Rotorua residents are being advised not to swim or play in Lake Rotorua after a wastewater leak.
A leak in a wastewater main near the Parawai Rd pump station on Tuesday night is being blamed for the incident.
It is thought around 80 cubic metres of wastewater may have entered the lake, Rotorua Lake Council said.
Following the burst, the Council initiated a temporary health warning for Lake Rotorua.
The council was alerted about the break on Tuesday and worked overnight to repair the leak, fixing it at 4.30am.
However, by the time the burst was fixed, wastewater had found its way into the lake via a stormwater drain on Parawai Rd.
A call was made to Council's after-hours service at 7.02pm last night, which was referred to on-call staff immediately.
Staff from the council, Bay of Plenty Regional Council, Trility, and Fulton Hogan responded immediately after learning of the leak.
"Contractors from Trility and Fulton Hogan worked throughout the night to repair the pipe. It was fixed at 4.30am this morning," Rotorua Lakes Council said in a statement.
"While repairs were underway, sucker trucks were used to pull wastewater away from the broken section to reduce any further flow into the lake.
"While we want to avoid any contaminant entering our waterways, in the context of the lake which contains some 800 million cubic metres of water, this was a relatively small amount."
Stakeholders and contacts were notified overnight to minimise health risks, and signage has also been placed from Waiteti to Kawaha Point.
"After further discussion with Toi Te Ora Public Health this morning, the health warning has been extended to the whole of Lake Rotorua," the statement said.
"As a precaution, the temporary health notice will be in place until further notice and regular testing of the lake water will take place during that time.
"Signage is in place around the lake to advise the public about the warning."