Tiete River victim of a far-reaching, decades-lasting pollution downstream of Sao Paulo, Brazil

Sentinel-2 MSI acquired on 11 August 2015 at 13:18:16 UTC
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Sentinel-2 MSI acquired on 26 July 2016 at 13:12:52 UTC
Sentinel-2 MSI acquired on 05 July 2022 at 13:13:01 UTC
Sentinel-2 MSI acquired on 05 July 2023 at 13:12:49 UTC
Author(s): Sentinel Vision team, VisioTerra, France - svp@visioterra.fr
Keyword(s): River, hydrology, pollution, water colour, water quality, urban planning, infrastructure, Brazil
Fig. 1 - COP-DEM - The source of River Tiete starts 22 km from the sea but only reaches it after flowing 3500 km.
Fig. 2 - S2 (26.07.2016; 05.07.2022; 08.07.2023) - Built along River Tiete, the Metropolitan Region of São Paulo counts close to 20 million people.
The major water challenges in the Metropolitan Region of São Paulo are pollution of drinking water reservoirs that are surrounded by built-up areas including slums, water scarcity and conflicts, inefficient water use, and flooding. Access to water supply and sanitation, as well as service quality for users, are not among the major water challenges.
Fig. 3 - S2 (05.07.2023) - The polluted waters cause a toxic white foam after being stirred by cascades.
As of 2011, 55% of the municipal wastewater in São Paulo is being treated compared to only 20% twenty years earlier.
Fig. 4 - S2 (11.08.2015; 05.07.2022; 05.07.2023) - The Tiete River is biologically dead from São Paulo to Salto, 100 km downstream.
20 years earlier the severe pollution extended 26 km downstream.