Nearly one billion Hindus worship the Yamuna River as a goddess. They consider it nearly as sacred as the mighty Ganges, and yet it is dying. The stretch that meanders through New Delhi teems with filth and toxins, and its surface bubbles with thick, white foam. "Visually, it’s beautiful, but when you get close to it, it’s just that horrible smell,” says Zacharie Rabehi. “It smells like shit. Toxic shit, chemical sewage—a bit of sulfur, a bit of human excrement.”

The French photographer never gave the pollution choking New Delhi much thought until last fall, when the smog got so bad the government declared a state of emergency and #MyRightToBreathe trended on Twitter. He spent November biking along the Mahatma Gandhi Road along the Yamuna River, stopping whenever something caught his eye.

It rarely took long. Vast stretches of the Yamuna, which originates high in the Himalayas and flows 855 miles to the Ganges River, are all but dead. Foam covers large swaths of the water, passersby cover their mouths and noses against the stench, yet the river holds a vital place in religious ceremonies. Rabehi saw people bathing near the cremation center Nigambodh Ghat, where mourners scatter their loved ones. “It’s to clean their soul, not their skin,” he says.

The ethereal images in his series Toxic City also document the smog and trash choking the nation's capital. He found couples snapping "smog selfies" at the airport, and sneaked into the 70-acre Ghazipur landfill aboard a trash truck that trundled up a 100-foot mountain of refuse. But the most striking images are on the Yamuna, a dying river that may have just been granted a reprieve. Last month, the High Court in Uttarakhand granted the Yamuna and Ganges rivers the same status as living humans, which means that harming or polluting the waterways is no different than harming a person.

Rabehi captures this harsh reality with an almost delicate air. In one image, a couple stands on a foamy shoreline praying to a goddess that, as Rabehi says, "is choking to death." The court's declaration may not be enough to save her, but it marks a start.