Opiki is a small rural settlement in the Horowhenua district of New Zealand's North Island. It is located on the floodplain of the Manawatu River, 15 km southwest of Palmerston North. Opiki and its surrounds had a population of 522 at the 2013 New Zealand census, an increase of 3 people since the 2006 census. There were 264 males and 261 femal…Opiki is a small rural settlement in the Horowhenua district of New Zealand's North Island. It is located on the floodplain of the Manawatu River, 15 km southwest of Palmerston North. Opiki and its surrounds had a population of 522 at the 2013 New Zealand census, an increase of 3 people since the 2006 census. There were 264 males and 261 females. Figures have been rounded and may not add up to totals. 92.6% were European/Pākehā, 7.4% were Māori, 2.5% were Pacific peoples and 3.1% were Asian.