There's no info (yet) for how the Sto will operate in Downtown Hull/Ottawa.
However this is my guess on the Sto detours
From Prom du Portage right on Laval , Right Rue Laurier , Left Booth, Left Albert/Slater follow Slater to Rideau Centre.
From Rideau , Left Waller , Right on Mackenzie King Bridge follow Slater to Booth right Booth to Rue Laurier right, Rue Laurier, Left Laval Left Prom Du Portage to route,
The Downtown detours will only be in effect for the 21st as the extra loop is a 1 Day event.
With the Normal Bike day detours in effect (unless Bike Sunday is canceled on a givin weekend ) till the fall.