South Africa’s Impey became the first rider in the event’s 20-year history to claim the title twice in a row.
Having been a teammate of Australia’s Hayman since 2014, Impey used the moment to dedicate his triumph to the 40-year-old, who had ridden professionally for 20 years.
“I want to dedicate the win to him,” Impey said in a team statement. “He’s been a fantastic teammate and many of my victories have come with him.
“To let him go out this way we were going to celebrate his career anyway tonight, but to win the race overall it’ll be a double celebration.”
Hayman described his week as having been an “emotional high”.
“We needed everyone on and every day there was a plan and things to think about.
“Although I was being pulled in a few extra directions than normal, the number one priority was racing and it’s so nice to be able to do that to the death.”
With the tour being the home race for the team on the WorldTour calendar, Impey said the faith he had in his teammates had gone a “long way” towards helping him achieve his goal.
“We saw the boys committed right to the end,” he said. “Yesterday we really dug deep and we took some valuable seconds.”
He added that his stage win earlier this week gave the team “a lot of momentum”.
“We started to believe we had a chance to win the race. The whole team rode great. The guys picked me up during the week.
“Last year I was a lot more ecstatic because I felt like I made a big step [up]. I feel like I am maturing more as a rider, and that’s so exciting.”