Leave spartina grass in the Taruheru alone

John Wells

Opinion

Re: Spraying of Taruheru River spartina grass. 

Please stop this madness — the basis of this work is totally wrong!

Rather than the early 1900s, the spartina grass was planted in the 1950s by community volunteers in collaboration with the Poverty Bay Catchment Board and Gisborne District Council, specifically to trap silt and build up the berms of the river as a prelude to reclaiming part of those berms for public reserve and riverbank walkway use after construction of the Waipaoa River stopbanks.

The Taruheru River used to be an overflow floodway for Waipaoa river flood-flows but since the Waipaoa stopbanks were constructed the Taruheru floodway was no longer needed  for that purpose. The run-off directly into the Taruheru River from the surrounding flats and hills is now very much less than what was previously scouring the river periodically from the Waipaoa River flood-flows.

Recent flooding along the Taruheru River verges has nothing to do with the spartina grass; it is due to backing-up from the Waimata River due to debris clogging the Gladstone Road and Railway bridges downstream of the Waimata/Taruheru confluence.

Clearing the spartina grass will not change that.

The recent attempt to clear the mudflats opposite the Marina boat-ramp was a very costly failure, not to mention the negative environmental effects of machinery use and fossil fuel burning in that escapade.

Again, rather than negative effects on ecosystems, I have seen the spartina grass provide positive habitat development for wading and sea-bird species and recently the arrival of a pair of pukeko in the grass at the end of Grey Street. I have never seen pukeko in an urban environment before, anywhere.

The berm silt build-up intended back in the 1950s has also been achieved and could now be utilised with partial reclamation along the south bank to extend the walkway/cycleway up to the Botanical Gardens, leaving enough of the spartina grass to continue providing the present wetland birdlife habitat.

Do we want months of dying brown growth turning smelly, and then what happens to it before eventually exposing acres of bare mudflats for the foreseeable future? Not me thanks — there are far more pressing things to spend our rates on.

Leave the spartina grass alone — so we can continue to enjoy the greenery and wildlife in the city centre. In my opinion there will be no benefit whatever from this crazy expenditure.

Footnote response from Joanna Noble, GDC Sustainable Futures director

Councils have responsibilities to maintain biodiversity for biosecurity management and river flood management.

We engaged with DoC and there was consultation on the Regional Pest Management Plan (as required by the Biosecurity Act).

Additional context:

DoC has led Spartina eradication projects elsewhere in New Zealand.

See: www.doc.govt.nz/our-work/controlling-spartina/