Their idea is that rather than digging a traditional tunnel or highway system to alleviate congestion, Deep Roads can be built by removing the soil to form shallow channel a few meters underground that would serve as a roadbed, then prefabricated pieces built off-site could create the walls and the roof over the road.

This roof surface can then be used for electric vehicles, pedestrian traffic, or other open spaces. As an enclosed space, the vehicle emissions can be extracted, captured, and processed so they don’t contribute to above ground air pollution.
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