A bag bulging with trash fell from the garbage truck and a sanitation worker watched as it tumbled into the canal. He shrugged.
"It's already disgusting," he said. "Welcome to Ecatepec."
Tiny rectangle homes patched together with concrete and tin cover the nearby hills and most days the local radio stations broadcast a warning: High-alert for armed robberies.
One of the most crowded, impoverished and violent parts of the country, Ecatepec — a bedroom community of Mexico City — is home to nearly 2 million people.
Located in the state of Mexico, which Enrique Peña Nieto governed before his presidency, Ecatepec registers one of highest rates of killings and disappearances of women in the country. In July, Mexico's Secretariat of the Interior declared an alert in the state of Mexico, specifically highlighting Ecatepec.
"This place is terrifying," said Guadalupe Reyes, whose 18-year-old daughter disappeared from Ecatepec in 2014. "If you're talking about people on the margins, that's us."
Pope Francis has vowed to give voice to the downtrodden during his trip to Mexico and many in Ecatepec, where the pontiff will visit Sunday, say he's picked the perfect place. Others poked fun at Ecatepec's reputation, posting pictures online of the pope gasping and describing it as the moment he found out he'd visit Ecatepec.
Dulce Padilla, 24, who works at a tarot card shop along the pope mobile's route, said she has mixed feelings about the visit.
Trees trimmed, dividing lines painted onto the streets, weeds pulled — she knows the expenses must be adding up.
The pope's visit, according to Gov. Eruviel Ávila, will cost the state more than $520,000, including $140,000 for a high-tech vehicle christened the "Papa ambulancia."
"There are so many people dying of hunger here, or freezing to death, and we're throwing money at this?" Padilla said. "It's great that the pope is coming, but he should see Ecatepec as it is: Ugly. Not dressed in a temporary costume."
Back at the edge of the city — near the dirty canal — a gust of wind whipped plastic bags through the air. The smell of sewage and burning diesel mixed with sizzling carne asada. A taxi driver yanked his steering wheel to miss a mangy, tan dog and another driver swerved around a huge pothole.
A billboard nearby showed a teenage girl with big, sad eyes.
"Have you seen me?" it read, offering a reward for any information on her disappearance.
A different teenager — Reyes' 18-year-old daughter, Mariana Yáñez Reyes — disappeared on a Wednesday evening in September 2014.
She had just turned 18 and planned to start college in a month. She left to make photocopies for a scholarship application and never returned.
Not long after her disappearance, her mother got a phone call from someone identifying themselves as a member of the Familia Michoacána drug cartel. They asked for roughly $25,000 and hung up. Reyes never spoke to them again.
After reporting her daughter missing, Reyes said local authorities did little but ask questions that felt accusatory: Was Mariana a difficult kid? Did she drink a lot?
Then, a few months later, officials called saying they'd pulled Mariana's remains from one of Ecatepec's many trash-clogged waterways. It's called River of the Remedies.
They took a DNA sample from Reyes and said it was a close match to the cadaver. But other than that, Reyes said, they offered no proof — no pictures.
"The investigation isn't even really an investigation," Reyes said.
Her mind still runs fresh with memories of her daughter. The girl with dark, straight hair and a small smile. The one who sang in the church choir and loved to play flag football.
Sometimes Reyes considers leaving Ecatepec. She can't afford it, though.
And some small part of her still thinks the authorities were wrong and, one day, Mariana will come home.
MORE ON POPE FRANCIS