Wanaka Memorial

The Wanaka memorial remembers those who gave their lives from Wanaka and also had a separate plaque for those from the Upper Clutha Region.  Would love to know when and whom unveiled the memorial, does anyone know?  While I was in Wanaka met a lovely gentleman at the top of Mount Iron who had lived in the area all his life.  His father and uncles had all left the area to serve in WW1, he also told me about an interesting book called the "The Waiareka Warriors" ."The story of the military service and sacrifice of the men and women of the Waiareka Valley" by Lindsay Malcolm (an area in North Otago close to Oamaru)  I am still trying to locate the book it sounds right up my street.