From the resulting scrum Pikiao shifted the ball left, where Raureti Grace beat three tackles with a superb display of strength and footwork to score next to the posts.
Twenty minutes into the game Pikiao had their second try, on the back of a penalty near halfway.
They worked their way into the Ngongotaha 20m before shifting the ball right. Centre Cameron Walters fended off one defender and drew in another before putting Lorne Green over in the corner.
Throughout the first half the Pikiao forwards made good, strong metres up the middle and it wasn't long before they had their third try.
This time it was Green who drew in defenders before returning the favour and offloading to Walters, who was too big and strong to be denied in the corner.
Ngongotaha had periods of possession in good territory but handling errors at crucial times and some epic goal-line defence from Pikiao prevented them capitalising.
With none of the tries converted, Pikiao held a 12-0 lead at halftime.
Pikiao forward Raureti Grace made some rampaging runs against Ngongotaha on Saturday. Photo/Stephen Parker
Pikiao's forwards again rumbled their way up the middle virtually straight from the second-half kick-off.
With the last tackle inside the Ngongotaha 20m, Pikiao put up a bomb to the left wing. Winger Stonie Bartle leapt highest to claim the ball and scored his side's fourth try.
As the ball and the field became wetter and more slippery, play become a little sloppy from both sides but with 20 minutes to go Pikiao centre Noel Te Rangi got the ball 5m from the line and showed great strength to crash over. The try was converted and Pikiao led 24-0.
With 15 minutes to go, on the back of a Pikiao knock-on, Ngongotaha worked their way upfield and finally got on the scoreboard.
The try came from a grubber towards the posts which centre Luke Kingi-Murray showed great desire to chase down and score.
With minutes left on the clock Ngongotaha had their second try as Matiu Weko scored under the posts.
They added a third try after the hooter had blown for fulltime but it was all too little, too late as Pikiao were victors by 24-14.
Pikiao coach Jason Parata said he was pleased to see his players keep their composure throughout the game.
"Our discipline was good, we didn't give away that many penalties and we didn't let them get in our heads - that's been our biggest weakness.
"For the conditions I thought we were pretty good up until the last probably 10 minutes.
"It's a bit disappointing to let three [tries] in but it's good to get the win - with the last try I think the boys heard the hooter and just clocked off.