Okay to swim at most popular swim spots; NRC

26 Aug 2016, 11:25 AM

The vast majority of Northland's most popular coastal swimming spots – and most of their freshwater equivalents – are suitable for swimming all or most of the time, regional council data shows.

Council Environmental Monitoring Manager Jean-Charles Perquin says hundreds of water samples were collected from 44 popular coastal and 13 freshwater summer swimming sites between late November last year and late February.

The annual water testing looks for bacteria used to gauge the risks of contracting gastrointestinal and other infections while using popular beaches, rivers and lakes for swimming, water sports and other forms of recreation.

Mr Perquin says 99.1 percent (606 out of 611) samples at coastal sites and 89.4% (161 out of 180) samples at freshwater sites over summer met national 'guideline values', meaning they were considered suitable for swimming.

A report to the last meeting of the council's Environmental Management Committee says that meant water quality was suitable for swimming "at the vast majority of coastal and most of the freshwater swimming sites, either all or most of the time".

The Kerikeri River (at the Stone Store) and the Hatea River (at Whangarei Falls) had the least suitable swimming water quality with 69% and 79% of samples within guideline values respectively.

Environmental Monitoring Officer Adam Phillips holds a sampling bottle and pole.Opua-based Environmental Monitoring Officer Adam Phillips sampling water quality at Kerikeri's Rainbow Falls. The falls were last year named among New Zealand's top 10 swimming spots.

Mr Perquin says microbial source tracking testing had been used at nine sites with consistently elevated bacterial levels, with stock and/or wild fowl markers found at four of them.

Testing identified large numbers of ducks and other water fowl fed by – and popular with – tourists and locals at the popular Kerikeri tourist spot were the main contributor to its water quality issues.

And at Whangarei Falls the regional and Whangarei District Councils were working together to address water quality issues caused by a variety of factors including contamination by birds at the falls and from stock in the Hatea River catchment.

Mr Perquin says generally where results had exceeded guideline values, many had occurred after moderate to heavy rain and had been attributed to run-off from land contaminated by faecal material, again, typically either from wild birds or stock.

He says results of each sampling run had been posted on the national environmental reporting website LAWA – www.lawa.org.nz

Weekly results had also been forwarded to the Whangarei, Far North and Kaipara District Councils, the Northland District Health Board (DHB) and other interested parties.

"The DHB and relevant district council were informed of any results showing elevated bacterial levels within 24 hours and it was then the board and/or the appropriate district council's responsibility to take action. That could include further testing, public warnings not to swim or gather shellfish and putting up permanent warning signs at the worst sites."

Mr Perquin says while far fewer people would obviously be swimming at this time of year, simple tips to judge water quality include not swimming for two or three days after heavy rain or if there are warning signs indicating unsafe water.

"You shouldn't swim if the water looks dirty or murky, smells or has scum on its surface and also look out for or consider any potential sources of contamination, both nearby and upstream."

The regional council works continuously with communities Northland-wide to try to improve water quality and its Draft Regional Plan – just-released for public feedback – also contains a numbers of measures in that regard. Key proposed changes include new stock exclusion rules for rivers, drains, wetlands and lakes.

At the same time, the council is also tailoring the way fresh water is managed in the Doubtless Bay, Pouto, Waitangi, Whangarei and Mangere catchments to address issues of particular concern to those communities.

Catchment groups made up of local community, industry and tangata whenua representatives have already developed draft catchment management plans that address fresh water related issues and contain rules that apply in addition to/instead of those in the Draft Regional Plan.

The plans also contain a variety of non-regulatory approaches (including more research and actions to improve the state of fresh water) and are also currently being consulted on.

More information (including how to have your say) about the Draft Regional Plan is available online via: www.nrc.govt.nz/newregionalplan and the catchment management plans via www.nrc.govt.nz/waiorafeedback