Population estimates for 2035 and 2060 for communities which would have stations in the ultimate thought (these are just my guesses, and do not include the rural area surrounding which would add more to the populations.) For comparison, I expect the old City of Ottawa to grow very slowly in the time frames, about 0.2% a year on average with some years of very slight negative growth. These assume a village and town-focused growth plan with no expansion of the urban area except in the vicinity of the corridors (I cannot make assumptions for new station areas since the population of those now is zero), although they don't necessarily assume density.
2009 - 2035 - 2060
LINE 1 (also serves north Kanata)
Carp: 1,600 - 3,400 - 6,500
Kinburn: 270 - 600 - 1,400
Galetta: 160 - 400 - 800
Arnprior: 7,500 - 10,500 - 16,700
Renfrew: 7,800 - 8,200 - 9,500
LINE 2 (also serves south Kanata and Stittsville)
Carleton Place: 10,300 - 19,200 - 35,500
Almonte: 5,200 - 6,900 - 9,300
LINE 3 (also serves Barrhaven)
Richmond: 4,600 - 6,300 - 12,200
Smiths Falls: 8,600 - 8,900 - 11,400
Perth: 6,200 - 6,800 - 7,900
LINE 4 (also serves Leitrim)
Greely: 5,200 - 7,400 - 13,500
Osgoode: 2,900 - 3,600 - 7,200
Kemptville: 4,400 - 7,900 - 17,500
Merrickville: 1,200 - 1,400 - 2,600
LINE 5
Russell: 4,100 - 6,900 - 13,500
Embrun: 6,200 - 10,200 - 21,400
LINE 6
Carlsbad Springs: 240 - 500 - 1,300
Vars: 1,100 - 1,800 - 3,200
Limoges: 2,400 - 4,600 - 9,300
Casselman: 3,500 - 5,900 - 10,200
LINE 7 (could also serve Orleans, route undefined)
Cumberland Village: 1,800 - 2,700 - 4,200
Rockland: 9,500 - 16,200 - 32,500
Plantaganet: 1,200 - 1,600 - 2,900
Alfred: 1,400 - 2,000 - 3,500
LINE 8 (also serves Gatineau)
Buckingham: 14,500 - 20,900 - 29,600
Masson: 7,500 - 12,500 - 26,500
Thurso: 2,400 - 3,700 - 5,300
Plaisance: 1,100 - 1,700 - 2,800
Papineauville: 2,200 - 2,800 - 4,000
Montebello: 1,100 - 1,900 - 3,700
LINE 9
Chelsea: 6,500 - 11,400 - 16,500
Wakefield: 1,500 - 2,900 - 5,100