Van Dam began the day as joint leader on 11 under and duelled with defending champion Jiyai Shin through the back nine before picking up four shots in the final four holes with a final round of six under 65.
Katja Pogacar from Slovenia, the other overnight leader, also came home strongly with two birdies in the final four holes to finish 14-under par, one ahead of Shin and all alone second place.
Van Dam said after shooting eight under in the second round to put her in contention, she knew she had to go to another level to win the championship.
“It gave me so much confidence that I knew I could birdie every hole here. I just had to stay patient, trust my long game and I was really happy with the way I putted.”
The day began with a group of five players separated by just two shots at the top of the leaderboard and while Van Dam led at the halfway mark by one shot, Shin and Carly Booth (Scotland) and Madelene Sagstrom (Sweden) were all within striking distance.
Shin looked the most threatening having moved to 12 under and she then drew level with Van Dam at the 12th, only to lose the lead the next hole with a bogey five.
But the defending champion refused to surrender her title and again drew level with a birdie on 15.
Just when it looked like the championship was shifting, the long-hitting Van Dam reached the 15th in two and then holed the eagle putt to move to 15 under.
Shin continued to stake a claim for the title when she birdied 16 to be one shot behind Van Dam.
The Korean bogeyed 17 and Van Dam seized the advantage with birdie on the 16th and then crowned her victory with another birdie on 18 to finish on 17 under (196).
The ActewAGL Canberra Classic is Van Dam’s fourth title on the European Tour.
“I’ve hit a lot of golf balls over the past couple of months and, with my coach Dave, we’ve been working on my swing, so I’m really happy with it right now.”
Katja Pogacar surged home with a final round of 68 to claim second place, her best finish on the Ladies European Tour.
“It was my first time playing in the last group in front of a large gallery, which was different and a great experience…and I loved it.
“I’m so happy to have performed under the pressure. It was a little shaky in the beginning but I finished strongly…which will give me a lot of confidence for the whole season.”
The next event on the ALPG Tour is the Worrells New South Wales Womens Open at Queanbeyan GC just 20 minutes from the venue of this week’s tournament at Royal Canberra Golf Club.
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