Council favoured a public-private partnership in the project while a group called Regina Water Watch pushed for a traditional design, bid and build model.
Although the results of the city's first referendum in 20 years won't be official until Friday, with all the votes counted, the P3 model received 57 per cent support.
Turnout was high, with approximately 49,000 votes cast.
Some voters on their way out of polling stations Wednesday said the issue boiled down to trust.
Bob Stevenson said it didn't make sense to him to go against the council the city elected.
But Brita Lind said she doesn't believe the city has been transparent about the cost of a P3 model.
Mayor Michael Fougere said he was pleased with the amount of feedback residents have provided on this issue.
“This one has captured the interest of the public; lots of calls, people asking detailed questions to make the final decision," he said.