He said the work would feature one of Williams' renowned birds, this time a hawk. It would focus on the history of the loop, and the future of Whangarei.
"There are great stories from the Loop, such as one about the fires that were lit in the basin, which would illuminate the skies and provide a safe passing for those rowing back to land."
He said the work would honour and draw inspiration from local hapu and feature Maori motifs with depth, meaning and a focus on resilience and perseverance.
The work would feature plywood cutouts attached to the wall, with acrylic and spray paints.
"It will be intentionally bright too and visible from a distance."
This is the third mural that Williams and Tupaea have collaborated on.
The artists were hoping to start the second mural in June, coinciding with landscaping at the new park.
Last June, Williams and Tupaea launched a colourful mural on a wall of Otaika shopping centre.
WDC landscape architect Tracey Moore said the pair had been chosen for the park murals because of the calibre of inspiring work they had created.
The naming of the child-friendly park was still at the ideas stage.
The riverside amenity between would feature a large sandpit with play equipment, seating and a deck. It would be created with reused, salvaged materials and will have an industrial and marine feel.