Local Focus: Kaituna Cut on the mend

Maketu estuary re-diversion shows signs of life again. Made with funding from NZ On Air.

Once described as the food bowl of Te Arawa, the health of the Maketū Estuary has been in decline since drainage work was carried out in the 1950s.

But after completing a project to redirect the Kaituna River 12 months ago, the Bay of Plenty Regional Council says the estuary is already showing signs of improvement.

"The gates have finally been opened under the consent obtained for the diversion of the Kaituna River," Stephen Park, senior environmental scientist at the Bay of Plenty Regional Council said.

"It's now flowing around 600 cubic meters per tidal cycle.

"For many years the river's not been flowing at all into the estuary and the estuary's been filling with sand from the bottom end, from the sea. The nutrients have not been exported out so it's been accumulating. Over time there's been a wide range of detrimental effects that have taken place in the estuary in terms of ecological impacts."

Before the recent opening of three additional culverts to further boost the flow of water into the estuary, the signs of life returning were already there.

"We've seen some of the soft sediment start shifting out of the top end of the estuary here," Park said.

"The changes are very significant ecologically and we're tracking that through time so hope to document and show that in a more scientific basis to show what the changes are quantitatively."

Some changes happened quicker than others.

"The currents taking away some of the mud was almost immediate but even I was surprised at how quickly we had the marine life starting to recruit with crabs, particularly the mud crabs coming back, and with that the bird life coming in.

"Some of the very small marine animals like the little sand-hopper type amphipods recruited very, very quickly and with that we saw spoonbills building up numbers."

With the river running at maximum flow, the $16 million project is expected to revitalise the surrounding wetlands.

"With the increase in fresh water at the top end, we're hoping over time we'll see the salt marsh flourish a lot more because of the lower salinity. Unfortunately, I don't think it will ever be back to its former glory."

This isn't the end of the road yet, but the hard work has been done. Park recognises the long fight locals have had to get to this point.

"The local community and iwi… yes, a lot of them have been waiting a long, long time for this to take place.

"It's been a long time coming."

Made with funding from