Most of Northland's popular swimming spots met water quality guidelines last summer

The water quality at most popular Northland swimming locations, including Whangārei Falls, met swimming guidelines last summer.

Water quality at most popular Northland swimming locations, especially those on the coast, met swimming guidelines last summer but some didn't, the common link being birds and farm animals.

So Northland Regional councillor Justin Blaikie said, after the council tested hundreds of samples at 58 sites, 16 fresh water and 42 coastal, between December 7 and March 8.

Blaikie, chairman of the council's Water and Land Working Party, said the tests, which looked for faecal bacteria, were used to gauge the risks of contracting gastrointestinal and other infections.

Ninety-eight per cent of 577 samples taken at 48 coastal sites had complied with the Ministry for the Environment's recreational bathing guidelines, with just nine failing to do so.

Subsequent microbial source tracking at six sites had revealed birds as the major source of coastal faecal contamination.

There was a bigger problem with freshwater, 28 (12 per cent) of 234 samples being non-compliant. Most of those were "one-offs", correlating with heavy rainfall 72 hours prior to sampling, but the Victoria River at Ratea, the Department of Conservation reserve on the north side of the Mangamukas, and Kawakawa's Tirohanga Stream had exceeded the guidelines numerous times.

Twenty-eight samples been taken from 12 sites for microbial source tracking.
They had "generally" identified farm stock and birds as major contributors to any contamination.

"Human sources" were reported at the Victoria River on a number of occasions, however, but could not be traced.