Motueka to continue coastal rāhui
Iwi have decided to continue Motueka’s already three-month-long rāhui, banning swimming, entering the water and the collection of kaimoana, until levels of contamination are low enough.
The rāhui was put in place in October, after a failure in parts of the town’s wastewater treatment plant saw seepage of treated water into the Motueka Estuary.
The Tasman District Council said regular water testing at numerous sites around the plant showed “no significant rises in bacteria levels” following the emergency pumping programme.
However, the area will continue to be monitored and the rāhui will stay in place until “levels of contamination are considered low enough to be safe to return to activities in the area”, the council said in reponse to questions from Stuff.
The rāhui, put in place by the hau kāinga whānau of Motueka with the support of the eight mana whenua iwi of Te Tauihu and the council, covers the coastline and river mouths north of the saltwater baths to the Riuwaka river mouth and prevents the gathering of seafood and kai in those areas, as well as swimming and entering the water.
The Motueka Wastewater Treatment plant is now “on its way back to full health”, Tasman District Council communications officer Tim O’Connell said, with the faulty part – filtering membranes that the Marlborough District Council had ordered but didn’t need immediately – installed and functioning well.
Other spots off limits to swimmers in Tasman are Riuwaka, Rototai in Golden Bay, and Stephens Bay Lagoon. They were considered high risk, with a history of sewerage leaks or intensive farming in the catchment.
Stephens Bay Lagoon and Port Riuwaka, were special cases, muddy-bottomed enclosed bodies of water where faecal indicator bacteria from farming or sewerage discharges could get stored or even grow in the mud and algae sludge.
However, the general picture of good water quality at Tasman’s most popular swimming spots should not be “distorted” by a “few outliers of sites where few people swim at and which are difficult to fix quickly”, O’Connell said.
The swimming advisory at Riuwaka and Rototai, the council said, only applied to an outgoing tide and the water on an incoming tide was “very clean” unless it had rained.
Water quality was generally suitable for swimming, waterskiiing or any sport that involved putting your head under the water providing it hadn’t rained in the last 36 to 48 hours, a period in which caution was advised, the council said.
Updated information about swimming water quality can be found on the council’s website.