A collaborative effort has cleaned up a water way:
A South Canterbury stream once written off as a trout fishery because of dairy farming is again attracting anglers, thanks to the efforts of farmers and the community to keep stock out and replant the stream banks.
Before intensive irrigated dairy farming arrived, the Waikakahi Stream was something of a local anglers’ secret, far less known than the nearby Waitaki, but renowned for the quality of its trout.
“They were reported to be ‘the best fish in the country’ and they had a particularly dark orange flesh supposedly because of the freshwater crayfish (koura) that they preyed upon,” said Fish and Game officer Graeme Hughes.
But that changed, Hughes said, about a decade ago when suddenly the koura disappeared and trout numbers plummeted.
“What brought it to our attention was a farmer wintered his cows in there without fences and they just crossed backwards and forwards and it was unrecognisable as a stream.
“We took it to ECan (Environment Canterbury) and said, ‘look what’s going on here’.
“The farmer was soundly reprimanded and we began a rehabilitation planting scheme for that particular area that was completely devastated with cows and runoff and there wasn’t a plant round it – it was like a stream running through a muddy football field.”
With stock now excluded and the riparian strip planted in native trees and shrubs, the Waikakahi has been transformed from a muddy, weed infested creek into a far healthier waterway.
“Within a short time he had up to about 90 per cent of the farmers co- operating which was pretty exceptional really and probably eight to nine years after this work started, the results were quite astounding,” said Hughes. . . .
A recent study by Cawthron Institute scientist Robin Holmes confirmed the Waikakahi is returning to health. The project concentrated on structural habitat of the stream rather than water quality.
“Basically it shows that habitat in the creek has gone from what was described as a ground zero farm ditch to now it’s actually supporting a good fishery through the efforts of farmers,” Holmes said.
“It definitely goes against the current tide ongoing in the media about dairy farmers and it’s a nice example of Fish and Game and dairy farmers working together and coming up with a solution that everyone’s happy with. The creek’s gone from an A class fishery, down to a D class fishery and now it gets a C+.” . . .
But that’s just the start:
. . . Morven Glenavy Ikawai Irrigation company (MGI) chairman Robin Murphy said farmer shareholders now wanted to take the restoration to the next level and that it was important to keep monitoring the Waikakahi Stream.
“People are getting very efficient with the irrigation and also the nutrient loadings and how they put their fertiliser on. There’s a whole big effort going in there and it’s crucial to monitor that change to see what actually does happen.
“If we can save ourselves costs of putting nitrogen on or minimising nitrate loss and utilising it, that’s got to be a very good option for the farming community.” . . .
Poor farming practices degraded the waterway. A collaborative effort with farmers has improved it and will continue to do so.
There’s another good news story on cleaner water from further north.
Lake Rotoiti has reached its water quality target.
The Rotorua Lakes clean-up has made further progress with the announcement that the water quality of Lake Rotoiti is the best it’s been in decades.
The long-term programme is aimed at restoring the lakes that have suffered years of pollution from sewage discharges and nutrient run-off from farms.
Bay of Plenty Regional Council lake operations manager Andy Bruere says Lake Rotoiti has now joined the biggest of the lakes, Rotorua, in reaching the water quality target. . . .
The regional council and community groups are continuing their investigation of long-term measures to reduce nutrient flows into the Rotorua lakes.
Water wasn’t degraded overnight and there’s no quick-fix but these two examples show that a collaborative clean-up efforts are working and provide a model for areas which need to do better.