Urenui stormwater contamination health warnings still in place
29 September 2023
Public health warnings for the Urenui river and mudflats remain in place.
While remedial works have resulted in some improvement in water quality and reduced the bacterial counts in stormwater flowing into the Urenui River there is still a risk.
Dr Neil de Wet, Te Whatu Ora Medical Officer of Health for Taranaki, says that because of ongoing contamination from septic tank systems in Urenui, it is advised to:
- avoid swimming in the river after heavy rain,
- avoid collecting shellfish from the river, and
- stay off the mudflats below the township.
“There has been good progress made on remedial works since 2019, and this is reflected in reductions in bacteria counts and other indicators of human faecal contamination in stormwater samples taken from the township between 2019 and 2022,” says de Wet.
“However, the most recent sampling of stormwater continues to show elevated indicator bacteria counts, and still identifies a human faecal source. This most likely comes from septic tank systems in the Urenui township contaminating stormwater and groundwater.”
De Wet recommends not collecting shellfish from the river, as shellfish can concentrate and store any bacteria and viruses present in the water.
“As we head into the warmer summer months, there isn’t a need for a long-term warning against swimming in the river in fine weather conditions - especially at high tide which acts to dilute any bacteria in the water,” says de Wet.
“However, as with any river, we would continue emphasising the importance of avoiding swimming for 72 hours after heavy rain when the river water may become contaminated with run-off during rain events. We also recommend staying off the mudflats below the township, due to the proximity of the mudflats to the urban area.”
There will be ongoing monitoring and the Taranaki Regional Council (TRC) will be starting weekly testing of the Urenui River in November for the summer months as part of its ‘Can I Swim Here’ campaign. Results will be published on its website and at www.lawa.org.nz.
“Before swimming in the Urenui or other Taranaki rivers, lakes and beaches think about the recent weather. If there has been heavy rain in the previous few days, it’s best to stay out of the water. You can also check the LAWA site for any current warnings and for the water quality status of monitored sites.”
New Plymouth District Council (NPDC) is working on reducing wastewater from ageing septic tanks ending up in waterways around the North Taranaki towns of Urenui and Onaero. This includes connecting properties to a sewerage system and building a new wastewater treatment plant as part of its $248 million investment to fix the district’s plumbing.
It is likely that the health warnings will need to remain in place for Urenui until the reticulated wastewater system and treatment plant are constructed.
NPDC has purchased a site for the treatment plant location which is pending consents.
Last updated: Friday, September 29, 2023