Tue 31 Jan 2017

The ecological health of Taranaki’s waterways continues to improve, building further on strong gains in recent years, the Taranaki Regional Council’s latest monitoring results show.

“Yet again, we’re seeing the best results ever in two decades of monitoring,” says the Council’s Director-Environment Quality, Gary Bedford. “Improvements are being seen more broadly every year. Clearly, the regional community is gaining dividends from the significant investments it’s been making in environmental protection and enhancement.”

Ecological health is the Council’s prime measure of freshwater quality and is assessed by examining what sort of tiny creatures are living in waterways. The latest report is based on analyses of samples taken in the 2015-16 year at almost 60 sites on 26 rivers and streams across the region, and on trends derived from the results of all sampling since 1995.

Findings include:

• Ecological health is improving at 46 of the 53 sites at which changes can be determined – that’s 87%, the highest percentage to date.

• Sites showing improvements outnumber those showing declines by 6.6 to one, an increase from 5.5 to one in the previous three years and 2.9 to one in 2008.

• ‘Statistically significant’ improvements are evident at 30 sites, the highest ever recorded and double the number eight years ago.

• Most of the improvements are being recorded in middle to lower catchments of the Taranaki ring plain where intensive farming occurs.

• Sites showing the most improvement are the mid reaches of the Kaupokonui Stream, the Mangaehu River at Raupuha Rd, the lower Punehu Stream, the upper and mid Kapoaiaia Stream and the lower Mangati Stream.

• The one significant negative trend is at the upper Katikara Stream, which has been affected by natural erosion events upstream in the recent past.

The technique of assessing the ecological health of waterways by looking at their populations of tiny insects other creatures is based on a scoring system called the Macroinvertebrate Community Index (MCI), which is recognised nationally and which Council scientists helped to develop in the 1980s. It is regarded as giving the best picture of the aquatic health of waterways. The Council also runs separate monitoring programmes to measure the physical and chemical state of waterways, algae levels, and summer recreational water quality at popular swimming spots.

Mr Bedford says the continuing improvements in the MCI scores are most encouraging, as they might generally be expected to flatten out after strong gains in recent years.

“Many factors are coming into play,” he says “Implementation of the Riparian Protection Scheme is in full swing, with thousands of kilometres of streambanks already fenced and protected with vegetation. Clearly, our waterways are already benefiting from this voluntary effort. And they’ll benefit even more as the scheme moves to completion at the end of the decade.”

There have also been major investments in reducing and cleaning up point-source discharges, and this is continuing with a move to land disposal of dairy effluent.

“So we can expect to see even more improvements,” says Mr Bedford.

The Council will report later on the year on the outcomes of other waterway monitoring programmes.

The latest MCI reported was presented to today's meeting of the Council's Policy and Planning Committee.

Policy and Planning Committee agenda item: bit.ly/agendaMCI

Full MCI report: bit.ly/fullMCI

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