The Google sister company promised to transform a dilapidated stretch of the Toronto waterfront into the world's most technologically advanced neighborhood.

Quayside would be outfitted with robotic garbage collection, snow-melting sidewalks and self-driving taxibots. Sensors would capture data on park bench usage, air quality and more, aimed at making the neighborhood more livable.

It was handshakes and smiles all around when Prime Minister Justin Trudeau and officials from Sidewalk Labs gathered here 18 months ago to announce the data-driven city of tomorrow. But internal discord and public criticism are threatening the project.

"I don't think they look so happy now," said Paula Fletcher, a Toronto City Council member. "This big idea isn't going exactly the way it was planned."