Getting to Deca Wakeboard Park will just take around 20 minutes from the heart of the city. Say, maybe around 4 tracks from your iPod playlist.
When taking a cab, instruct manong to take you to Deca Homes in Tacunan, Mintal. You will have 2 options, one would be the route through Ulas and another one through Catalunan Grande.
Option 1 would be ideal if you live near the Ulas area or south of the city. This would be the ideal route when you're intending to ride in the morning as traffic would be less around this time.
The Catalunan Grande route is relatively near as this would be the least taken way to the Deca Wakeboard Park. Especially if you are coming in from the Diversion Road(The road coming and going to the Davao International Airport) and when traveling during rush hour. If you're intending to score some fruits, enjoy some greenery while psyching yourself up with some wicked tracks, this is the route to take.