I don't understand why battery trams would be a con, other than price. Compromising in speed? Even with a overhead centenary, there's a limit of how fast trams will be able to go through downtown Ottawa and Gatineau.
Nice Line T2 runs with overhead centenary in the tunnel (3.2 km) and without above ground (8.1 km). It's about as fast as I would expect tramways to run in the central core should the surface option be chosen.
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