste into the basin.
The incident highlights ongoing environmental concerns in the region’s industrial areas, where the balance between economic activity and environmental protection remains a significant challenge. The transformation of the Sarandí stream into a blood-red waterway serves as a stark reminder of the potential environmental impacts of industrial activities and the importance of proper waste management and environmental monitoring.
As investigations continue, local residents and environmental advocates await the results of water quality tests and potential measures to address the contamination. The incident has renewed calls for stricter environmental regulations and better enforcement of existing pollution control measures in the industrial zones
surrounding Buenos Aires.
This latest environmental concern adds to the long-standing issues facing Argentina’s waterways, particularly in areas where industrial development and environmental protection intersect. The outcome of the investigation could have significant implications for both local industries and environmental protection efforts in the region.