‘Swimmability’ has become a widely discussed freshwater issue. But for Taranaki people wanting to know where it’s suitable to swim, there’s a simple answer: www.lawa.org.nz or www.trc.govt.nz.
Taranaki freshwater monitoring results as shown on the LAWA website on 23 February. Click for big version.
Latest E. coli sampling data from popular swimming sites monitored by the Council during the recreational bathing season from November to March is shown on the Council website and on the Land Air Water Aoteaora (LAWA) website, run as a partnership between regional councils, the Cawthron Institute, MfE and Massey University.
The accompanying table shows Taranaki freshwater results as displayed on LAWA on 23 February, the day the Government announced its target of having 90% of New Zealand’s rivers ‘swimmable’ by 2040.
Both green and orange denote suitability for swimming, so 87.5% of the 16 monitored Taranaki sites are flagged as ‘swimmable’ on the day. The two ‘unacceptable’ sites are both regularly in this category and DNA testing of samples has revealed that wildfowl are the source of contamination.
“This result is fairly typical of what we see at freshwater sites over the bathing season,” says the Council’s Director-Environment Quality, Gary Bedford. “The coastal sites look even better.”
He says that while the word ‘swimmability’ rolls easily off the tongue, the concept is fraught with complications and questions. “A river in full flood and laden with debris after heavy rainfall could never be sensibly regarded as swimmable, no matter what the bacteria levels may be.”
He also says it’s important to note that E. coli are simply an indicator of a potential risk and not an actual measurement of viral contamination.“The health risk to people from swimming in our rivers changes daily and it is very simplistic to apply a pass/fail label based on historic data. People are more interested in the degree of risk at the time when they want to go swimming.”
He says the Council’s trend analyses reveal that recreational freshwater quality has been consistently improving in Taranaki over the past two decades. As noted elsewhere in this edition of Recount, the ecological health of the region’s waterways (a separate gauge from E. coli, and regarded as more reliable) has also been showing strong improvements.
Mr Bedford says the Council is studying the Government’s latest proposals and will make submissions.
“Along with local government and scientific colleagues across New Zealand, the Council has questions about the scientific basis of some of the information that was presented in support of the Government’s case,” he says. “The information is based on sampling and analyses that have not been undertaken according to long-established guidelines applying in New Zealand and similar countries.”
For Taranaki data on LAWA, go to bit.ly/TaranakiSwim(external link)
RECOUNT — Taranaki Regional Council's quarterly newsletter
Issue 104, March 2017