Invercargill City Council has been formally warned by Environment Southland after a broken outfall pipe discharged treated wastewater onto the Bluff foreshore in July.
The regional council issued the warning on 23 September, more than four months after a routine inspection first flagged the pipe as being in poor condition.
The 50-metre pipe carries treated wastewater from Bluff into Foveaux Strait at Ocean Beach. On 19 May an Environment Southland inspection found it in poor condition, and non-compliance with the council's consent was recorded.
On 16 July a magnitude 5.9 earthquake struck about 40km north of Te Anau. The following day the city council found a nine-metre section of the pipe had been damaged and reported to Environment Southland that the outfall had failed and treated wastewater was discharging onto the foreshore.
The council blames the earthquake for the failure. An earlier assessment had already found the pipe was at the end of its useful life, and relining had been scheduled for the week after the quake struck.
Normal operations were restored within a week. However, the repair used polyethylene pipe where the consent requires concrete, leaving the council out of step with its conditions.
Environment Southland says it cannot determine how much wastewater reached the foreshore because the exact time of the failure is not known.
Consent conditions still unmet
Environment Southland acting compliance manager Brad Thomas said the council "is not currently meeting all the conditions of its consent" to occupy the coastal marine area with the discharge pipe. The conditions, he said, relate to the long-term condition and appearance of the structure.
Council manager Matt Keil said the council was "continuing to work with Environment Southland on a notice to fix". Installing the consented concrete pipeline had been delayed by poor weather in recent weeks, he said.
The Bluff wastewater discharge consent itself expired in December 2025 and has continued under a status quo arrangement with the regional council. Legislation passed in August 2025 extends the existing consent to August 2028.
The formal warning records the breach. The next step is a notice to fix, which the two councils are working through, setting out what the city council must do to bring the outfall back within its consent.
The Bluff outfall had already been assessed as being at the end of its useful life before the earthquake, and the polyethylene repair that followed was an interim measure rather than the concrete replacement the consent requires.
