Alphabet Inc.'s smart city subsidiary released details of its most high-profile project yet, and they have raised eyebrows.

Sidewalk Labs, part of Google's parent company, was awarded development rights for a 12-acre parcel on Toronto's Eastern Waterfront in 2017 and publicized its plans on Feb. 19 after the Toronto Star leaked the details a week prior, Fast Company reports. The project, to be called Quayside, would include 12 buildings constructed from mass timber standing up to 30 stories tall.

Quayside would be home to Google's next Toronto headquarters, as well as 3,000 residential units, a third of which would be affordable. The proposed buildings would leave the timber exposed, with a focus on tenants interacting with the outside — even in winter, thanks to certain weatherproofing techniques Sidewalk Labs plans to integrate. Some buildings would have transparent tarp overhangs to shield the public space between them from the elements, and bike lanes would be heated from beneath the ground.

True to form, Sidewalk Labs' proposal focuses on smart technology and environmental sustainability, claiming that the entire project would be solar-powered, geothermally heated and with state-of-the-art heat and water recycling technology. Trash collection and last-mile delivery would be carried through underground tunnels staffed by robots to keep trucks off the street. The whole complex would be connected to 5G internet and have data collection hardwired into the buildings and the streets.

Some locals have criticized the timber plan, citing the difficulty in preserving wood over a long period of time, especially through hard Canadian winters. Among Sidewalk Labs' plans to address such concerns is the promise to utilize modular construction methods for all of the buildings, improving the efficiency of construction and potentially the ease of maintenance.

Also arousing local suspicion is Sidewalk Labs' use of Heatherwick Studios for design. Heatherwick was the architect for London's failed Garden Bridge, which was proposed by actress Joanna Lumley to be a tribute to Princess Diana. The city scuttled it in 2017. Among the fatal flaws in the project were Heatherwick's design (which some called a misinterpretation of sustainable concepts), the process by which Heatherwick was awarded the design contract and the developer's intent to retain private control over an ostensibly public thoroughfare, according to TreeHugger.

Sidewalk Labs plans to pay the cost of construction, but the infrastructure it requires is estimated to cost as much as $6B. Sidewalk Labs has proposed a deal akin to a Tax Increment Financing district, wherein it would pay the cost up front as a loan and be paid back by the city of Toronto by diverting new property taxes generated by the development.

Because the Star's leak rushed the announcement timeline, Alphabet has yet to finalize these plans, nor has it received approval from district organization Waterfront Toronto or the city. But if it moves forward, the project could be the start of a 350-acre series of projects up and down the waterfront, for which Sidewalk Labs said it would outsource the development.