The water quality of Blenheim's Taylor River is the best it's been in years, but that doesn't mean it's safe to jump in just yet.
Anakiwa had some of the best water quality in Marlborough this summer. Photo: RICKY WILSON/STUFF
The Marlborough District Council has released its annual recreational water quality report, after eight beaches and eight recreational swimming spots were monitored weekly from November 2021 to the end of March 2022.
Over 80 percent of samples taken from the sites were in the low-risk category which was considered safe for swimming.
Most unsafe bacteria readings happened during or after a rain event.
However because the samples were only for that specific time and date, it needed to be combined and analysed over five summers in order to reach a "Suitability for Contact Recreation" (SFR) grade to determine whether it was safe to swim.
Beaches surveyed included Anakiwa, the Picton foreshore, Momorangi Bay, Whites Bay, Robin Hood Bay, Waikawa Bay, Governors Bay and Ngakuta Bay.
Freshwater spots included Pelorus River at the Pelorus Bridge and Totara Flat, Wairau River at the Blenheim Rowing Club and Ferry Bridge, Ohinemahuta River, Waihopai River, Rai Falls and the Taylor River.
The Taylor River, in central Blenheim, had been the site with the poorest recreational water quality in the past.
But improvements to sewage infrastructure damaged during the Kaikōura earthquake meant the water quality over the past two summers had "notably" improved.
A report presented to councillors at an environment committee meeting on Wednesday said the council had monitored two sites along the Taylor River, at Riverside, and 650 metres upstream by the Henry St bridge, sometimes used by swimmers despite warnings not to.
Samples taken from the Taylor River, in central Blenheim, show there's been a significant reduction in bacteria. Photo: RICKY WILSON/STUFF
There was only one occasion at the Taylor River where the E coli reading was considered "unsafe", which was after a rain event.
However, because E coli readings had been particularly high in the past, the SFR grade at the Taylor River was still considered "very poor", the report said.
Council environmental scientist Steffi Henkel said the majority of samples taken from swimming spots around the region this summer were "green", which meant the health risk to swimmers was generally low.
The Rai River at Rai Falls had the highest bacteria levels of the sites monitored, but when compared with data over the past 10 years, there had been a significant reduction in bacteria.
The Te Hoiere Catchment Restoration Project aimed to improve water quality at that site further.
Meanwhile Ngakuta Bay continued to have some high readings of bacteria and the compliance department at the council continued to investigate why.
Henkel said there had been one incident in mid-March where Governors Bay, about 15 minutes from Picton, had a particularly high enterococci reading.
"We did some investigation, so far it's pointing to visiting boats," she said.
"You would think it doesn't make sense if you are in the bay wanting to enjoy it."
The coastal beaches with the best recreational water quality this summer were Anakiwa and the Picton foreshore.
Blenheim ward councillor Jamie Arbuckle said he was not "overly happy" with the results from the Taylor River.
"I think we need something back sooner rather than later," he said. "I know the work is being put in, I want to know what that work is."
But Henkel said the results from the Taylor River had actually been "quite good".
"We only had one sample that was in the red. We want to make sure it stays like that," she said.
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