Investigations into summer swim spot results

12 Mar 2019, 12:04 PM

Investigations are under way into the source of consistently elevated bacterial levels at some popular Northland summer swim spots, including at Kerikeri, Whangarei Falls and Waipu’s Piroa Falls.

The Northland Regional Council’s annual summer swimming water quality monitoring programme involves tests at some of Northland’s most popular beaches, rivers and lakes. 

Council Chairman Bill Shepherd says this summer’s programme began on 03 December last year and officially ended on Monday 04 March after weekly monitoring at 46 coastal sites and 14 freshwater sites.

“We’re looking for faecal bacteria used to gauge the risks of contracting gastrointestinal and other infections while using beaches, rivers and lakes for swimming, water sports and other forms of recreation.”

Chairman Shepherd says water quality was generally suitable for swimming at ‘open coastal beaches’ most of the time, but bacterial levels were occasionally elevated at a few coastal sites – and many of Northland’s river sites – particularly after heavy rain (due to runoff of contaminants from surrounding land). 

“Some monitoring sites, such as the Stone Store, Ahuroa at Waipu’s Piroa Falls and Hatea at Whangarei Falls recorded elevated levels consistently over summer.  Previous investigations had identified wildfowl and ruminant animals (like cows) as the source/s of faecal contamination at these sites.” 

Chairman Shepherd says the regional council is currently undertaking further water quality investigations upstream of Piroa Falls and implementing land management initiatives in the upstream catchment of Whangarei Falls. 

“The full 2018/19 swimming water quality results are still to be finalised, however, weekly monitoring results for all swimming sites can be found on the LAWA website:

Chairman Shepherd says as usual over summer, weekly results were also forwarded to the Whangarei, Far North and Kaipara District Councils, the Northland District Health Board (DHB) and other interested parties. 

“We let the health board and relevant district council know of any results showing elevated bacterial levels, typically within 48 hours, as part of a jointly agreed protocol and it’s their responsibility to undertake follow-up sampling and other action.

That action can include public warnings not to swim or gather shellfish and putting up permanent warning signs at the worst sites. 

Chairman Shepherd says annual results can vary quite considerably from year to year, largely due to whether the north experiences a dry or relatively wet summer. 

The council always advises people not to swim for two or three days after heavy rain, which can carry run-off from land, or if there are warning signs indicating unsafe water. 

“As a rule of thumb, don’t swim if the water looks dirty or murky, smells or has scum on its surface and look out for or consider any potential sources of contamination, both nearby and upstream.” 

Chairman Shepherd says water quality concerns can be reported to council’s freephone 24/7 Environmental Hotline on (0800) 504 639.