The Trust was first established in 1997 by the Māori Land Court after a lengthy legal battle with the Crown. The Trust was established as a Whenua Tōpū Trust. There are ten trustees on the Trust representing the interests of the 10 land blocks surrounding the Lagoon. Of the ten land blocks listed below, the Awapuni block was once a 359 acreblock before it was divided into 2 separate blocks. One (Awapuni) was awarded to Te Aitanga-a-Māhaki hapū and the other (Awapuni No. 1) to Ngāti Kaipoho and Ngai Tawhiri hapū of Rongowhakaata iwi.