Conservation order for Rangitata River welcomed
Water conservation order recommendation for Rangitata River welcomed
The Special Tribunal's recommendation that a water conservation order be granted for the Rangitata River is a significant and useful "line in the gravel" for Canterbury's braided rivers, Forest and Bird says.
"Braided rivers including the Rangitata are rare internationally. Their outstanding landscape, habitat, and recreational values are threatened by a barrage of new irrigation and hydro proposals," Forest and Bird field officer, Eugenie Sage says.
"The Tribunal's recommendations are welcome recognition that the Rangitata has nationally outstanding values and that the river should not be further diminished or manipulated by major new irrigation takes and hydro schemes and an environmentally destructive high dam proposal.
"Three recent irrigation and hydro proposals and resource consent applications would increase by 50 % the amount of water currently taken from the Rangitata. In addition, a proposed 50 metre high dam above the Rangitata Gorge would flood the riverbed for 18 kms upstream with devastating consequences for the outstanding landscape and habitat values of the upper Rangitata and for kayaking and rafting, " Ms Sage said.
"The minimum flow regime recommended by the Special Tribunal is substantially less than that sought by Forest and Bird and the Department of Conservation. It would allow existing abstractions to continue, including the major 30.7 cumec take by the Rangitata Diversion Race and some additional takes."
The Tribunal's draft order if not appealed and if implemented by Environment Minister Marion Hobbs, would prevent any dams on the main-stem of the river.
"Wild undammed rivers such as the Rangitata and its tributaries and their landscape, recreation, and habitat values are priceless. Water conservation orders - the equivalent of national park status for water bodies - are an essential tool to protect those which are nationally outstanding.
"The Tribunal's thorough investigation process and its detailed conclusions highlight the value of the water conservation order process, particularly when Environment Canterbury has yet to develop a statutory water management plan for the Rangitata, " Ms Sage said.
"Irrigators and others have sought to weaken the water conservation order provisions of the Resource Management Act. Marian Hobbs needs to signal that these provisions of the Act are not negotiable and not bow to pressure from business interests."
Notes to media
The Rangitata application is the first water conservation order to be sought under the Resource Management Act 1991. The proposal attracted widespread support with more than 1100 submissions.
A substantial portion of the Rangitata is already diverted for irrigation, power generation, and stock water principally through the Rangitata Diversion Race scheme.
Recent proposals for major new takes include:
· Ruapuna Irrigation have applied for eight cumecs
to irrigate 16,500 ha and generate electricity;
· Rangitata South Irrigation Ltd have applied to take six cumecs to irrigate16,000 ha;
· Ashburton River Irrigation Association have applied to take three cumecs to augment flows in the Ashburton River.
· The Mid Canterbury Irrigation Enhancement Society's proposed high dam above the Rangitata Gorge for hydro generation and irrigation would involve taking an estimated 46 cumecs.
The Rangitata supports over 80 different bird species including high numbers of braided river specialists such as the wrybill plover, black-fronted tern and banded dotterel. These three species and black-billed gulls are only found in New Zealand. They are all threatened with extinction. Wrybills are more abundant on the Rangitata than on any other New Zealand river except the Godley. In 2001 60 % of New Zealand's breeding population of wrybill were found on the upper Rangitata.
Birds such as the wrybill and banded dotterel depend on the shingle beds of Rangitata and other braided rivers to breed. During late spring and summer they nest in shallow depressions or scrapes on the shingle bed. The wrybill, the only bird in the world with a sideways twisted or "wry" bill uses this to probe under stones for food. Species such as black fronted tern skim the river braids for hatching insects and tiny fish.
The Rangitata provides habitat for 18 species of native fish including torrent fish, eels, lamprey and bullies.
Water abstraction changes the habitat on which indigenous birdlife and native fish depend. As the natural flows are reduced, weeds such as broom and willow encroach on the bare gravels and shingle beds which the birds use for nesting and breeding. The weed thickets also provide cover for predators such as feral cats, ferrets, stoats, hedgehogs and rats. The braids of the riverbed which previously isolated the breeding islands dry up, allowing predators to cross into nesting areas. There are fewer shallow braids suitable for wading birds to feed. Native bullies and torrent fish die in cut off stretches of the river where water temperatures rise.
Abstractions for irrigation reduce or "flatten out" the river's natural flow regime. Major floods and storm "freshes" help maintain the braided character of the river with its pattern of gravel bars and channels and resort the river gravels on which invertebrates, fish and birds depend.